Publications by authors named "Virpi Glumoff"

32 Publications

Loss of DIAPH1 causes SCBMS, combined immunodeficiency, and mitochondrial dysfunction.

J Allergy Clin Immunol 2021 08 1;148(2):599-611. Epub 2021 Mar 1.

PEDEGO Research Unit, University of Oulu, Oulu, Finland.

Background: Homozygous loss of DIAPH1 results in seizures, cortical blindness, and microcephaly syndrome (SCBMS). We studied 5 Finnish and 2 Omani patients with loss of DIAPH1 presenting with SCBMS, mitochondrial dysfunction, and immunodeficiency.

Objective: We sought to further characterize phenotypes and disease mechanisms associated with loss of DIAPH1.

Methods: Exome sequencing, genotyping and haplotype analysis, B- and T-cell phenotyping, in vitro lymphocyte stimulation assays, analyses of mitochondrial function, immunofluorescence staining for cytoskeletal proteins and mitochondria, and CRISPR-Cas9 DIAPH1 knockout in heathy donor PBMCs were used.

Results: Genetic analyses found all Finnish patients homozygous for a rare DIAPH1 splice-variant (NM_005219:c.684+1G>A) enriched in the Finnish population, and Omani patients homozygous for a previously described pathogenic DIAPH1 frameshift-variant (NM_005219:c.2769delT;p.F923fs). In addition to microcephaly, epilepsy, and cortical blindness characteristic to SCBMS, the patients presented with infection susceptibility due to defective lymphocyte maturation and 3 patients developed B-cell lymphoma. Patients' immunophenotype was characterized by poor lymphocyte activation and proliferation, defective B-cell maturation, and lack of naive T cells. CRISPR-Cas9 knockout of DIAPH1 in PBMCs from healthy donors replicated the T-cell activation defect. Patient-derived peripheral blood T cells exhibited impaired adhesion and inefficient microtubule-organizing center repositioning to the immunologic synapse. The clinical symptoms and laboratory tests also suggested mitochondrial dysfunction. Experiments with immortalized, patient-derived fibroblasts indicated that DIAPH1 affects the amount of complex IV of the mitochondrial respiratory chain.

Conclusions: Our data demonstrate that individuals with SCBMS can have combined immune deficiency and implicate defective cytoskeletal organization and mitochondrial dysfunction in SCBMS pathogenesis.
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http://dx.doi.org/10.1016/j.jaci.2020.12.656DOI Listing
August 2021

Herpes simplex virus 2 encephalitis in a patient heterozygous for a TLR3 mutation.

Neurol Genet 2020 Dec 25;6(6):e532. Epub 2020 Nov 25.

Department of Internal Medicine (T.H., T.P.), Oulu University Hospital, Finland; Research Unit of Biomedicine (T.H., V.G., P.Å.), University of Oulu, Finland; St. Giles Laboratory of Human Genetics of Infectious Diseases (J.C., J.-L.C., S.-Y.Z.), Rockefeller Branch, The Rockefeller University, New York, NY; Department of Neurology (L.T., S.W.), Oulu University Hospital; Institute for Molecular Medicine Finland (J.L., J.S.), HiLIFE, and The Folkhälsan Research Center and Medicum (J.L.), University of Helsinki, Finland; Centre for Molecular Medicine Norway (J.S.), University of Oslo, Norway; Department of Clinical Genetics (M.K., O.K.), Oulu University Hospital, Finland; Department of Medical Microbiology (T.V.), Turku University Hospital and Institute of Biomedicine, University of Turku, Finland; Department of Clinical Neurophysiology (U.H.), Oulu University Hospital, Finland; Paris Descartes University (L.L., J.-L.C., S.-Y.Z.), Imagine Institute, Paris; Laboratory of Human Genetics of Infectious Diseases (J.-L.C., S.-Y.Z.), Necker Branch, INSERM UMR 1163, Necker Hospital for Sick Children, Paris; Pediatric Hematology-Immunology Unit (J.-L.C.), Necker Hospital for Sick Children, Paris, France; Howard Hughes Medical Institute (J.-L.C.), New York, NY; Adult Immunodeficiency Unit (M.R.J.S.), Infectious Diseases, Inflammation Center, University of Helsinki and HUS Helsinki University Hospital, Finland; and Rare Disease Center and Pediatric Research Center (M.R.J.S.), Children and Adolescents, University of Helsinki and HUS Helsinki University Hospital, Finland.

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http://dx.doi.org/10.1212/NXG.0000000000000532DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7720273PMC
December 2020

Respiratory viruses and febrile response in children with febrile seizures: A cohort study and embedded case-control study.

Seizure 2021 Jan 26;84:69-77. Epub 2020 Nov 26.

PEDEGO Research Unit (Research Unit for Pediatrics, Dermatology, Clinical Genetics, Obstetrics and Gynecology), Medical Research Center Oulu (MRC Oulu), University of Oulu, Oulu, Finland; Department of Pediatrics and Adolescent Medicine, Oulu University Hospital, Oulu, Finland; Biocenter Oulu, University of Oulu, Finland.

Objective: There are limited data on the pathogen-related and host-related factors in the pathogenesis of febrile seizures (FS). We designed a controlled study to compare the role of different respiratory viruses and febrile response in FS.

Methods: In a prospective cohort study of 1899 pediatric emergency room patients aged 6 months-6 years with a positive respiratory virus multiplex PCR, we identified 225 patients with FSs. We first compared the distribution of respiratory viruses in age-stratified patients with FSs with that in other patients. In an embedded case-control study, we compared the febrile response in patients with FSs with that in the controls matched for age, season and the same respiratory virus.

Results: The relative risk for FS was the highest for coronavirus OC43, 229E, and NL63 infections [RR: 3.2, 95 % confidence interval (CI): 1.4-7.2) and influenza A and B [RR: 2.5, 95 % CI: 1.4-4.7] as compared to those with other respiratory viral infections. The patients with FSs had a stronger febrile response of 39.2 °C (difference: 0.8 °C, 95 % CI: 0.5-1.2) later during hospitalization after acute care than the controls matched for the same respiratory virus.

