Publications by authors named "Julia Kenny"

26 Publications

  • Page 1 of 1

Paediatric inflammatory multisystem syndrome temporally associated with SARS-CoV-2 (PIMS-TS): the Evelina Experience.

Arch Dis Child 2020 11 10;105(11):1025-1027. Epub 2020 Sep 10.

Department of Women's and Child Health, King's College London, London, London, UK

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http://dx.doi.org/10.1136/archdischild-2020-319554DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7588407PMC
November 2020

Peripheral immunophenotypes in children with multisystem inflammatory syndrome associated with SARS-CoV-2 infection.

Nat Med 2020 11 18;26(11):1701-1707. Epub 2020 Aug 18.

Department of Intensive Care Medicine, Guy's and St Thomas' NHS Foundation Trust, London, UK.

Recent reports highlight a new clinical syndrome in children related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-multisystem inflammatory syndrome in children (MIS-C)-which comprises multiorgan dysfunction and systemic inflammation. We performed peripheral leukocyte phenotyping in 25 children with MIS-C, in the acute (n = 23; worst illness within 72 h of admission), resolution (n = 14; clinical improvement) and convalescent (n = 10; first outpatient visit) phases of the illness and used samples from seven age-matched healthy controls for comparisons. Among the MIS-C cohort, 17 (68%) children were SARS-CoV-2 seropositive, suggesting previous SARS-CoV-2 infections, and these children had more severe disease. In the acute phase of MIS-C, we observed high levels of interleukin-1β (IL-1β), IL-6, IL-8, IL-10, IL-17, interferon-γ and differential T and B cell subset lymphopenia. High CD64 expression on neutrophils and monocytes, and high HLA-DR expression on γδ and CD4CCR7 T cells in the acute phase, suggested that these immune cell populations were activated. Antigen-presenting cells had low HLA-DR and CD86 expression, potentially indicative of impaired antigen presentation. These features normalized over the resolution and convalescence phases. Overall, MIS-C presents as an immunopathogenic illness and appears distinct from Kawasaki disease.
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http://dx.doi.org/10.1038/s41591-020-1054-6DOI Listing
November 2020

Probable Vertical Transmission of SARS-CoV-2 Infection.

Pediatr Infect Dis J 2020 09;39(9):e257-e260

National Infection Service, Public Health England, London.

Background: To date, although neonatal infections with severe acute respiratory syndrome coronovirus 2 (SARS-CoV-2) have been described, none of these have been proven to be the result of vertical transmission of SARS-CoV-2.

Methods: We describe the probable vertical transmission of SARS-CoV-2 in a neonate born to a mother with coronavirus disease 2019 (COVID-19).

Results: Following cesarean section, the neonate was kept in strict isolation. Molecular tests for SARS-CoV-2 on respiratory samples, blood, and meconium were initially negative, but positive on a nasopharyngeal aspirate on the third day of life. On day 5, the neonate developed fever and coryza, which spontaneously resolved. Viral genomic analysis from the mother and neonate showed identical sequences except for 1 nucleotide.

Conclusion: This report has important implications for infection control and clinical management of pregnant women with COVID-19 and their newborns.
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http://dx.doi.org/10.1097/INF.0000000000002821DOI Listing
September 2020

Clinical Characteristics of 58 Children With a Pediatric Inflammatory Multisystem Syndrome Temporally Associated With SARS-CoV-2.

JAMA 2020 07;324(3):259-269

Section of Paediatric Infectious Disease, Department of Infectious Disease, Imperial College London, London, United Kingdom.

Importance: In communities with high rates of coronavirus disease 2019, reports have emerged of children with an unusual syndrome of fever and inflammation.

Objectives: To describe the clinical and laboratory characteristics of hospitalized children who met criteria for the pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (PIMS-TS) and compare these characteristics with other pediatric inflammatory disorders.

Design, Setting, And Participants: Case series of 58 children from 8 hospitals in England admitted between March 23 and May 16, 2020, with persistent fever and laboratory evidence of inflammation meeting published definitions for PIMS-TS. The final date of follow-up was May 22, 2020. Clinical and laboratory characteristics were abstracted by medical record review, and were compared with clinical characteristics of patients with Kawasaki disease (KD) (n = 1132), KD shock syndrome (n = 45), and toxic shock syndrome (n = 37) who had been admitted to hospitals in Europe and the US from 2002 to 2019.

Exposures: Signs and symptoms and laboratory and imaging findings of children who met definitional criteria for PIMS-TS from the UK, the US, and World Health Organization.

Main Outcomes And Measures: Clinical, laboratory, and imaging characteristics of children meeting definitional criteria for PIMS-TS, and comparison with the characteristics of other pediatric inflammatory disorders.

Results: Fifty-eight children (median age, 9 years [interquartile range {IQR}, 5.7-14]; 20 girls [34%]) were identified who met the criteria for PIMS-TS. Results from SARS-CoV-2 polymerase chain reaction tests were positive in 15 of 58 patients (26%) and SARS-CoV-2 IgG test results were positive in 40 of 46 (87%). In total, 45 of 58 patients (78%) had evidence of current or prior SARS-CoV-2 infection. All children presented with fever and nonspecific symptoms, including vomiting (26/58 [45%]), abdominal pain (31/58 [53%]), and diarrhea (30/58 [52%]). Rash was present in 30 of 58 (52%), and conjunctival injection in 26 of 58 (45%) cases. Laboratory evaluation was consistent with marked inflammation, for example, C-reactive protein (229 mg/L [IQR, 156-338], assessed in 58 of 58) and ferritin (610 μg/L [IQR, 359-1280], assessed in 53 of 58). Of the 58 children, 29 developed shock (with biochemical evidence of myocardial dysfunction) and required inotropic support and fluid resuscitation (including 23/29 [79%] who received mechanical ventilation); 13 met the American Heart Association definition of KD, and 23 had fever and inflammation without features of shock or KD. Eight patients (14%) developed coronary artery dilatation or aneurysm. Comparison of PIMS-TS with KD and with KD shock syndrome showed differences in clinical and laboratory features, including older age (median age, 9 years [IQR, 5.7-14] vs 2.7 years [IQR, 1.4-4.7] and 3.8 years [IQR, 0.2-18], respectively), and greater elevation of inflammatory markers such as C-reactive protein (median, 229 mg/L [IQR 156-338] vs 67 mg/L [IQR, 40-150 mg/L] and 193 mg/L [IQR, 83-237], respectively).

