Publications by authors named "Alexandra H Filipovich"

102 Publications

PAX1 is essential for development and function of the human thymus.

Sci Immunol 2020 02;5(44)

Laboratory of Clinical Immunology and Microbiology, NIAID, NIH, Bethesda, MD 20892, USA.

We investigated the molecular and cellular basis of severe combined immunodeficiency (SCID) in six patients with otofaciocervical syndrome type 2 who failed to attain T cell reconstitution after allogeneic hematopoietic stem cell transplantation, despite successful engraftment in three of them. We identified rare biallelic rare variants in all patients. We demonstrated that these mutant PAX1 proteins have an altered conformation and flexibility of the paired box domain and reduced transcriptional activity. We generated patient-derived induced pluripotent stem cells and differentiated them into thymic epithelial progenitor cells and found that they have an altered transcriptional profile, including for genes involved in the development of the thymus and other tissues derived from pharyngeal pouches. These results identify biallelic, loss-of-function mutations as the cause of a syndromic form of SCID due to altered thymus development.
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http://dx.doi.org/10.1126/sciimmunol.aax1036DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7189207PMC
February 2020

Confirmed efficacy of etoposide and dexamethasone in HLH treatment: long-term results of the cooperative HLH-2004 study.

Blood 2017 12 21;130(25):2728-2738. Epub 2017 Sep 21.

Childhood Cancer Research Unit, Department of Women's and Children's Health, Karolinska Institute, Stockholm, Sweden.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening hyperinflammatory syndrome comprising familial/genetic HLH (FHL) and secondary HLH. In the HLH-94 study, with an estimated 5-year probability of survival (pSu) of 54% (95% confidence interval, 48%-60%), systemic therapy included etoposide, dexamethasone, and, from week 9, cyclosporine A (CSA). Hematopoietic stem cell transplantation (HSCT) was indicated in patients with familial/genetic, relapsing, or severe/persistent disease. In HLH-2004, CSA was instead administered upfront, aiming to reduce pre-HSCT mortality and morbidity. From 2004 to 2011, 369 children aged <18 years fulfilled HLH-2004 inclusion criteria (5 of 8 diagnostic criteria, affected siblings, and/or molecular diagnosis in FHL-causative genes). At median follow-up of 5.2 years, 230 of 369 patients (62%) were alive (5-year pSu, 61%; 56%-67%). Five-year pSu in children with (n = 168) and without (n = 201) family history/genetically verified FHL was 59% (52%-67%) and 64% (57%-71%), respectively (familial occurrence [n = 47], 58% [45%-75%]). Comparing with historical data (HLH-94), using HLH-94 inclusion criteria, pre-HSCT mortality was nonsignificantly reduced from 27% to 19% ( = .064 adjusted for age and sex). Time from start of therapy to HSCT was shorter compared with HLH-94 (020 adjusted for age and sex) and reported neurological alterations at HSCT were 22% in HLH-94 and 17% in HLH-2004 (using HLH-94 inclusion criteria). Five-year pSu post-HSCT overall was 66% (verified FHL, 70% [63%-78%]). Additional analyses provided specific suggestions on potential pre-HSCT treatment improvements. HLH-2004 confirms that a majority of patients may be rescued by the etoposide/dexamethasone combination but intensification with CSA upfront, adding corticosteroids to intrathecal therapy, and reduced time to HSCT did not improve outcome significantly.
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http://dx.doi.org/10.1182/blood-2017-06-788349DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5785801PMC
December 2017

Cytokine Profile of Engraftment Syndrome in Pediatric Hematopoietic Stem Cell Transplant Recipients.

Biol Blood Marrow Transplant 2016 Apr 29;22(4):690-697. Epub 2015 Dec 29.