Conclusions: Influenza and coronaviruses caused relatively more FS-related emergency room visits than other respiratory viruses. Furthermore, the febrile response was stronger in the patients with FSs than in the controls matched for the same respiratory virus. The results suggest that the pathomechanism of FSs includes modifiable pathogen-related and host-related factors with possible potential in the prevention of FSs.
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http://dx.doi.org/10.1016/j.seizure.2020.11.007DOI Listing
January 2021

Heterozygous TLR3 Mutation in Patients with Hantavirus Encephalitis.

J Clin Immunol 2020 11 16;40(8):1156-1162. Epub 2020 Sep 16.

Department of Internal Medicine, Oulu University Hospital, Oulu, Finland.

Puumala hantavirus (PUUV) hemorrhagic fever with renal syndrome (HFRS) is common in Northern Europe; this infection is usually self-limited and severe complications are uncommon. PUUV and other hantaviruses, however, can rarely cause encephalitis. The pathogenesis of these rare and severe events is unknown. In this study, we explored the possibility that genetic defects in innate anti-viral immunity, as analogous to Toll-like receptor 3 (TLR3) mutations seen in HSV-1 encephalitis, may explain PUUV encephalitis. We completed exome sequencing of seven adult patients with encephalitis or encephalomyelitis during acute PUUV infection. We found heterozygosity for the TLR3 p.L742F novel variant in two of the seven unrelated patients (29%, p = 0.0195). TLR3-deficient P2.1 fibrosarcoma cell line and SV40-immortalized fibroblasts (SV40-fibroblasts) from patient skin expressing mutant or wild-type TLR3 were tested functionally. The TLR3 p.L742F allele displayed low poly(I:C)-stimulated cytokine induction when expressed in P2.1 cells. SV40-fibroblasts from three healthy controls produced increasing levels of IFN-λ and IL-6 after 24 h of stimulation with increasing concentrations of poly(I:C), whereas the production of the cytokines was impaired in TLR3 L742F/WT patient SV40-fibroblasts. Heterozygous TLR3 mutation may underlie not only HSV-1 encephalitis but also PUUV hantavirus encephalitis. Such possibility should be further explored in encephalitis caused by these and other hantaviruses.
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http://dx.doi.org/10.1007/s10875-020-00834-2DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7567724PMC
November 2020

Tonsillar granuloma associated with hypogammaglobulinemia.

Allergy Asthma Clin Immunol 2020 29;16:43. Epub 2020 May 29.

Research Unit of Biomedicine, University of Oulu, Oulu, Finland.

Background: Rare tonsillar granulomas may be caused for example by infections, malignancies or sarcoidosis. Granulomas also occur in inborn errors of immunity (IEI) such as common variable immunodeficiency (CVID) with B cell maturation defects and hypogammaglobulinemia. CVID shares various features with sarcoidosis and drug-induced secondary hypogammaglobulinemia; careful consideration of differential diagnosis between these conditions is warranted.

Case Presentation: A 29-year-old female with epilepsy developed dysphagia, dyspnea and impaired exercise tolerance. Obstruction caused by swollen lingual tonsil and edema in the epiglottis and arytenoid mucosa were found. Lingual tonsil and epiglottis biopsies displayed non-necrotizing granulomas. There was no evidence of viral, bacterial, mycobacterial or fungal infections. Chest X-ray, computerized tomography of chest and ultrasound of neck and abdomen remained unremarkable. Positron emission tomography/computed tomography (PET/CT) showed laryngeal enhancement. Empiric antimicrobials combined with prednisolone were insufficient to control her disease. In immunological evaluation, the patient had normal counts of B and T cells. Proportions of CD27 memory B cells (30.3%) and IgDIgMCD27 switched memory B cells (7.2%; normal range 6.5-29.2%) were normal. Percentage of activated CD21 B cells was high (6.6%; normal range 0.6-3.5%). IgG (3.5 g/L; normal range 6.77-15.0 g/l) and all IgG subclass concentrations were low. Anti-polysaccharide responses were impaired, with 3/10 serotypes reaching a level of 0.35 µg/ml after immunization with Pneumovax. The findings were consistent with hypogammaglobulinemia resembling CVID, possibly secondary to antiepileptic medication. Her dyspnea and dysphagia responded favorably to subcutaneous IgG and rituximab.

Conclusions: Tonsillar granulomas can be the presenting and only clinical feature of B cell deficiency, highlighting the diversity of symptoms and findings in primary or secondary immunodeficiencies.
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http://dx.doi.org/10.1186/s13223-020-00441-1DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7257222PMC
May 2020

A Family With A20 Haploinsufficiency Presenting With Novel Clinical Manifestations and Challenges for Treatment.

J Clin Rheumatol 2021 Dec;27(8):e583-e587

Department of Rheumatology, Inflammation Center, University of Helsinki and Helsinki University Hospital. Research Institute, Invalid Foundation. Orton Orthopedic Hospital.

Background: Tumor necrosis factor α-induced protein 3 gene (TNFAIP3, also called A20) haploinsufficiency (HA20) leads to autoinflammation and autoimmunity. We have recently shown that a p.(Lys91*) mutation in A20 disrupts nuclear factor κB signaling, impairs protein-protein interactions of A20, and leads to inflammasome activation.

Methods: We now describe the clinical presentations and drug responses in a family with HA20 p.(Lys91*) mutation, consistent with our previously reported diverse immunological and functional findings.

Results: We report for the first time that inflammasome-mediated autoinflammatory lung reaction caused by HA20 can be treated with interleukin 1 antagonist anakinra. We also describe severe anemia related to HA20 successfully treated with mycophenolate. In addition, HA20 p.(Lys91*) was found to associate with autoimmune thyroid disease, juvenile idiopathic arthritis, psoriasis, liver disease, and immunodeficiency presenting with specific antibody deficiency and genital papillomatosis.