Conclusions And Relevance: In this case series of hospitalized children who met criteria for PIMS-TS, there was a wide spectrum of presenting signs and symptoms and disease severity, ranging from fever and inflammation to myocardial injury, shock, and development of coronary artery aneurysms. The comparison with patients with KD and KD shock syndrome provides insights into this syndrome, and suggests this disorder differs from other pediatric inflammatory entities.
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http://dx.doi.org/10.1001/jama.2020.10369DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7281356PMC
July 2020

A positron emission tomography imaging study to confirm target engagement in the lungs of patients with idiopathic pulmonary fibrosis following a single dose of a novel inhaled αvβ6 integrin inhibitor.

Respir Res 2020 Mar 26;21(1):75. Epub 2020 Mar 26.

GlaxoSmithKline Research and Development, Stevenage, UK.

Background: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive lung disease with poor prognosis and a significant unmet medical need. This study evaluated the safety, pharmacokinetics (PK) and target engagement in the lungs, of GSK3008348, a novel inhaled alpha-v beta-6 (αvβ6) integrin inhibitor, in participants with IPF.

Methods: This was a phase 1b, randomised, double-blind (sponsor unblind) study, conducted in the UK (two clinical sites, one imaging unit) between June 2017 and July 2018 (NCT03069989). Participants with a definite or probable diagnosis of IPF received a single nebulised dose of 1000 mcg GSK3008348 or placebo (ratio 5:2) in two dosing periods. In period 1, safety and PK assessments were performed up to 24 h post-dose; in period 2, after a 7-day to 28-day washout, participants underwent a total of three positron emission tomography (PET) scans: baseline, Day 1 (~ 30 min post-dosing) and Day 2 (~ 24 h post-dosing), using a radiolabelled αvβ6-specific ligand, [F]FB-A20FMDV2. The primary endpoint was whole lung volume of distribution (V), not corrected for air volume, at ~ 30 min post-dose compared with pre-dose. The study success criterion, determined using Bayesian analysis, was a posterior probability (true % reduction in V > 0%) of ≥80%.

Results: Eight participants with IPF were enrolled and seven completed the study. Adjusted posterior median reduction in uncorrected V at ~ 30 min after GSK3008348 inhalation was 20% (95% CrI: - 9 to 42%). The posterior probability that the true % reduction in V > 0% was 93%. GSK3008348 was well tolerated with no reports of serious adverse events or clinically significant abnormalities that were attributable to study treatment. PK was successfully characterised showing rapid absorption followed by a multiphasic elimination.

Conclusions: This study demonstrated engagement of the αvβ6 integrin target in the lung following nebulised dosing with GSK3008348 to participants with IPF. To the best of our knowledge this is the first time a target-specific PET radioligand has been used to assess target engagement in the lung, not least for an inhaled drug.

Trial Registration: clinicaltrials.gov: NCT03069989; date of registration: 3 March 2017.
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http://dx.doi.org/10.1186/s12931-020-01339-7DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7099768PMC
March 2020

In Vivo Mutagenicity Testing of Arylboronic Acids and Esters.

Environ Mol Mutagen 2019 12 17;60(9):766-777. Epub 2019 Aug 17.

Gilead Sciences, Foster City, California, 94404.

Arylboronic acids and esters (referred to collectively as arylboronic compounds) are commonly used intermediates in the synthesis of pharmaceuticals but pose a challenge for chemical syntheses because they are often positive for bacterial mutagenicity in vitro. As such, arylboronic compounds are then typically controlled to levels that are acceptable for mutagenic impurities, that is, the threshold of toxicological concern (TTC). This study used ICH M7 guidance to design and conduct a testing strategy to investigate the in vivo relevance of the in vitro positive findings of arylboronic compounds. Eight arylboronic compounds representing a variety of chemical scaffolds were tested in Sprague Dawley and/or Wistar rats in the in vivo Pig-a (peripheral blood reticulocytes and mature red blood cells) and/or comet assays (duodenum and/or liver). Five of the eight compounds were also tested in the micronucleus (peripheral blood) assay. The arylboronic compounds tested orally demonstrated high systemic exposure; thus the blood and bone marrow were adequately exposed to test article. One compound was administered intravenously due to formulation stability issues. This investigation showed that arylboronic compounds that were mutagenic in vitro were not found to be mutagenic in the corresponding in vivo assays. Therefore, arylboronic compounds similar to the scaffolds tested in this article may be considered non-mutagenic and managed in accordance with the ICH Q3A/Q3B guidelines. Environ. Mol. Mutagen. 2019. © 2019 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/em.22320DOI Listing
December 2019

Microbial Translocation Does Not Drive Immune Activation in Ugandan Children Infected With HIV.

J Infect Dis 2019 01;219(1):89-100

Infection, Immunity, and Inflammation Programme.

Objective: Immune activation is associated with morbidity and mortality during human immunodeficiency virus (HIV) infection, despite receipt of antiretroviral therapy (ART). We investigated whether microbial translocation drives immune activation in HIV-infected Ugandan children.

Methods: Nineteen markers of immune activation and inflammation were measured over 96 weeks in HIV-infected Ugandan children in the CHAPAS-3 Trial and HIV-uninfected age-matched controls. Microbial translocation was assessed using molecular techniques, including next-generation sequencing.

Results: Of 249 children included, 142 were infected with HIV; of these, 120 were ART naive, with a median age of 2.8 years (interquartile range [IQR], 1.7-4.0 years) and a median baseline CD4+ T-cell percentage of 20% (IQR, 14%-24%), and 22 were ART experienced, with a median age of 6.5 years (IQR, 5.9-9.2 years) and a median baseline CD4+ T-cell percentage of 35% (IQR, 31%-39%). The control group comprised 107 children without HIV infection. The median increase in the CD4+ T-cell percentage was 17 percentage points (IQR, 12-22 percentage points) at week 96 among ART-naive children, and the viral load was <100 copies/mL in 76% of ART-naive children and 91% of ART-experienced children. Immune activation decreased with ART use. Children could be divided on the basis of immune activation markers into the following 3 clusters: in cluster 1, the majority of children were HIV uninfected; cluster 2 comprised a mix of HIV-uninfected children and HIV-infected ART-naive or ART-experienced children; and in cluster 3, the majority were ART naive. Immune activation was low in cluster 1, decreased in cluster 3, and persisted in cluster 2. Blood microbial DNA levels were negative or very low across groups, with no difference between clusters except for Enterobacteriaceae organisms (the level was higher in cluster 1; P < .0001).