Division of Bone Marrow Transplant and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

The biology of engraftment syndrome is poorly understood, and the degree of overlap with acute graft-versus-host disease (GVHD) is unclear. To understand engraftment syndrome better, plasma cytokine profiles were evaluated in 56 pediatric allogeneic bone marrow transplant recipients before transplant, on the day of stem cell infusion, and weekly until day +100. Patients were divided into 4 groups: those with isolated engraftment syndrome (n = 8), acute GVHD (n = 12), both engraftment syndrome and acute GVHD (n = 4), and neither engraftment syndrome nor acute GVHD (n = 32). Engraftment syndrome was observed a median of 13.5 days (range, 10 to 28) after transplant, whereas acute GVHD was diagnosed a median of 55 days (range, 19 to 95) after transplant. Four patients developed both engraftment syndrome at a median of 10.5 days (range, 10 to 11) and acute GVHD at a median of 35 days (range, 23 to 56) after stem cell infusion. Median plasma levels of IL-1β, IL-6, IL-12, IL-4, and IL-13 were significantly elevated in patients with isolated engraftment syndrome when compared with isolated acute GVHD. A rise of proinflammatory cytokines (IL-1β, IL-6, and IL-12) was followed by surge in anti-inflammatory cytokines (IL-4 and IL-13) in patients with isolated engraftment syndrome. The observation of elevated IL-1β suggests that engraftment syndrome could be an inflammasome mediated phenomenon.
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http://dx.doi.org/10.1016/j.bbmt.2015.12.016DOI Listing
April 2016

Alemtuzumab levels impact acute GVHD, mixed chimerism, and lymphocyte recovery following alemtuzumab, fludarabine, and melphalan RIC HCT.

Blood 2016 Jan 7;127(4):503-12. Epub 2015 Dec 7.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital, Cincinnati, OH.

Reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) with alemtuzumab, fludarabine, and melphalan is an effective approach for patients with nonmalignant disorders. Mixed chimerism and graft-versus-host-disease (GVHD) remain limitations on success. We hypothesized that higher levels of alemtuzumab at day 0 would result in a low risk of acute GVHD, a higher risk of mixed chimerism, and delayed early lymphocyte recovery and that alemtuzumab level thresholds for increased risks of these outcomes would be definable. We collected data from 105 patients to examine the influence of peritransplant alemtuzumab levels on acute GVHD, mixed chimerism, and lymphocyte recovery. The cumulative incidences of initial grades I-IV, II-IV, and III-IV acute GVHD in patients with alemtuzumab levels ≤0.15 vs ≥0.16 μg/mL were 68% vs 18% (P < .0001), 47% vs 13% (P = .0002), and 32% vs 8%, respectively (P = .005). The cumulative incidence of mixed chimerism in patients with an alemtuzumab level ≤0.15 μg/mL was 21%, vs 42% with levels of 0.16 to 4.35 μg/mL, and 100% with levels >4.35 μg/mL (P = .003). Patients with alemtuzumab levels ≤0.15 or 0.16 to 0.56 μg/mL had higher lymphocyte counts at day +30 and higher T-cell counts at day +100 compared with patients with levels ≥0.57 μg/mL (all P < .05). We conclude that peritransplant alemtuzumab levels impact acute GVHD, mixed chimerism, and lymphocyte recovery following RIC HCT with alemtuzumab, fludarabine, and melphalan. Precision dosing trials are warranted. We recommend a day 0 therapeutic range of 0.2 to 0.4 μg/mL.
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http://dx.doi.org/10.1182/blood-2015-07-659672DOI Listing
January 2016

A challenging undertaking: Stem cell transplantation for immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome.

J Allergy Clin Immunol 2016 Mar 11;137(3):953-5.e4. Epub 2015 Nov 11.

Division of Bone Marrow Transplantation and Immune deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

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http://dx.doi.org/10.1016/j.jaci.2015.09.030DOI Listing
March 2016

Pathogenesis of Hemophagocytic Lymphohistiocytosis.

Hematol Oncol Clin North Am 2015 Oct 21;29(5):895-902. Epub 2015 Aug 21.