Conclusions: We conclude that HA20 may lead to combination of inflammation, immunodeficiency, and autoimmunity. The condition may present with variable and unpredictable symptoms with atypical treatment responses.
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http://dx.doi.org/10.1097/RHU.0000000000001268DOI Listing
December 2021

Cord blood cytokine profile is associated with the risk of asthma at the age of 8 years.

Acta Paediatr 2020 06 7;109(6):1271-1272. Epub 2020 Jan 7.

PEDEGO Research Unit, Medical Research Centre Oulu, University of Oulu, Oulu, Finland.

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http://dx.doi.org/10.1111/apa.15141DOI Listing
June 2020

Dominant TOM1 mutation associated with combined immunodeficiency and autoimmune disease.

NPJ Genom Med 2019 27;4:14. Epub 2019 Jun 27.

1Institute of Biotechnology, University of Helsinki, Helsinki, Finland.

Mutations in several proteins functioning as endolysosomal components cause monogenic autoimmune diseases, of which pathogenesis is linked to increased endoplasmic reticulum stress, inefficient autophagy, and defective recycling of immune receptors. We report here a heterozygous p.G307D missense mutation, detected by whole-exome sequencing, in two related patients presenting with early-onset autoimmunity, antibody deficiency, and features of combined immunodeficiency. The index patient suffered from recurrent respiratory tract infections and oligoarthritis since early teens, and later developed persistent low-copy EBV-viremia, as well as an antibody deficiency. Her infant son developed hypogammaglobulinemia, autoimmune enteropathy, interstitial lung disease, profound growth failure, and treatment-resistant psoriasis vulgaris. Consistent with previous knowledge on TOM1 protein function, we detected impaired autophagy and enhanced susceptibility to apoptosis in patient-derived cells. In addition, we noted diminished STAT and ERK1/2 signaling in patient fibroblasts, as well as poor IFN-γ and IL-17 secretion in T cells. The mutant TOM1 failed to interact with TOLLIP, a protein required for IL-1 recycling, PAMP signaling and autophagosome maturation, further strengthening the link between the candidate mutation and patient pathophysiology. In sum, we report here an identification of a novel gene, , associating with early-onset autoimmunity, antibody deficiency, and features of combined immunodeficiency. Other patient cases from unrelated families are needed to firmly establish a causal relationship between the genotype and the phenotype.
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http://dx.doi.org/10.1038/s41525-019-0088-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6597545PMC
June 2019

The Pro-Oncogenic Adaptor CIN85 Acts as an Inhibitory Binding Partner of Hypoxia-Inducible Factor Prolyl Hydroxylase 2.

Cancer Res 2019 08 29;79(16):4042-4056. Epub 2019 May 29.

Faculty of Biochemistry and Molecular Medicine and Biocenter Oulu, University of Oulu, Oulu, Finland.

The EGFR adaptor protein, CIN85, has been shown to promote breast cancer malignancy and hypoxia-inducible factor (HIF) stability. However, the mechanisms underlying cancer promotion remain ill defined. Here we show that CIN85 is a novel binding partner of the main HIF-prolyl hydroxylase, PHD2, but not of PHD1 or PHD3. Mechanistically, the N-terminal SRC homology 3 domains of CIN85 interacted with the proline-arginine-rich region within the N-terminus of PHD2, thereby inhibiting PHD2 activity and HIF degradation. This activity is essential , as specific loss of the CIN85-PHD2 interaction in CRISPR/Cas9-edited cells affected growth and migration properties, as well as tumor growth in mice. Overall, we discovered a previously unrecognized tumor growth checkpoint that is regulated by CIN85-PHD2 and uncovered an essential survival function in tumor cells by linking growth factor adaptors with hypoxia signaling. SIGNIFICANCE: This study provides unprecedented evidence for an oxygen-independent mechanism of PHD2 regulation that has important implications in cancer cell survival. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/79/16/4042/F1.large.jpg.
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http://dx.doi.org/10.1158/0008-5472.CAN-18-3852DOI Listing
August 2019

Haploinsufficiency of A20 impairs protein-protein interactome and leads into caspase-8-dependent enhancement of NLRP3 inflammasome activation.

RMD Open 2018 17;4(2):e000740. Epub 2018 Oct 17.

Institute of Biotechnology, Helsinki Institute of Life Science (HiLIFE), University of Helsinki, Helsinki, Finland.

Objectives: encodes A20 that negatively regulates nuclear factor kappa light chain enhancer of activated B cells (NF-κB), the major transcription factor coordinating inflammatory gene expression. polymorphisms have been linked with a spectrum of inflammatory and autoimmune diseases and, recently, loss-of-function mutations in A20 were found to cause a novel inflammatory disease 'haploinsufficiency of A20' (HA20). Here we describe a family with HA20 caused by a novel loss-of-function mutation and elucidate the upstream molecular mechanisms linking HA20 to dysregulation of NF-κB and the related inflammasome pathway.

Methods: NF-κB activation was studied in a mutation-expressing cell line using luciferase reporter assay. Physical and close-proximity protein-protein interactions of wild-type and p.(Lys91*) mutant A20 were analysed using mass spectrometry. NF-κB -dependent transcription, cytokine secretion and inflammasome activation were compared in immune cells of the HA20 patients and control subjects.

Results: The protein-protein interactome of p.(Lys91*) mutant A20 was severely impaired, including interactions with proteins regulating NF-κB activation, DNA repair responses and the NLR family pyrin domain containing 3 (NLRP3) inflammasome. The p.(Lys91*) mutant A20 failed to suppress NF-κB signalling, which led to increased NF-κB -dependent proinflammatory cytokine transcription. Functional experiments in the HA20 patients' immune cells uncovered a novel caspase-8-dependent mechanism of NLRP3 inflammasome hyperresponsiveness that mediated the excessive secretion of interleukin-1β and interleukin-18.