Conclusion: Immune activation decreased with ART use, with marker clustering indicating different activation patterns according to HIV and ART status. Levels of bacterial DNA in blood were low regardless of HIV status, ART status, and immune activation status. Microbial translocation did not drive immune activation in this setting.

Clinical Trials Registration: ISRCTN69078957.
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http://dx.doi.org/10.1093/infdis/jiy495DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6284549PMC
January 2019

Genotoxicity Assessment of Nanomaterials: Recommendations on Best Practices, Assays, and Methods.

Toxicol Sci 2018 08;164(2):391-416

ILSI Health and Environmental Sciences Institute (HESI), Washington, District of Columbia 20005.

Nanomaterials (NMs) present unique challenges in safety evaluation. An international working group, the Genetic Toxicology Technical Committee of the International Life Sciences Institute's Health and Environmental Sciences Institute, has addressed issues related to the genotoxicity assessment of NMs. A critical review of published data has been followed by recommendations on methods alterations and best practices for the standard genotoxicity assays: bacterial reverse mutation (Ames); in vitro mammalian assays for mutations, chromosomal aberrations, micronucleus induction, or DNA strand breaks (comet); and in vivo assays for genetic damage (micronucleus, comet and transgenic mutation assays). The analysis found a great diversity of tests and systems used for in vitro assays; many did not meet criteria for a valid test, and/or did not use validated cells and methods in the Organization for Economic Co-operation and Development Test Guidelines, and so these results could not be interpreted. In vivo assays were less common but better performed. It was not possible to develop conclusions on test system agreement, NM activity, or mechanism of action. However, the limited responses observed for most NMs were consistent with indirect genotoxic effects, rather than direct interaction of NMs with DNA. We propose a revised genotoxicity test battery for NMs that includes in vitro mammalian cell mutagenicity and clastogenicity assessments; in vivo assessments would be added only if warranted by information on specific organ exposure or sequestration of NMs. The bacterial assays are generally uninformative for NMs due to limited particle uptake and possible lack of mechanistic relevance, and are thus omitted in our recommended test battery for NM assessment. Recommendations include NM characterization in the test medium, verification of uptake into target cells, and limited assay-specific methods alterations to avoid interference with uptake or endpoint analysis. These recommendations are summarized in a Roadmap guideline for testing.
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http://dx.doi.org/10.1093/toxsci/kfy100DOI Listing
August 2018

Assessment of serum bile acid profiles as biomarkers of liver injury and liver disease in humans.

PLoS One 2018 7;13(3):e0193824. Epub 2018 Mar 7.

Drug Safety Research & Development, Pfizer Inc., Groton, Connecticut, United States of America.

To assess the potential of individual bile acids (IBA) and their profiles as mechanistic biomarkers of liver injury for humans in real world situations, we interrogated samples collected under minimum controlled conditions (ie subjects were not fasted). Total bile acids (TBA) have been considered to be biomarkers of liver injury for decades, and more recently, monitoring of IBA has been proposed for differentiation of variety of etiologies of liver injury. We established a LC-MS/MS methodology to analyze nine IBA, generated reference ranges, and examined effects of age, gender, and ethnicity for each IBA. Furthermore, we evaluated the ability of IBA and their profiles to detect hepatic injury in subjects with a broad range of liver impairments. To date, our study utilized the largest total cohort of samples (N = 645) that were divided into 2 groups, healthy or liver impaired, to evaluate IBA as biomarkers. The TBA serum levels in the Asian ethnic group trended higher when compared to other ethnic groups, and the serum concentrations of IBA, such as glycocholic acid (GCA), glycochenodeoxycholic acid (GCDCA), chenodeoxycholic acid (CDCA), and taurochenoxycholic acid (TCDCA) were significantly increased. To our knowledge, this report is the first to describe ethnic differences in serum concentrations of IBAs. In patients with hepatic impairments, with the exception of deoxycholic acid (DCA), the concentrations of IBAs were significantly elevated when compared with healthy subjects. The conjugated bile acids displayed greater differences between healthy subjects and subjects with hepatic impairments than non-conjugated bile acids. Furthermore, the subjects with hepatic impairments exhibited distinct profiles (signatures) of IBAs that clustered subjects according the nature of their liver impairments. Although additional studies are needed, our data suggested that the analysis of IBA has the potential to become useful for differentiation of various forms of liver injury.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0193824PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5841799PMC
June 2018

A Microdose PET Study of the Safety, Immunogenicity, Biodistribution, and Radiation Dosimetry of F-FB-A20FMDV2 for Imaging the Integrin αβ.

J Nucl Med Technol 2018 Jun 2;46(2):136-143. Epub 2018 Feb 2.

Fibrosis Discovery Performance Unit, GlaxoSmithKline R&D, Stevenage, United Kingdom; and

The αβ integrin is involved in the pathogenesis of cancer and fibrosis. A radiolabeled 20-amino-acid αβ-binding peptide, derived from the foot and mouth virus (NAVPNLRGDLQVLAQKVART [A20FMDV2]), has been developed to image αβ levels preclinically. This study was designed to translate these findings into a clinical PET imaging protocol to measure the expression of αβ in humans. Preclinical toxicology was undertaken, and a direct immunoassay was developed for 4-fluorobenzamide (FB)-A20FMDV2. Four healthy human subjects (2 male and 2 female) received a single microdose of F-FB-A20FMDV2 followed by a multibed PET scan of the whole body over more than 3 h. There were no findings in the preclinical toxicology assessments, and no anti-A20FMDV2 antibodies were detected before or after dosing with the PET ligand. The mean and SD of the administered mass of F-FB-A20FMDV2 was 8.7 ± 4.4 μg (range, 2.7-13.0 μg). The mean administered activity was 124 ± 20 MBq (range, 98-145 MBq). There were no adverse or clinically detectable pharmacologic effects in any of the subjects. No significant changes in vital signs, laboratory study results, or electrocardiography results were observed. Uptake of radioactivity was observed in the thyroid, salivary glands, liver, stomach wall, spleen, kidneys, ureters, and bladder. Time-activity curves indicated that the highest activity was in the bladder content, followed by the kidneys, small intestine, stomach, liver, spleen, thyroid, and gallbladder. The largest component of the residence times was the voided urine, followed by muscle, bladder, and liver. Using the mean residence time over all subjects as input to OLINDA/EXM, the effective dose was determined to be 0.0217 mSv/MBq; using residence times from single subjects gave an SD of 0.0020 mSv/MBq from the mean. The critical organ was the urinary bladder, with an absorbed dose of 0.18 mGy/MBq. F-FB-A20FMDV2 successfully passed toxicology criteria, showed no adverse effects in this first-in-humans study, and has an effective dose that enables multiple scans in a single subject.
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http://dx.doi.org/10.2967/jnmt.117.203547DOI Listing
June 2018

Presentation of life-threatening invasive nontyphoidal Salmonella disease in Malawian children: A prospective observational study.