Immunodeficiency and Histiocytosis Program, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA. Electronic address:

Hemophagocytic Lymphohistiocytosis (HLH), an inherited life-threatening inflammatory disorder, has gained growing recognition not only in children but also increasingly in adults over the past 2 decades. HLH involves inborn defects in lymphocytes, which normally mediate control of infectious and inflammatory conditions within the immune system and in other tissues. In the context of inherited defects in cytotoxic cells and other immune cells, the disorder is classified as familial or primary HLH. Secondary HLH occurs in the settings of infections or underlying rheumatologic disorders. Secondary HLH also accompanies some lymphoid malignancies.
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http://dx.doi.org/10.1016/j.hoc.2015.06.007DOI Listing
October 2015

Accuracy of flow cytometric perforin screening for detecting patients with FHL due to PRF1 mutations.

Blood 2015 Oct;126(15):1858-60

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, OH.

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http://dx.doi.org/10.1182/blood-2015-06-648659DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4828082PMC
October 2015

Activated phosphoinositide 3-kinase δ syndrome in a patient with a former diagnosis of common variable immune deficiency, bronchiectasis, and lymphoproliferative disease.

Ann Allergy Asthma Immunol 2015 Nov 12;115(5):452-4. Epub 2015 Sep 12.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio. Electronic address:

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http://dx.doi.org/10.1016/j.anai.2015.08.009DOI Listing
November 2015

AUTOIMMUNE DISEASE. Patients with LRBA deficiency show CTLA4 loss and immune dysregulation responsive to abatacept therapy.

Science 2015 Jul;349(6246):436-40

Division of Bone Marrow Transplantation and Immune Deficiency, Department of Pediatrics, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Cincinnati, OH, USA. Division of Immunobiology, Department of Pediatrics, Cincinnati Children's Hospital Medical Center/ University of Cincinnati, Cincinnati, OH, USA.

Mutations in the LRBA gene (encoding the lipopolysaccharide-responsive and beige-like anchor protein) cause a syndrome of autoimmunity, lymphoproliferation, and humoral immune deficiency. The biological role of LRBA in immunologic disease is unknown. We found that patients with LRBA deficiency manifested a dramatic and sustained improvement in response to abatacept, a CTLA4 (cytotoxic T lymphocyte antigen-4)-immunoglobulin fusion drug. Clinical responses and homology of LRBA to proteins controlling intracellular trafficking led us to hypothesize that it regulates CTLA4, a potent inhibitory immune receptor. We found that LRBA colocalized with CTLA4 in endosomal vesicles and that LRBA deficiency or knockdown increased CTLA4 turnover, which resulted in reduced levels of CTLA4 protein in FoxP3(+) regulatory and activated conventional T cells. In LRBA-deficient cells, inhibition of lysosome degradation with chloroquine prevented CTLA4 loss. These findings elucidate a mechanism for CTLA4 trafficking and control of immune responses and suggest therapies for diseases involving the CTLA4 pathway.
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http://dx.doi.org/10.1126/science.aaa1663DOI Listing
July 2015

MicroRNA activation signature in patients with hemophagocytic lymphohistiocytosis and reversibility with disease-specific therapy.

J Allergy Clin Immunol 2016 Jan 17;137(1):309-312. Epub 2015 Jul 17.

Division of Bone Marrow Transplantation and Immune Deficiency, Blood and Cancer Research Institute, Cincinnati Children's Hospital Medical Center, University of Cincinnati, Faculty of Medicine, Cincinnati, Ohio.

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http://dx.doi.org/10.1016/j.jaci.2015.06.006DOI Listing
January 2016

Peripheral Blood CD38 Bright CD8+ Effector Memory T Cells Predict Acute Graft-versus-Host Disease.