Conclusions: The current findings significantly deepen our understanding of the molecular mechanisms underlying HA20 and other diseases associated with reduced A20 expression or function, paving the way for future therapeutic targeting of the pathway.
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http://dx.doi.org/10.1136/rmdopen-2018-000740DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6203104PMC
October 2018

Nitazoxanide May Modify the Course of Progressive Multifocal Leukoencephalopathy.

J Clin Immunol 2018 01 20;38(1):4-6. Epub 2017 Nov 20.

Immunodeficiency Unit, Inflammation Center and Center for Rare Diseases, Children's Hospital, Helsinki University and Helsinki University Hospital, Helsinki, Finland.

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http://dx.doi.org/10.1007/s10875-017-0463-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7086546PMC
January 2018

Damaging heterozygous mutations in NFKB1 lead to diverse immunologic phenotypes.

J Allergy Clin Immunol 2017 Sep 21;140(3):782-796. Epub 2017 Jan 21.

Adult Immunodeficiency Unit, Infectious Diseases, Inflammation Center, University of Helsinki and Helsinki University Hospital, Helsinki, Finland; Rare Diseases Center, Children's Hospital, University of Helsinki and Helsinki University Hospital, Helsinki, Finland.

Background: The nuclear factor κ light-chain enhancer of activated B cells (NF-κB) signaling pathway is a key regulator of immune responses. Accordingly, mutations in several NF-κB pathway genes cause immunodeficiency.

Objective: We sought to identify the cause of disease in 3 unrelated Finnish kindreds with variable symptoms of immunodeficiency and autoinflammation.

Methods: We applied genetic linkage analysis and next-generation sequencing and functional analyses of NFKB1 and its mutated alleles.

Results: In all affected subjects we detected novel heterozygous variants in NFKB1, encoding for p50/p105. Symptoms in variant carriers differed depending on the mutation. Patients harboring a p.I553M variant presented with antibody deficiency, infection susceptibility, and multiorgan autoimmunity. Patients with a p.H67R substitution had antibody deficiency and experienced autoinflammatory episodes, including aphthae, gastrointestinal disease, febrile attacks, and small-vessel vasculitis characteristic of Behçet disease. Patients with a p.R157X stop-gain experienced hyperinflammatory responses to surgery and showed enhanced inflammasome activation. In functional analyses the p.R157X variant caused proteasome-dependent degradation of both the truncated and wild-type proteins, leading to a dramatic loss of p50/p105. The p.H67R variant reduced nuclear entry of p50 and showed decreased transcriptional activity in luciferase reporter assays. The p.I553M mutation in turn showed no change in p50 function but exhibited reduced p105 phosphorylation and stability. Affinity purification mass spectrometry also demonstrated that both missense variants led to altered protein-protein interactions.

Conclusion: Our findings broaden the scope of phenotypes caused by mutations in NFKB1 and suggest that a subset of autoinflammatory diseases, such as Behçet disease, can be caused by rare monogenic variants in genes of the NF-κB pathway.
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http://dx.doi.org/10.1016/j.jaci.2016.10.054DOI Listing
September 2017

Clinical Efficiency of Topical Calcipotriol/Betamethasone Treatment in Psoriasis Relies on Suppression of the Inflammatory TNFα - IL-23 - IL-17 Axis.

Acta Derm Venereol 2017 Apr;97(4):449-455

PEDEGO Research Unit, Oulu Center for Cell-Matrix Research, Department of Dermatology and Medical Research Center Oulu, Oulu University Hospital and University of Oulu, FIN-90029 Oulu, Finland.

The effects of topical calcipotriol/betamethasone combination therapy and betamethasone monotherapy on inflammatory T-cell numbers and molecular markers were compared in patients with psoriasis. Combination therapy down-regulated the expression of tumour necrosis factor (TNF)-α, interleukin (IL)-23A, IL-17A, S100A7, CCL-20 and interferon (IFN)-γ in skin and TNF-α, IL-6, IL-23A, T-bet and IFN-γ in peripheral blood mononuclear cells (PBMCs). Betamethasone monotherapy had less effect. Expression of FoxP3 in both skin and PBMCs was down-regulated by calcipotriol/betamethasone, but not by betamethasone. Immunohistochemical analysis revealed that calcipotriol/betamethasone reduced the numbers of CD4+ and CD8+ T cells and Tregs in psoriatic lesions more than betamethasone. Flow cytometric analyses demonstrated that calcipotriol/betamethasone decreased the numbers of circulating CD8+ T cells, Tregs, skin-homing Th17 memory cells and Th22 memory cells, while betamethasone had little or no effect. Glucocorticoid receptors GRα and GRß were expressed in psoriatic skin. In conclusion, calcipotriol increases the immunosuppressive power of betamethasone by suppressing the inflammatory TNF-α - IL-23 - IL-17 axis.
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http://dx.doi.org/10.2340/00015555-2579DOI Listing
April 2017

Expression of Glucocorticoid Receptors GRα and GRβ in Bullous Pemphigoid.

Acta Derm Venereol 2016 Nov;96(7):922-926

Department of Dermatology, University of Oulu, FIN-90029 Oulu, Finland.

First-line treatments of bullous pemphigoid (BP) are topical and systemic glucocorticoids (GC). The actions of GC are mediated by glucocorticoid receptors (GR), which exist in several isoforms, of which GRα and GRβ are the most important. In many inflammatory diseases, up-regulation of GRβ is associated with GC insensitivity. The aims of this study were to determine the expression of GRα and GRβ in patients with BP and to investigate the effect of prednisolone treatment on the expression of GR isoforms in BP. Quantitative real-time PCR (qPCR) analysis demonstrated that GR isoform mRNAs are expressed in peripheral blood mononuclear cells (PBMC) from patients with BP. Expression of GRα and GRβ protein was confirmed by immunohistochemical staining of BP skin biopsies and by Western blot analysis and flow cytometric analysis of PBMCs. During prednisolone treatment, GRα and GRβ expression varied markedly, but changes were not suitable as a clinical marker of GC sensitivity in patients with BP.
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http://dx.doi.org/10.2340/00015555-2443DOI Listing
November 2016

Microbes of the tonsils in PFAPA (Periodic Fever, Aphtous stomatitis, Pharyngitis and Adenitis) syndrome - a possible trigger of febrile episodes.