PLoS Negl Trop Dis 2017 12 7;11(12):e0006027. Epub 2017 Dec 7.

Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, University of Malawi, Malawi.

Nontyphoidal Salmonellae commonly cause invasive disease in African children that is often fatal. The clinical diagnosis of these infections is hampered by the absence of a clear clinical syndrome. Drug resistance means that empirical antibiotic therapy is often ineffective and currently no vaccine is available. The study objective was to identify risk factors for mortality among children presenting to hospital with invasive Salmonella disease in Africa. We conducted a prospective study enrolling consecutive children with microbiologically-confirmed invasive Salmonella disease admitted to Queen Elizabeth Central Hospital, Blantyre, in 2006. Data on clinical presentation, co-morbidities and outcome were used to identify children at risk of inpatient mortality through logistic-regression modeling. Over one calendar year, 263 consecutive children presented with invasive Salmonella disease. Median age was 16 months (range 0-15 years) and 52/256 children (20%; 95%CI 15-25%) died. Nontyphoidal serovars caused 248/263 (94%) of cases. 211/259 (81%) of isolates were multi-drug resistant. 251/263 children presented with bacteremia, 6 with meningitis and 6 with both. Respiratory symptoms were present in 184/240 (77%; 95%CI 71-82%), 123/240 (51%; 95%CI 45-58%) had gastrointestinal symptoms and 101/240 (42%; 95%CI 36-49%) had an overlapping clinical syndrome. Presentation at <7 months (OR 10.0; 95%CI 2.8-35.1), dyspnea (OR 4.2; 95%CI 1.5-12.0) and HIV infection (OR 3.3; 95%CI 1.1-10.2) were independent risk factors for inpatient mortality. Invasive Salmonella disease in Malawi is characterized by high mortality and prevalence of multi-drug resistant isolates, along with non-specific presentation. Young infants, children with dyspnea and HIV-infected children bear a disproportionate burden of the Salmonella-associated mortality in Malawi. Strategies to improve prevention, diagnosis and management of invasive Salmonella disease should be targeted at these children.
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http://dx.doi.org/10.1371/journal.pntd.0006027DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5745124PMC
December 2017

Insulin Resistance and Markers of Inflammation in HIV-infected Ugandan Children in the CHAPAS-3 Trial.

Pediatr Infect Dis J 2017 08;36(8):761-767

From the *Case Western Reserve University, and†Rainbow Babies and Children's Hospital, Cleveland, Ohio; ‡Joint Clinical Research Centre, and §Makerere University College of Health Sciences, Kampala, Uganda; ¶MRC Clinical Trials Unit University College, and ‖Institute of Child Health University College, London, United Kingdom.

Background: Few studies have investigated metabolic complications in HIV-infected African children and their relation with inflammation.

Methods: We compared baseline and changes in insulin resistance [homeostatic model assessment of insulin resistance (HOMA-IR)] and in markers of inflammation over 48 weeks, in a subset of antiretroviral therapy (ART)-naive Ugandan children from the Children with HIV in Africa-Pharmacokinetics and Adherence/Acceptability of Simple Antiretroviral Regimens trial randomized to zidovudine-, stavudine- or abacavir (ABC)-based regimen. Nonparametric methods were used to explore between-group and within-group differences, and multivariable analysis to assess associations of HOMA-IR.

Results: One-hundred eighteen children were enrolled, and median age (interquartile range) was 2.8 years (1.7-4.3). Baseline median HOMA-IR (interquartile range) was 0.49 (0.38-1.07) and similar between the arms. At week 48, median relative changes in HOMA-IR were 14% (-29% to 97%) in the zidovudine arm, -1% (-30% to 69%) in the stavudine arm and 6% (-34% to 124%) in the ABC arm (P ≤ 0.03 for all the arms compared with baseline, but P = 0.90 for between-group differences). Several inflammation markers significantly decreased in all study arms; soluble CD14 increased on ABC and did not change in the other 2 arms. In multivariate analysis, only changes in soluble CD163 were positively associated with HOMA-IR changes.

Conclusions: In ART-naive Ugandan children, HOMA-IR changed significantly after 48 weeks of ART and correlated with monocyte activation.
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http://dx.doi.org/10.1097/INF.0000000000001544DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6563907PMC
August 2017

Who Gets Severe Gynecomastia Among HIV-infected Children in the United Kingdom and Ireland?

Pediatr Infect Dis J 2017 03;36(3):307-310

From the *MRC Clinical Trials Unit at UCL, University College London, London, United Kingdom; and †St. George's Healthcare NHS Trust, London, United Kingdom.

There are few data on gynecomastia in HIV-infected children. Within the UK/Ireland's national cohort, 56 of 1873 (3%) HIV-infected children had gynecomastia, of which 10 (0.5%) were severe. All 10 had received antiretroviral therapy for a median of 27.5 (21, 42) months; 4 of 10 had received efavirenz, 7 of 10 and 6 of 10 had received stavudine and/or didanosine respectively. Five were nonreversible, despite changing antiretroviral therapy, and required breast reduction surgery.
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http://dx.doi.org/10.1097/INF.0000000000001424DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5929399PMC
March 2017

In Vivo Pig-a gene mutation assay: Guidance for 3Rs-friendly implementation.

Environ Mol Mutagen 2016 12 22;57(9):678-686. Epub 2016 Oct 22.

Bayer Pharma AG, Muellerstrasse 178, Berlin, 13353, Germany.