Biol Blood Marrow Transplant 2015 Jul 13;21(7):1215-22. Epub 2015 Apr 13.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

Acute graft-versus-host disease (aGVHD) is mediated by allogeneic T cell responses. We hypothesized that increases of peripheral blood-activated CD8+ effector memory T (TEM) cells would be observed after hematopoietic stem cell transplantation (HSCT) before onset of aGVHD symptoms. Blood was collected twice weekly after HSCT for 7 weeks in 49 consecutive pediatric and adult HSCT recipients. Samples were incubated with fluorochrome-conjugated antibodies against CD45, CD3, CD8, CD38, CD45RA, and CCR7 and analyzed using flow cytometry. TEM cells were defined as CD3+ CD8+ CCR7- CD45RA(-) lymphocytes. CD38 expression was used as a marker of T cell activation. Patients were followed for 100 days for development of aGVHD. Twenty-three patients developed grade 1 to 4 aGVHD at a median of 37 days (range, 15 to 79 days) after HCST. Absolute CD38 bright CD8+ TEM of > 35 cells/μL predicted aGVHD at a median of 8 days (range, 1 to 34) before aGVHD onset with a sensitivity of 82.6% and specificity of 91.6%. The cumulative incidence of aGVHD was 90% in patients with absolute CD38 bright CD8+ TEM >35 cells/μL and 15% in patients without (P < .0001). Quantification of CD38 bright CD8+ TEM cells may predict aGVHD in children and young adult HSCT recipients.
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http://dx.doi.org/10.1016/j.bbmt.2015.04.010DOI Listing
July 2015

Experience with Alemtuzumab, Fludarabine, and Melphalan Reduced-Intensity Conditioning Hematopoietic Cell Transplantation in Patients with Nonmalignant Diseases Reveals Good Outcomes and That the Risk of Mixed Chimerism Depends on Underlying Disease, Stem Cell Source, and Alemtuzumab Regimen.

Biol Blood Marrow Transplant 2015 Aug 10;21(8):1460-70. Epub 2015 Apr 10.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

Alemtuzumab, fludarabine, and melphalan reduced-intensity conditioning (RIC) regimens are increasingly used for the hematopoietic cell transplantation (HCT) of pediatric and young adult patients with nonmalignant diseases. Early experience suggests that these regimens are associated with good survival but a high incidence of mixed chimerism, which we have previously shown to be influenced by the alemtuzumab schedule. We hypothesized that the underlying diagnosis and donor graft source would also affect the development of mixed chimerism and that the majority of patients would survive RIC HCT without graft loss. To examine this, we conducted a retrospective study of 206 patients with metabolic diseases, non-Fanconi anemia marrow failure disorders, and primary immune deficiencies who underwent 210 consecutive RIC HCT procedures at Cincinnati Children's Hospital. Ninety-seven percent of the patients engrafted. Mixed donor and recipient chimerism developed in 46% of patients. Patients with marrow failure had a low risk of mixed chimerism (hazard ratio [HR], .208; 95% confidence interval [CI], .061 to .709; P = .012). The risk of mixed chimerism was high in patients who received a cord blood graft (HR, 3.122; 95% CI, 1.236 to 7.888; P = .016). As expected, patients who received a proximal or higher dose per kilogram of alemtuzumab schedule also experienced higher rates of mixed chimerism (all HR > 2, all P < .05). At the time of last follow-up (median, 654 days; range, 13 to 3337), over 75% of patients had greater than 90% whole blood donor chimerism. A second transplantation was performed in 5% of patients. Three-year survival without retransplantation was 84% (95% CI, 71% to 98%) for patients who underwent transplantation with an HLA-matched sibling donor. Survival without retransplantation was negatively affected by lack of a matched related donor, increasing age, and development of grades III and IV acute graft-versus-host disease. We conclude that alemtuzumab, fludarabine, and melphalan RIC HCT offers good results for many patients and that the risk of developing mixed chimerism is influenced by underlying diagnosis, graft source, and alemtuzumab dosing.
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http://dx.doi.org/10.1016/j.bbmt.2015.04.009DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4603747PMC
August 2015

Haematopoietic stem cell transplantation for refractory Langerhans cell histiocytosis: outcome by intensity of conditioning.