APMIS 2015 Jun 23;123(6):523-9. Epub 2015 Apr 23.

Department of Pediatrics, Oulu University Hospital and Medical Research Center, University of Oulu, Oulu, Finland.

Periodic Fever, Aphtous stomatitis, Pharyngitis, and Adenitis (PFAPA) is a childhood febrile syndrome that is often cured by tonsillectomy (TE). We hypothesized that microbes present in the tonsils may act as a trigger for the activation of inflammasomes and investigated the microbiology of the tonsils in PFAPA patients and controls. We recruited 31 consecutive children who underwent TE due to PFAPA; 24 children who underwent TE due to other reasons served as controls. We cultured all the samples for bacteria, mycobacteria, yeasts, and viruses and used PCR for 15 viruses. Also biofilm formation and histologic findings were identified. The samples of the patients yielded Candida albicans more often than did the controls (16 vs 0%, p = 0.003). Staphylococcus aureus occurred in only 10% of the patients, but in 38% of the controls (p = 0.01). Varicella zoster and Herpes simplex viruses occurred less often in patients than in controls. Biofilm was present in 55% of PFAPA tonsils, but in only 24% of the controls (p = 0.03). The microbes found in the tonsils of PFAPA patients showed significant differences from those of controls. This may in part explain the efficacy of TE in PFAPA.
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http://dx.doi.org/10.1111/apm.12383DOI Listing
June 2015

CD4⁺ T-cell proliferation responses to wheat polypeptide stimulation in children at different stages of type 1 diabetes autoimmunity.

Pediatr Diabetes 2015 May 30;16(3):177-88. Epub 2015 Jan 30.

Department of Pediatrics, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland; Department of Medical Microbiology and Immunology, Medical Research Center Oulu, Oulu University Hospital and University of Oulu, Oulu, Finland.

Aims: Our aim was to study whether immune responses to wheat-based proteins are related to the development of type 1 diabetes.

Methods: We analysed proliferative T-cell responses after in vitro gliadin, gluten, whole wheat, and tetanus toxoid stimulation with a carboxyfluorescein succinimidyl ester (CFSE) based T-cell proliferation assay in children at various phases of type 1 diabetes autoimmunity and in healthy autoantibody-negative control children.

Results: At an early stage of beta cell autoimmunity the strength and frequencies of positive proliferation responses to gliadin, gluten, and whole wheat did not differ between newly seroconverted children positive for one islet autoantibody and the controls. However, in prediabetic children with at least two islet autoantibodies and also in children with newly diagnosed type 1 diabetes positive T-cell responses to gliadin were significantly less frequent and the strength of gliadin responses was reduced when compared to the controls. No differences were seen in T-cell responses to wheat-based antigens when comparing children with long-lasting type 1 diabetes with healthy controls.

Conclusions/interpretation: Decreased in vitro T-cell responses to wheat-based antigens were observed in children with multiple islet autoantibodies and in those with newly diagnosed type 1 diabetes, probably reflecting a generally aberrant immune response during the development of type 1 diabetes.
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http://dx.doi.org/10.1111/pedi.12256DOI Listing
May 2015

Autoimmunity, hypogammaglobulinemia, lymphoproliferation, and mycobacterial disease in patients with activating mutations in STAT3.

Blood 2015 Jan 27;125(4):639-48. Epub 2014 Oct 27.

Folkhälsan Institute of Genetics and Research Programs Unit, Molecular Neurology, and Department of Biosciences and Nutrition, and Center for Innovative Medicine, Karolinska Institutet, Stockholm, Sweden.

The signal transducer and activator of transcription (STAT) family of transcription factors orchestrate hematopoietic cell differentiation. Recently, mutations in STAT1, STAT5B, and STAT3 have been linked to development of immunodysregulation polyendocrinopathy enteropathy X-linked-like syndrome. Here, we immunologically characterized 3 patients with de novo activating mutations in the DNA binding or dimerization domains of STAT3 (p.K392R, p.M394T, and p.K658N, respectively). The patients displayed multiorgan autoimmunity, lymphoproliferation, and delayed-onset mycobacterial disease. Immunologically, we noted hypogammaglobulinemia with terminal B-cell maturation arrest, dendritic cell deficiency, peripheral eosinopenia, increased double-negative (CD4(-)CD8(-)) T cells, and decreased natural killer, T helper 17, and regulatory T-cell numbers. Notably, the patient harboring the K392R mutation developed T-cell large granular lymphocytic leukemia at age 14 years. Our results broaden the spectrum of phenotypes caused by activating STAT3 mutations, highlight the role of STAT3 in the development and differentiation of multiple immune cell lineages, and strengthen the link between the STAT family of transcription factors and autoimmunity.
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http://dx.doi.org/10.1182/blood-2014-04-570101DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4304109PMC
January 2015

TIM-family molecules in embryonic hematopoiesis: fetal liver TIM-4(lo) cells have myeloid potential.

Exp Hematol 2014 Mar 4;42(3):230-40. Epub 2013 Dec 4.

Institute of Diagnostics, Department of Medical Microbiology and Immunology, University of Oulu, Oulu, Finland.