The rodent Pig-a assay is an in vivo method for the detection of gene mutation, where lack of glycosylphosphatidylinositol-anchored proteins on the surface of circulating red blood cells (RBCs) serves as a reporter for Pig-a gene mutation. In the case of rats, the frequency of mutant phenotype RBCs is measured via fluorescent anti-CD59 antibodies and flow cytometry. The Pig-a assay meets the growing expectations for novel approaches in animal experimentation not only focusing on the scientific value of the assay but also on animal welfare aspects (3Rs principles), for example, amenable to integration into pivotal rodent 28-day general toxicology studies. However, as recommended in the Organisation for Economic Co-operation and Development Test Guidelines for genotoxicity testing, laboratories are expected to demonstrate their proficiency. While this has historically involved the extensive use of animals, here we describe an alternative approach based on a series of blood dilutions covering a range of mutant frequencies. The experiments described herein utilized either non-fluorescent anti-CD59 antibodies to provide elevated numbers of mutant-like cells, or a low volume blood sample from a single N-ethyl-N-nitrosourea treated animal. Results from these so-called reconstruction experiments from four independent laboratories showed good overall precision (correlation coefficients: 0.9979-0.9999) and accuracy (estimated slope: 0.71-1.09) of mutant cell scoring, which was further confirmed by Bland-Altman analysis. These data strongly support the use of reconstruction experiments for training purposes and demonstrating laboratory proficiency with very few animals, an ideal situation given the typically conflicting goals of demonstrating laboratory proficiency and reducing the use of animals. Environ. Mol. Mutagen. 57:678-686, 2016. © 2016 Wiley Periodicals, Inc.
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http://dx.doi.org/10.1002/em.22060DOI Listing
December 2016

BREATHER (PENTA 16) short-cycle therapy (SCT) (5 days on/2 days off) in young people with chronic human immunodeficiency virus infection: an open, randomised, parallel-group Phase II/III trial.

Health Technol Assess 2016 06;20(49):1-108

Medical Research Council Clinical Trials Unit at University College London (MRC CTU at UCL), London, UK.

Background: For human immunodeficiency virus (HIV)-infected adolescents facing lifelong antiretroviral therapy (ART), short-cycle therapy (SCT) with long-acting agents offers the potential for drug-free weekends, less toxicity, better adherence and cost savings.

Objectives: To determine whether or not efavirenz (EFV)-based ART in short cycles of 5 days on and 2 days off is as efficacious (in maintaining virological suppression) as continuous EFV-based ART (continuous therapy; CT). Secondary objectives included the occurrence of new clinical HIV events or death, changes in immunological status, emergence of HIV drug resistance, drug toxicity and changes in therapy.

Design: Open, randomised, non-inferiority trial.

Setting: Europe, Thailand, Uganda, Argentina and the USA.

Participants: Young people (aged 8-24 years) on EFV plus two nucleoside reverse transcriptase inhibitors and with a HIV-1 ribonucleic acid level [viral load (VL)] of < 50 copies/ml for > 12 months.

Interventions: Young people were randomised to continue daily ART (CT) or change to SCT (5 days on, 2 days off ART).

Main Outcome Measures: Follow-up was for a minimum of 48 weeks (0, 4 and 12 weeks and then 12-weekly visits). The primary outcome was the difference between arms in the proportion with VL > 50 copies/ml (confirmed) by 48 weeks, estimated using the Kaplan-Meier method (12% non-inferiority margin) adjusted for region and age.

Results: In total, 199 young people (11 countries) were randomised (n = 99 SCT group, n = 100 CT group) and followed for a median of 86 weeks. Overall, 53% were male; the median age was 14 years (21% ≥ 18 years); 13% were from the UK, 56% were black, 19% were Asian and 21% were Caucasian; and the median CD4% and CD4 count were 34% and 735 cells/mm(3), respectively. By week 48, only one participant (CT) was lost to follow-up. The SCT arm had a 27% decreased drug exposure as measured by the adherence questionnaire and a MEMSCap(™) Medication Event Monitoring System (MEMSCap Inc., Durham, NC, USA) substudy (median cap openings per week: SCT group, n = 5; CT group, n = 7). By 48 weeks, six participants in the SCT group and seven in the CT group had a confirmed VL > 50 copies/ml [difference -1.2%, 90% confidence interval (CI) -7.3% to 4.9%] and two in the SCT group and four in the CT group had a confirmed VL > 400 copies/ml (difference -2.1%, 90% CI -6.2% to 1.9%). All six participants in the SCT group with a VL > 50 copies/ml resumed daily ART, of whom five were resuppressed, three were on the same regimen and two with a switch; two others on SCT resumed daily ART for other reasons. Overall, three participants in the SCT group and nine in the CT group (p = 0.1) changed ART regimen, five because of toxicity, four for simplification reasons, two because of compliance issues and one because of VL failure. Seven young people (SCT group, n = 2; CT group, n = 5) had major non-nucleoside reverse transcriptase inhibitor mutations at VL failure, of whom two (n = 1 SCT group, n = 1 CT group) had the M184V mutation. Two young people had new Centers for Disease Control B events (SCT group, n = 1; CT group, n = 1). There were no significant differences between SCT and CT in grade 3/4 adverse events (13 vs. 14) or in serious adverse events (7 vs. 6); there were fewer ART-related adverse events in the SCT arm (2 vs. 14; p = 0.02). At week 48 there was no evidence that SCT led to increased inflammation using an extensive panel of markers. Young people expressed a strong preference for SCT in a qualitative substudy and in pre- and post-trial questionnaires. In total, 98% of the young people are taking part in a 2-year follow-up extension of the trial.

Conclusions: Non-inferiority of VL suppression in young people on EFV-based first-line ART with a VL of < 50 copies/ml was demonstrated for SCT compared with CT, with similar resistance, safety and inflammatory marker profiles. The SCT group had fewer ART-related adverse events. Further evaluation of the immunological and virological impact of SCT is ongoing. A limitation of the trial is that the results cannot be generalised to settings where VL monitoring is either not available or infrequent, nor to use of low-dose EFV. Two-year extended follow-up of the trial is ongoing to confirm the durability of the SCT strategy. Further trials of SCT in settings with infrequent VL monitoring and with other antiretroviral drugs such as tenofovir alafenamide, which has a long intracellular half-life, and/or dolutegravir, which has a higher barrier to resistance, are planned.

Trial Registration: Current Controlled Trials ISRCTN97755073; EUDRACT 2009-012947-40; and CTA 27505/0005/001-0001.

Funding: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme (projects 08/53/25 and 11/136/108), the European Commission through EuroCoord (FP7/2007/2015), the Economic and Social Research Council, the PENTA Foundation, the Medical Research Council and INSERM SC10-US19, France, and will be published in full in Health Technology Assessment; Vol. 20, No. 49. See the NIHR Journals Library website for further project information.
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http://dx.doi.org/10.3310/hta20490DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4947878PMC
June 2016

Abacavir, zidovudine, or stavudine as paediatric tablets for African HIV-infected children (CHAPAS-3): an open-label, parallel-group, randomised controlled trial.