Br J Haematol 2015 Jun 27;169(5):711-8. Epub 2015 Mar 27.

CIBMTR® (Center for International Blood and Marrow Transplant Research), Department of Medicine, Medical College of Wisconsin, Milwaukee, WI, USA.

Patients with Langerhans cell histiocytosis (LCH) refractory to conventional chemotherapy have a poor outcome. There are currently two promising treatment strategies for high-risk patients: the first involves the combination of 2-chlorodeoxyadenosine and cytarabine; the other approach is allogeneic haematopoietic stem cell transplantation (HSCT). Here we evaluated 87 patients with high-risk LCH who were transplanted between 1990 and 2013. Prior to the year 2000, most patients underwent HSCT following myeloablative conditioning (MAC): only 5 of 20 patients (25%) survived with a high rate (55%) of transplant-related mortality (TRM). After the year 2000 an increasing number of patients underwent HSCT with reduced intensity conditioning (RIC): 49/67 (73%) patients survived, however, the improved survival was not overtly achieved by the introduction of RIC regimens with similar 3-year probability of survival after MAC (77%) and RIC transplantation (71%). There was no significant difference in TRM by conditioning regimen intensity but relapse rates were higher after RIC compared to MAC regimens (28% vs. 8%, P = 0·02), although most patients relapsing after RIC transplantation could be salvaged with further chemotherapy. HSCT may be a curative approach in 3 out of 4 patients with high risk LCH refractory to chemotherapy: the optimal choice of HSCT conditioning remains uncertain.
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http://dx.doi.org/10.1111/bjh.13347DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4433436PMC
June 2015

Outcomes of donor lymphocyte infusion for treatment of mixed donor chimerism after a reduced-intensity preparative regimen for pediatric patients with nonmalignant diseases.

Biol Blood Marrow Transplant 2015 Feb 18;21(2):288-92. Epub 2014 Oct 18.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio. Electronic address:

Mixed donor chimerism is increasingly common in the pediatric hematopoietic stem cell transplantation (HSCT) setting because of the increased use of reduced-intensity preparative regimens for nonmalignant diseases. Donor lymphocyte infusion (DLI) is potentially useful in the treatment of mixed donor chimerism, but little are data available on the use of DLI in this setting. We conducted a retrospective review of 27 pediatric patients who received DLI for mixed donor chimerism between January 2006 and December 2010 after receiving a preparative regimen of alemtuzumab, fludarabine, and melphalan. Twenty-one patients (78%) were alive at a median of 35 months post-transplant. Seven patients (26%) sustained full donor chimerism after DLI only at a median of 35 months post-HSCT. Nine patients (33%) continued with mixed donor chimerism (median, 38% [range, 18% to 70%]) at a median of 37 months after DLI only. Five patients underwent unconditioned stem cell boosts or second conditioned transplants after no improvement in donor chimerism was seen following DLI. Donor source appeared to contribute to outcomes after DLI; patients with mismatched unrelated donors had earlier first decline in chimerism and timing of first DLI, a higher response rate to DLI, and an increased rate of graft-versus-host disease (GVHD). There was no response to DLI in patients with matched sibling donors. Ten patients, all with improvement in chimerism after DLI, developed acute GVHD after DLI, with 3 having grade III GVHD. Three patients developed chronic GVHD after DLI. These data illustrate the potential efficacy of DLI in the treatment of mixed donor chimerism after a reduced-intensity preparative regimen.
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http://dx.doi.org/10.1016/j.bbmt.2014.10.010DOI Listing
February 2015

Hematopoietic Stem Cell Transplantation for X-Linked Thrombocytopenia With Mutations in the WAS gene.

J Clin Immunol 2015 Jan 12;35(1):15-21. Epub 2014 Nov 12.

Department of Pediatrics, National Defense Medical College, Saitama, Japan.