Trans-membrane (or T cell) immunoglobulin and mucin (TIM) molecules are known regulators of immune response whose function in hematopoiesis is unknown. Earlier, we found that tim-1 and tim-4 are expressed by CD45(+) cells in the para-aortic region of chicken embryo. Because the para-aortic region is a known site for hematopoietic stem cell (HSC) and hematopoietic progenitor cell (HPC) differentiation and expansion, we hypothesize that TIM molecules have a role in hematopoiesis. To study this role further, we analyzed TIM expression more precisely in chicken para-aortic region and mouse fetal liver hematopoietic cells. Additionally, we examined the hematopoietic potential of TIM-4(+) mouse fetal liver cells with a colony-forming assay. tim-1 gene expression was detected in chicken and mouse embryos in the aorta-gonads-mesonephros-region at the time of HSC emergence, whereas tim-3 mRNA was widely expressed in different tissues. tim-4 expression was restricted to fetal liver CD45(+)F4/80(+) cells. Moreover, two TIM-4(+) populations were distinguished: F4/80(hi)TIM-4(hi) and F4/80(lo)TIM-4(lo). F4/80(hi)TIM-4(hi) cells had no hematopoietic potential and were morphologically similar to mature macrophages, suggesting that they are yolk sac-derived macrophages. Instead, many of the F4/80(lo)TIM-4(lo) cells were c-kit(+) and Sca-1(+) and had primitive morphology and multilineage colony-forming ability. In addition, F4/80(lo)TIM-4(lo) cells included a considerable population expressing ER-MP12, a known marker for macrophage colony-forming cells and other myeloid progenitors. We conclude that TIM molecules are expressed in embryonic hematopoietic tissues in chicken and mouse and that in fetal liver, TIM-4 is expressed by myeloid progenitor cells.
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http://dx.doi.org/10.1016/j.exphem.2013.11.014DOI Listing
March 2014

Central nervous system-related symptoms and findings are common in acute Puumala hantavirus infection.

Ann Med 2010 Jul;42(5):344-51

Department of Internal Medicine, Oulu University Hospital, Oulu, Finland.

Background: Puumala hantavirus (PUUV) causes a hemorrhagic fever with renal syndrome (HFRS) also called nephropathia epidemica (NE). Recent case reports and retrospective studies suggest that NE may damage the pituitary gland. Based on these observations, our goal was to explore the nature of this complication prospectively.

Methods: A total of 58 hospitalized patients with acute NE volunteered to participate. Central nervous system (CNS) symptoms were recorded, cerebrospinal fluid (CSF) samples were collected, human leukocyte antigen (HLA) haplotype was analyzed, brain magnetic resonance imaging (MRI) was acquired, and electroencephalography (EEG) was recorded. Patients with abnormal pituitary MRI finding were examined by an endocrinologist.

Results: Most patients experienced CNS symptoms, and half of the CSF samples were positive for PUUV IgM, elevated protein level, or leukocyte count. CSF of patients negative for DR15(2)-DQ6 haplotype was less frequently affected. MRI revealed pituitary hemorrhage in two patients; these two patients suffered sudden loss of vision associated with headache, and they both developed hypopituitarism. Only one patient required long-term hormonal replacement therapy.

Conclusion: CNS-related symptoms and inflammation in the CSF are common in acute NE. Genetic properties of the host may predispose to CNS involvement. It does seem that pituitary injury and subsequent hormonal insufficiency may complicate the recovery.
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http://dx.doi.org/10.3109/07853890.2010.480979DOI Listing
July 2010

Nasal middle meatal specimen bacteriology as a predictor of the course of acute respiratory infection in children.

Pediatr Infect Dis J 2006 Feb;25(2):108-12

Departments of Otorhinolaryngology, PO Box 5000, University of Oulu, Oulu FIN-90014, Finland.

Aims: To test our hypothesis that children with potentially pathogenic bacteria (Streptococcus pneumoniae, Haemophilus influenzae or Moraxella catarrhalis) in the nasal middle meatus might have more prolonged symptoms of acute respiratory infection than children without such bacteria, we conducted a prospective cohort study of such children.

Materials And Methods: We recruited prospectively child volunteers between 6 and 13 years of age with acute respiratory infections present for fewer than 10 days. Nasal middle meatal bacterial culture was taken with a rigid endoscope at enrollment and again after 3 weeks and evaluated for presence or absence of 3 potential pathogens: S. pneumoniae, H. influenzae and M. catarrhalis. The subsequent persistence of acute symptoms (nasal discharge: clear/colored, nasal obstruction and cough) was determined by means of a diary. Viral etiology was studied with polymerase chain reaction methods.

Results: The 82 children had had symptoms for an average of 4 days (range, 1-10) at entry, and viruses were detected in 54% (39 of 72). The endoscopic procedure and bacteriologic sampling succeeded in all cases. Thirty-eight children (46%) had at least 1 of the 3 pathogens in the middle meatus specimen. The children with nasal pathogens present at entry had a significantly longer mean duration of symptoms than those with nonpathogenic bacteria (difference, 3.6 days; 95% confidence interval, 0.7-6.5; P = 0.025). The effect remained significant after adjustment for age, sex, allergic symptoms and the presence of virus (adjusted relative hazard of delayed recovery, 2.0; 95% confidence interval, 1.1-3.6).

Conclusions: We found that the use of endoscopic swab culture sampling from the nasal middle meatus is well-tolerated by children older than 6 years of age and that it can be useful in selected situations to determine pathogenic bacteria in the culture of these specimens.
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http://dx.doi.org/10.1097/01.inf.0000201048.65828.b5DOI Listing
February 2006

Mechanism of acute fetal cardiovascular depression after maternal inflammatory challenge in mouse.

Am J Pathol 2005 Jun;166(6):1585-92

Department of Pediatrics and Biocenter Oulu, P.O. Box 5000, FIN-90014 University of Oulu, Finland.

Intra-amniotic lipopolysaccharide (LPS) causes an acute inflammatory response and cardiac dysfunction in fetal mice. We hypothesized that the placenta protects the fetus against maternally administered bacterial toxins, delaying the onset of a fetal inflammatory response and vascular compromise. At 14 to 15 days of gestation, DBA mice were randomized to receive LPS (2.4 mg/kg) or vehicle intraperitoneally. Doppler ultrasonography of fetal cardiovascular hemodynamics was performed before and 6 hours after maternal LPS. Six hours after the LPS, maternal serum concentrations of tumor necrosis factor-alpha and interleukin (IL)-6 (P < 0.05) were increased. Placenta showed severe maternal vascular dilatation and congestion. The expressions of tumor necrosis factor-alpha, IL-1alpha, and IL-6 (P < 0.05) were increased, and the expression of Toll-like receptor 4 was constitutive in placenta. The expression of Toll-like receptor 2 increased (P < 0.05) and was detected in labyrinthine macrophages. No inflammatory activation was found in fetal tissues, and amniotic fluid revealed no significant increase in cytokines. The ultrasonographic examination demonstrated increased fetal cardiac afterload after LPS, with 65% of the fetuses exhibiting atrioventricular valve regurgitation. In conclusion, maternal inflammatory insult activates placental labyrinthine macrophages leading to an acute increase in placental vascular resistance and fetal cardiac dysfunction without an inflammatory response in fetus.
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http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1602402PMC
http://dx.doi.org/10.1016/S0002-9440(10)62469-8DOI Listing
June 2005

Detection of human picornaviruses by multiplex reverse transcription-PCR and liquid hybridization.