Lancet Infect Dis 2016 Feb 5;16(2):169-79. Epub 2015 Oct 5.

Medical Research Council Clinical Trials Unit at University College London, London, UK. Electronic address:

Background: WHO 2013 guidelines recommend universal treatment for HIV-infected children younger than 5 years. No paediatric trials have compared nucleoside reverse-transcriptase inhibitors (NRTIs) in first-line antiretroviral therapy (ART) in Africa, where most HIV-infected children live. We aimed to compare stavudine, zidovudine, or abacavir as dual or triple fixed-dose-combination paediatric tablets with lamivudine and nevirapine or efavirenz.

Methods: In this open-label, parallel-group, randomised trial (CHAPAS-3), we enrolled children from one centre in Zambia and three in Uganda who were previously untreated (ART naive) or on stavudine for more than 2 years with viral load less than 50 copies per mL (ART experienced). Computer-generated randomisation tables were incorporated securely within the database. The primary endpoint was grade 2-4 clinical or grade 3/4 laboratory adverse events. Analysis was intention to treat. This trial is registered with the ISRCTN Registry number, 69078957.

Findings: Between Nov 8, 2010, and Dec 28, 2011, 480 children were randomised: 156 to stavudine, 159 to zidovudine, and 165 to abacavir. After two were excluded due to randomisation error, 156 children were analysed in the stavudine group, 158 in the zidovudine group, and 164 in the abacavir group, and followed for median 2·3 years (5% lost to follow-up). 365 (76%) were ART naive (median age 2·6 years vs 6·2 years in ART experienced). 917 grade 2-4 clinical or grade 3/4 laboratory adverse events (835 clinical [634 grade 2]; 40 laboratory) occurred in 104 (67%) children on stavudine, 103 (65%) on zidovudine, and 105 (64%), on abacavir (p=0·63; zidovudine vs stavudine: hazard ratio [HR] 0·99 [95% CI 0·75-1·29]; abacavir vs stavudine: HR 0·88 [0·67-1·15]). At 48 weeks, 98 (85%), 81 (80%) and 95 (81%) ART-naive children in the stavudine, zidovudine, and abacavir groups, respectively, had viral load less than 400 copies per mL (p=0·58); most ART-experienced children maintained suppression (p=1·00).

Interpretation: All NRTIs had low toxicity and good clinical, immunological, and virological responses. Clinical and subclinical lipodystrophy was not noted in those younger than 5 years and anaemia was no more frequent with zidovudine than with the other drugs. Absence of hypersensitivity reactions, superior resistance profile and once-daily dosing favours abacavir for African children, supporting WHO 2013 guidelines.

Funding: European Developing Countries Clinical Trials Partnership.
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http://dx.doi.org/10.1016/S1473-3099(15)00319-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4726762PMC
February 2016

Anthropometric measurements and lipid profiles to detect early lipodystrophy in antiretroviral therapy experienced HIV-infected children in the CHAPAS-3 trial.

Antivir Ther 2014 25;19(3):269-76. Epub 2013 Oct 25.

Joint Clinical Research Centre, Kampala, Uganda.

Background: Few studies have investigated objective markers of lipodystrophy in African children. We compared body circumferences, skin-fold thickness (SFT) and lipids in antiretroviral therapy (ART)-naive and stavudine (d4T)-exposed children with HIV-uninfected controls.

Methods: In the CHAPAS-3 trial, HIV-infected children (ART-naive or on d4T for ≥2 years without clinical lipodystrophy) were randomized to d4T, abacavir or zidovudine with lamivudine (3TC) plus a non-nucleoside reverse transcriptase inhibitor. Mid-upper-arm circumference (MUAC) and calf circumference (CC), SFT (biceps, triceps, sub-scapular and supra-iliac) and fasting lipids (total cholesterol [TC], low-density lipoprotein [LDL], high-density lipoprotein [HDL] and triglycerides [TRIG]) were measured at randomization in all HIV-infected children, and in HIV-uninfected controls. Age- and sex-adjusted z-scores of MUAC, CC, SFT and the sum of SFT (SSF) using Dutch reference data were compared across groups using linear regression.

Results: Of 496 children, 49% were male, 299 (median age 2.5 years [IQR 1.5-4.0]) were ART-naive, 109 (median age 6 years [IQR 5.5-7.0]) were ART-experienced and 88 (median age 2.2 years [IQR 1.5-3.0]) were control children. Overall, 100% and 95% of ART-experienced children had been on d4T plus 3TC and nevirapine, respectively, for a median 3.5 years (IQR 2.6-4.2). Mean (sd) weight-for-age z-scores and MUAC z-scores were -1.51 (1.29) versus -0.90 (0.88) versus -0.33 (1.15) and -1.56 (1.25) versus -1.24 (0.97) versus -0.65 (1.06) in ART-naive versus -experienced versus controls, respectively (all P<0.02). The mean (sd) of SSF was lower in the ART-experienced (-0.78 [1.28]) than in the ART-naive (-0.32 [1.09]; P<0.0001) children and controls (-0.29 [0.88]; P<0.002). ART-experienced children had higher mean fasting TC, LDL and HDL but lower TRIG compared to ART-naive children (P-values <0.0001), and higher TC and HDL but lower TRIG compared to controls (P-values <0.01).

Conclusions: In ART-experienced children on d4T-containing regimens, we observed lower SFT and higher TC and LDL values compared to ART-naive children and HIV-uninfected controls.
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http://dx.doi.org/10.3851/IMP2695DOI Listing
January 2015

Use of human in vitro skin models for accurate and ethical risk assessment: metabolic considerations.

Toxicol Sci 2013 Jun 28;133(2):209-17. Epub 2013 Mar 28.

SWS, 64390 Erzhausen, Germany.