J Clin Microbiol 2005 Mar;43(3):1239-45

Department of Virology, Haartman Institute, University of Helsinki, P.O. Box 21, FIN-00014 Helsinki, Finland.

A qualitative multiplex reverse transcription (RT)-PCR and liquid hybridization assay for the detection of human enteroviruses, rhinoviruses, parechoviruses, and Aichi virus was developed. Furthermore, a separate assay for the recognition of hepatitis A virus was established to complement the test pattern so that all human picornaviruses were covered. The amplicons, which represented the 5' untranslated regions of the viral RNA genomes, were identified in liquid hybridization reactions with genus-specific digoxigenin-labeled oligonucleotide probes. The sensitivity of the multiplex RT-PCR and liquid hybridization assay was 10 to 100 picornavirus genome equivalents for representatives of each picornavirus genus. The hepatitis A virus assay exhibited a sensitivity of 10 genome copies. Both the uniplex and the multiplex tests were highly specific for the target viruses. Twenty-three clinical samples, including cerebrospinal fluid, serum, and nasopharyngeal swab specimens, were used for clinical evaluation of the multiplex RT-PCR assay. The results obtained were consistent with the results of routine virus diagnostic assays. Furthermore, the assay was used to screen 68 stool specimens for the presence of parechoviruses and Aichi virus. One sample was found to contain parechovirus RNA, whereas no Aichi virus was detected. The assay described here can be applied for the efficient identification of human enteroviruses and rhinoviruses in clinical specimens and simultaneously enables the collection of information on the epidemiology and clinical outcomes of infections caused by the currently poorly known human parechoviruses and Aichi virus.
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http://dx.doi.org/10.1128/JCM.43.3.1239-1245.2005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1081250PMC
March 2005

Expression of toll-like receptor 4 and endotoxin responsiveness in mice during perinatal period.

Pediatr Res 2005 May 17;57(5 Pt 1):644-8. Epub 2005 Feb 17.

Department of Pediatrics and Biocenter Oulu, University of Oulu, FIN-90014 Oulu, Finland.

Endotoxin [lipopolysaccharide (LPS)] from Gram-negative bacteria is found in amniotic fluid in intrauterine infections that associate with the risk for spontaneous premature birth, bronchopulmonary dysplasia (BPD), and respiratory distress syndrome. Toll-like receptor 4 (TLR4) is the signaling receptor for LPS. The aim was to investigate the primary inflammatory response in mice shortly after administration of LPS to the dam (14 and 17 d of pregnancy), to the newborn, or into the amniotic fluid. The expression levels of TLR4, IL-1, tumor necrosis factor-alpha, IL-6, IL-10, macrophage inflammatory protein-2, and IL-1 receptor 1 were studied with ribonuclease protection assay. In addition, TLR4 protein was analyzed with Western blotting. The fetal membranes expressed TLR4 mRNA and protein and showed an acute cytokine response to LPS when LPS was administrated into the amniotic fluid. There was distinct ontogeny in the responsiveness of fetal lung to LPS: on fetal day 14 (term 20 d), both the expression of TLR4 and the acute cytokine response were undetectable 5 h after LPS; they became detectable by fetal day 17. TLR4 and the cytokine response further increased after birth. In maternal lung, the TLR4 expression was strongest and up-regulated in parallel with the induction of the cytokines. We propose that TLR4 controls the magnitude of the LPS-induced cytokine response during the perinatal period.
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http://dx.doi.org/10.1203/01.PDR.0000156212.03459.A9DOI Listing
May 2005

Transcription factors NF-kappaB and C/EBPdelta and IL-1-induced expression of surfactant protein A in lung explants during the perinatal period.

Biol Neonate 2005 24;87(3):152-9. Epub 2004 Nov 24.

Department of Pediatrics and Biocenter Oulu, University of Oulu, Oulu, Finland.

Interleukin-1 (IL-1) increases the expression of surfactant protein A (SP-A) in rabbit, lamb and human fetal lung. The upregulation disappears towards term. Among the transcription factors, IL-1 activates nuclear factor kappaB (NF-kappaB) and CCAAT/enhancer-binding protein delta (C/EBPdelta). NF-kappaB presumably has a role in IL-1-induced upregulation of SP-A. Also, C/EBPdelta may regulate SP-A expression. The aim was to study the role of these transcription factors in the induced effect of IL-1 on SP-A expression. Explants from fetal and neonatal rabbit lung were cultured in vitro followed by studies using immunohistochemistry, electrophoretic mobility shift assay and Northern analysis. We found gestation-dependent changes in IL-1-induced immunoreactivities of NF-kappaB and C/EBPdelta in the nuclei of alveolar cells. This increase in nuclear transcription factors correlated with IL-1-induced SP-A expression levels. As studied in the explants from fetal and newborn lung, the SP-A mRNA expression additionally associated with C/EBPdelta mRNA and with the binding of nuclear extracts from the lung explants to the C/EBP consensus probe. On the basis of the present and previous studies, we propose that NF-kappaB and C/EBPdelta have potential mediator roles in IL-1-induced upregulation of SP-A in immature lung.
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http://dx.doi.org/10.1159/000082312DOI Listing
July 2005

Inflammatory and anti-inflammatory responsiveness of surfactant proteins in fetal and neonatal rabbit lung.