Several human skin models employing primary cells and immortalized cell lines used as monocultures or combined to produce reconstituted 3D skin constructs have been developed. Furthermore, these models have been included in European genotoxicity and sensitization/irritation assay validation projects. In order to help interpret data, Cosmetics Europe (formerly COLIPA) facilitated research projects that measured a variety of defined phase I and II enzyme activities and created a complete proteomic profile of xenobiotic metabolizing enzymes (XMEs) in native human skin and compared them with data obtained from a number of in vitro models of human skin. Here, we have summarized our findings on the current knowledge of the metabolic capacity of native human skin and in vitro models and made an overall assessment of the metabolic capacity from gene expression, proteomic expression, and substrate metabolism data. The known low expression and function of phase I enzymes in native whole skin were reflected in the in vitro models. Some XMEs in whole skin were not detected in in vitro models and vice versa, and some major hepatic XMEs such as cytochrome P450-monooxygenases were absent or measured only at very low levels in the skin. Conversely, despite varying mRNA and protein levels of phase II enzymes, functional activity of glutathione S-transferases, N-acetyltransferase 1, and UDP-glucuronosyltransferases were all readily measurable in whole skin and in vitro skin models at activity levels similar to those measured in the liver. These projects have enabled a better understanding of the contribution of XMEs to toxicity endpoints.
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http://dx.doi.org/10.1093/toxsci/kft080DOI Listing
June 2013

The needs for HIV treatment and care of children, adolescents, pregnant women and older people in low-income and middle-income countries.

AIDS 2012 Dec;26 Suppl 2:S105-16

Clinical Trials Unit, Medical Research Council, and Department of Infectious Diseases and Microbiology, Institute of Child Health, University College London, 30 Guilford St., London, UK.

Objective: Success in diagnosing and treating HIV-infected adults has, where HIV care and treatment is available, turned HIV into a chronic, rather than life-limiting disease. Progress meeting the needs of HIV-infected children, perinatally and horizontally infected adolescents, pregnant women and older people has lagged behind. We review the special needs and barriers to scaling up care and antiretroviral therapy (ART) coverage in these populations.

Design And Methods: A literature review combined with personal views and operational experience specifically from countries covered by the Evidence for Action programme.

Results: Challenges include logistics of diagnosis and treatment in pregnancy, difficulties in early infant diagnosis, availability of appropriate paediatric formulations, management of adolescents, and comorbidities in older people.

Conclusion: Priorities for development need to focus upon the simplification of HIV care to allow provision for all ages at the primary healthcare level. Specific priorities include focused use of virological testing in infants, ongoing development of dispersible and scored fixed-dose ART combinations suitable for use across ages, development of 'adolescent-friendly' HIV services catering for perinatally and horizontally infected adolescents to improve adherence and reduce onward transmissions, simplification of referral pathways to ensure all pregnant women are tested for HIV and commenced on ART, and education of healthcare workers on the specific needs of HIV care in older patients. Each priority will be reviewed and potential solutions discussed.
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http://dx.doi.org/10.1097/QAD.0b013e32835bddfcDOI Listing
December 2012

The in vivo rat skin photomicronucleus assay: phototoxicity and photogenotoxicity evaluation of six fluoroquinolones.

Mutagenesis 2012 Nov 30;27(6):721-9. Epub 2012 Aug 30.

TNO Triskelion, Utrechtseweg 48, 3704 HE Zeist, The Netherlands.

An in vivo photomicronucleus test (MNT) using rat skin, the target organ for photoirritancy and carcinogenicity, was recently described. The assay was evaluated using fluoroquinolone (FQ) antibiotics with varying degrees of phototoxic potency (i.e. sparflocacin [SPFX], lomefloxacin [LOFX], ciprofloxacin [CIFX], levofloxacin [LEFX], gemifloxacin [GEFX] and gatifloxacin [GAFX]) using a solar simulator producing both UVA and UVB (ratio 23:1). Experiments were performed at The Netherlands Organisation for Applied Scientific Research (TNO) and GlaxoSmithKline (GSK) to investigate interlaboratory variability, including evaluation of phototoxicity (clinical signs), micronucleus induction and histopathology. The potency of micronuclei (MN) formation in rat skin induced by the FQs was SPFX = LOFX > CIFX = LEFX, however, MN induction was only statistically significant for SPFX and LOFX. In both laboratories, GEFX and GAFX did not increase the MN frequencies compared to the irradiated vehicle control. Signs of phototoxicity, including clinical and histopathological changes, were observed with SPFX and LOFX to a similar degree as the positive control, 8-methoxypsoralen. In addition, there were some clinical signs of phototoxicity seen with CIFX, LEFX, GEFX and GAFX, but not always in both laboratories for CIFX, GEFX and GAFX and when observed, these were considered only mild. Of these, only LEFX also showed histopathological changes. In all studies, photogenotoxic potency correlated with photocarcinogenic potential and moreover, photogenotoxicity was not observed in the absence of phototoxicity. The results of the TNO/GSK study indicate that the in vivo rat skin photoMNT may be a promising tool for detection of photoclastogencity and photoirritancy in the skin/eye in the same animal. Given the association between the MNT and cancer, the skin photoMNT may also provide a promising tool for the early detection of photocarcinogenesis and help bridge the gap in the existing photosafety testing paradigm.
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http://dx.doi.org/10.1093/mutage/ges038DOI Listing
November 2012

Recent advances in pharmacovigilance of antiretroviral therapy in HIV-infected and exposed children.

Curr Opin HIV AIDS 2012 Jul;7(4):305-16

Medical Research Council, Clinical Trials Unit, London, UK.

Purpose Of Review: Antiretroviral therapy (ART) has greatly improved the survival of HIV-infected children. However, ART is associated with immediate and long-term adverse events. Pharmacovigilance systems, although imperfect, have been developed in many high-income countries (HICs), but coverage in low- and middle-income countries (LMICs) is poor and uneven. This review covers the recent advances in the understanding of adverse events following perinatal ART exposure, including surveillance from birth cohorts; we also describe the adverse events of antiretroviral drugs among HIV-infected children, focussing particularly on those relevant to LMICs, where more than 90% of HIV-infected children live.

Recent Findings: ART is largely safe in both HIV-infected and HIV-exposed uninfected children, in whom no significant increase in birth defects has been noted. Among HIV-infected children, toxicity to some drugs may be less frequent than in adults, possibly related to immature immune systems in younger children. As per WHO guidelines, many countries are moving from stavudine-based to zidovudine-based or abacavir-based fixed-dose combination (with nevirapine/lamivudine) paediatric mini-pills. However, reassuring data are emerging about short-term stavudine use in LMICs, as this remains an important first-line regimen for young children, as well as an alternative to zidovudine for anaemic children. Zidovudine appears to be well tolerated in young children living in nonmalarious areas, and, among African children, concerns about abacavir hypersensitivity have not been substantiated.

Summary: Optimization of first-line ART regimens needs to take account of the toxicities in HIV-infected children, in particular as they will take ART much longer than adults and during the period of growth and development. The benefits of ART in pregnancy are clear, but long-term follow-up of ART-exposed infants in LMICs through integrated surveillance systems would be invaluable.
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http://dx.doi.org/10.1097/COH.0b013e328354da1dDOI Listing
July 2012

International Pig-a gene mutation assay trial (stage III): results with N-methyl-N-nitrosourea.

Environ Mol Mutagen 2011 Dec;52(9):699-710

GlaxoSmithKline, Ware, Hertfordshire, United Kingdom.

N-methyl-N-nitrosourea (MNU) was evaluated in the in vivo Pig-a mutation assay as part of an International Collaborative Trial to investigate laboratory reproducibility, 28-day study integration, and comparative analysis with micronucleus (MN), comet, and clinical pathology endpoints. Male Sprague Dawley rats were treated for 28 days with doses of 0, 2.5, 5, and 10 mg MNU/kg/day in two independent laboratories, GlaxoSmithKline (GSK) and Bristol Myers Squibb (BMS). Additional studies investigated the low-dose region (<2.5 mg/kg/day). Reticulocytes were evaluated for Pig-a phenotypic mutation, CD59-negative reticulocytes/erythrocytes (RETs(CD592-)/ RBCs(CD592-)) on Days 1, 4, 15, 29, 43, and 57, and for micronucleated reticulocytes (MN-RETs) on Days 4 and 29. Comet analysis was conducted for liver and whole blood, and hematology and clinical chemistry was investigated. Dose-dependent increases in the frequency of RETs(CD592-) and RBCs(CD592-) were observed by Day 15 or 29, respectively. Dose-dependent increases were observed in %MN-RET on Days 4 and 29, and in mean %tail intensity in liver and in blood. Hematology/clinical chemistry data demonstrated bone marrow toxicity. Data comparison between GSK and BMS indicated a high degree of concordance with the Pig-a mutation assay results, consistent with previous observations with MNU and N-ethyl-N-nitrosourea. These data confirm that complementary genotoxicity endpoints can be effectively incorporated into routine toxicology studies, a strategy that can provide information on gene mutation, chromosome damage, and DNA strand breaks in a single repeat dose rodent study. Collectively, this would reduce animal usage while providing valuable genetic toxicity information within the context of other toxicological endpoints.
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http://dx.doi.org/10.1002/em.20691DOI Listing
December 2011

International Pig-a gene mutation assay trial: evaluation of transferability across 14 laboratories.

Environ Mol Mutagen 2011 Dec 11;52(9):690-8. Epub 2011 Sep 11.

Litron Laboratories, Rochester, New York, USA.

A collaborative international trial was conducted to evaluate the reproducibility and transferability of an in vivo mutation assay based on the enumeration of CD59-negative rat erythrocytes, a phenotype that is indicative of Pig-a gene mutation. Fourteen laboratories participated in this study, where anti-CD59-PE, SYTO 13 dye, and flow cytometry were used to determine the frequency of CD59-negative erythrocytes (RBC(CD59-)) and CD59-negative reticulocytes (RET(CD59-)). To provide samples with a range of mutant phenotype cell frequencies, male rats were exposed to N-ethyl-N-nitrosourea (ENU) via oral gavage for three consecutive days (Days 1-3). Each laboratory studied 0, 20, and 40 mg ENU/kg/day (n = 5 per group). Three sites also evaluated 4 mg/kg/day. At a minimum, blood samples were collected three times: predosing and on Days 15 and 30. Blood samples were processed according to a standardized sample processing and data acquisition protocol, and three endpoints were measured: %reticulocytes, frequency of RET(CD59-) , and frequency of RBC(CD59-) . The methodology was found to be reproducible, as the analysis of technical replicates resulted in experimental coefficients of variation that approached theoretical values. Good transferability was evident from the similar kinetics and magnitude of the dose-related responses that were observed among different laboratories. Concordance correlation coefficients showed a high level of agreement between the reference site and the test sites (range: 0.87-0.99). Collectively, these data demonstrate that with adequate training of personnel, flow cytometric analysis is capable of reliably enumerating mutant phenotype erythrocytes, thereby providing a robust in vivo mutation assay that is readily transferable across laboratories.
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http://dx.doi.org/10.1002/em.20672DOI Listing
December 2011

Development and characterization of an in vivo skin photomicronucleus assay in rats.

Mutagenesis 2010 Jul 11;25(4):407-16. Epub 2010 May 11.

TNO Quality of Life, Zeist, The Netherlands.

For pharmaceuticals, current regulatory guidance for photosafety testing states that studies are warranted for drug candidates that both absorb light in the range of 290-700 nm and that are either applied topically or reach the skin or eyes by systemic exposure. In contrast to standard genotoxicity evaluations, where a positive (or equivocal) result in vitro can be placed into context with additional testing in vivo, there are no equivalent short-term in vivo photogenotoxicity assays in the current photosafety test battery. Therefore, a short-term in vivo assay for the evaluation of a photogenotoxic potential in the skin, the target organ for photocarcinogenicity, was developed in rats. After oral 8-methoxypsoralen administration, rats were exposed to ultraviolet radiation and sacrificed 3 days after treatment to isolate epidermal cells for subsequent micronucleus (MN) evaluation. Optimal conditions were determined to obtain maximal induction of MN, followed by demonstrating feasibility and reproducibility of the method. The results of the present study indicate that the in vivo rat skin photomicronucleus test may be a promising tool for detection of photoclastogenicity. Given the association between MN induction and cancer, the assay may also provide a promising tool for the early detection of photocarcinogenesis and help bridge the gap in the existing photosafety testing paradigm.
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http://dx.doi.org/10.1093/mutage/geq023DOI Listing
July 2010

Comparison of previous and present World Health Organization clinical staging criteria in HIV-infected Malawian children.

AIDS 2009 Sep;23(14):1913-6

Department of Paediatrics, Queen Elizabeth Central Hospital, Blantyre, Malawi.

In many settings, HIV infected children are looked after with limited access to CD4 cell count or viral load. The decision to initiate antiretroviral therapy (ART) is made clinically, based on the WHO paediatric staging criteria, which were revised in 2006. Results of using new and old criteria were compared. Of 694 children, 626 (90.2%) fulfilled criteria to start ART when applying the new WHO staging guidelines, whereas 330 (47.6%) children were eligible for ART when using the old WHO criteria. This signifies a marked rise in the number of paediatric patients qualifying for ART on clinical grounds.
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http://dx.doi.org/10.1097/QAD.0b013e32832f7b39DOI Listing
September 2009