Pediatr Res 2004 Jan 6;55(1):55-60. Epub 2003 Nov 6.

Department of Pediatrics and Biocenter Oulu, University of Oulu, Kajaanintie 52, 90220 Oulu, Finland.

Spontaneous preterm birth due to intrauterine infection is associated with increased concentrations of cytokines in amniotic fluid and in the airways at birth. Intra-amniotic IL-1 induces fetal lung maturity, consistent with the decrease in the incidence of respiratory distress syndrome (RDS) in intrauterine inflammation. On the other hand, antenatal corticosteroid decreases the incidence of RDS in infants born prematurely. The aim of the present study was to investigate the interaction between IL-1 and glucocorticoid in the expression of the surfactant proteins SP-A, -B, and -C. Lung explants from rabbit fetuses at 22 (immature), 27 (transitional), and 30 (mature) d of gestation (term, 30-31 d) and on d 1 after term birth were cultured with dexamethasone (Dx), IL-1alpha, or vehicle in the presence or absence of actinomycin D. According to the present results, IL-1alpha and Dx additively increased the expression of SP-A and SP-B on d 22. Later in gestation, SP-B and SP-C were suppressed by IL-1, whereas glucocorticoid tended to increase the expression of SP-B and SP-C and prevented the IL-1-induced suppression of SP. IL-1alpha and steroid interactively increased the stability of SP mRNA compared with the single agonist, possibly explaining the additive effects on the SP mRNA levels. The present results reveal beneficial additive effects of glucocorticoid and cytokine on lung surfactant. They may explain some of the acute beneficial effects of glucocorticoid therapy in chorioamnionitis before premature birth and in inflammatory lung disease after birth.
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http://dx.doi.org/10.1203/01.PDR.0000100462.41671.C6DOI Listing
January 2004

Intra-amniotic lipopolysaccharide leads to fetal cardiac dysfunction. A mouse model for fetal inflammatory response.

Cardiovasc Res 2003 Oct;60(1):156-64

Department of Pediatrics and Biocenter Oulu, University of Oulu, P.O. Box 5000, FIN-90014, Oulu, Finland.

Objective: Intrauterine infection is associated with increased lipopolysaccharide (LPS) and proinflammatory cytokines in amniotic fluid. We hypothesized that intra-amniotic LPS launches a fetal inflammatory response leading to cardiac dysfunction.

Methods: A mouse model was established. At 15-16 days of gestation, 52 fetuses of nine dams received LPS and 46 fetuses of nine dams vehicle intra-amniotically. Five dams underwent a sham operation. Echocardiography was performed before and 6 h after the injection to obtain inflow and outflow blood velocity waveforms. Outflow mean velocity (V(mean)) and the proportions of isovolumetric relaxation (IRT%) and contraction (ICT%) times of the cardiac cycle were calculated. Pulsatility indices (PI) were calculated from the umbilical and intracranial arteries and the descending aorta. Pulsatility indices for veins (PIV) were obtained from ductus venosus. Toll-like receptor-4 (TLR4) and several other inflammatory mediators were determined using ELISA, immunohistochemistry, or ribonuclease protection assay.

Results: In the LPS group, outflow V(mean) was significantly lower, and ICT% and IRT% longer than in the other groups. LPS increased PIs, except in the intracranial arteries, which showed a decrease in PIs. In ductus venosus, PIVs were increased after LPS. LPS increased interleukin (IL)-6 in amniotic fluid and induced the expression of proinflammatory cytokines in placenta and fetal membranes, but not in lung. In fetal myocardium, TLR4 was constitutional. LPS induced the expression of IL-1beta and tumor necrosis factor (TNF)-alpha mRNA in myocardium, whereas inducible nitric oxide synthase (NOS2) protein and nitrotyrosine remained undetectable.

Conclusions: As a response to endotoxin in amniotic fluid, fetal myocardium acutely generates cytokines and severe fetal cardiovascular compromise develops. These two may be linked through a mechanism that does not include NO.
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http://dx.doi.org/10.1016/s0008-6363(03)00338-9DOI Listing
October 2003

Phosphatidylinositol 3-kinase is involved in Toll-like receptor 4-mediated cytokine expression in mouse macrophages.

Eur J Immunol 2003 Mar;33(3):597-605

Biocenter Oulu and Department of Pediatrics, University of Oulu, PO Box 5000, FIN-90014 Oulu, Finland.

Recent evidence suggests a role for phosphatidylinositol (PI) 3-kinase in various inflammatory responses. In this study, the consequences of LPS-induced PI 3-kinase activation on cytokine and chemokine expression and the intracellular mechanisms of inflammatory activation were examined in mouse macrophages. LPS stimulation induced a complex formation between PI 3-kinase and myeloid differentiation factor 88 (MyD88), which was followed by an induction of IL-1beta, tumor necrosis factor-alpha (TNF-alpha) and macrophage inflammatory protein (MIP)-2. The induction of IL-1beta, but not of MIP-2 or TNF-alpha, was blocked by the PI 3-kinase inhibitors LY294002 and wortmannin. The nuclear factor-kappaB (NF-kappaB) inhibitor pyrrolidinedithiocarbamate (PDTC) blocked the induction of IL-1beta and TNF-alpha, but had no effect on MIP-2 expression. Inhibition of PI 3-kinase decreased the LPS-induced transcriptional activity of NF-kappaB, but it had no effect on the nuclear DNA binding activity of NF-kappaB. These findings suggest that, while NF-kappaB nuclear localization and DNA binding are necessary, they are not sufficient for transcriptional activation of the IL-1beta gene in the absence of PI 3-kinase activity. Taken together, our results demonstrate that activation of Toll-like receptor (TLR)-4 results in PI 3-kinase-MyD88 complex formation, and that PI 3-kinase activity selectively leads to cytokine induction downstream of TLR4.
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http://dx.doi.org/10.1002/eji.200323376DOI Listing
March 2003
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