X-linked thrombocytopenia (XLT) is a mild form of the Wiskott-Aldrich syndrome (WAS) caused by mutations in the WAS gene. A recent retrospective study of the clinical outcome and molecular basis of a large cohort of XLT patients demonstrated that although overall survival is excellent, event free survival is severely affected with conservative treatment. To answer the question whether hematopoietic stem cell transplantation (HSCT) offers a viable alternative therapeutic option in XLT, we retrospectively investigated the outcome of HSCT in a cohort of 24 XLT patients who received HSCT between 1990 and 2011 at 14 transplant centers in the United States, Italy, Germany, Canada, and Japan. The engraftment rate was 100% and the overall survival rate was 83.3%. Of the four non-survivors, 2 underwent splenectomy prior to HSCT and died of sepsis, and two of aspergillus infections associated with severe GVHD. In all but one patient, pretransplant complications were resolved by HSCT. Our data indicate that HSCT following myeloablative conditioning is curative and associated with acceptable risks as a treatment option for XLT.
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http://dx.doi.org/10.1007/s10875-014-0105-5DOI Listing
January 2015

A modified γ-retrovirus vector for X-linked severe combined immunodeficiency.

N Engl J Med 2014 Oct;371(15):1407-17

From the Departments of Biotherapy (S.H.-B.-A., J. Blondeau, L.C., F.T., M.C.) and Immunology and Pediatric Hematology (S.B., G.C., D.M., B.N., C.P., F.T., A.F.) and the Centre d'Étude des Déficits Immunitaires (C.P.), Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris (AP-HP), the Biotherapy Clinical Investigation Center, Groupe Hospitalier Universitaire Ouest, AP-HP, INSERM (S.H.-B.-A., J. Blondeau, L.C., F.T., M.C.), Unité de Technologies Chimiques et Biologiques pour la Santé, Centre National de la Recherche Scientifique, 8258-INSERM Unité 1022, Faculté des Sciences Pharmaceutiques et Biologiques, Université Paris Descartes (S.H.-B.-A.), Immunology Laboratory, Groupe Hospitalier Universitaire Paris-Sud, AP-HP, Le Kremlin-Bicêtre (S.H.-B.-A.), Imagine Institute, Paris Descartes-Sorbonne Paris Cité University (S.B., J. Blondeau, L.C., D.M., B.N., C.P., E.S., A.F., M.C.), INSERM Unités Mixtes de Recherche 1163, Laboratory of Human Lymphohematopoiesis (J. Blondeau, L.C., E.S., F.T., A.F., M.C.), Groupe Immunoscope, Immunology Department, Institut Pasteur (A.L.), and Collège de France (A.F.) - all in Paris; Division of Hematology-Oncology (S.-Y.P., H.B., D.G., C.E.H., G.H., L.E.L., W.B.L., D.A.W.) and Division of Immunology (L.D.N.), Boston Children's Hospital, Department of Pediatric Oncology, Dana-Farber Cancer Institute (S.-Y.P., D.G., L.E.L., W.B.L., D.A.W.), Harvard Medical School (S.-Y.P., M.A., L.E.L., W.B.L., J.R., L.E.S., A.T., L.D.N., D.A.W.), Center for Human Cell Therapy, Program in Cellular and Molecular Medicine, Boston Children's Hospital (M.A., J.R., L.E.S., A.T.), Division of Hematologic Malignancies, Dana-Farber Cancer Institute (J.R.), and the Manton Center for Orphan Disease Research (L.D.N.) - all in Boston; Great Ormond Street Hospital for Children NHS Foundation Trust (H.B.G., J.X.-B., A.J.T.) and Section of Molecular and Cellular Immunology, University College London Institute of Child Health (H.B.G., K.F.B., A.

Background: In previous clinical trials involving children with X-linked severe combined immunodeficiency (SCID-X1), a Moloney murine leukemia virus-based γ-retrovirus vector expressing interleukin-2 receptor γ-chain (γc) complementary DNA successfully restored immunity in most patients but resulted in vector-induced leukemia through enhancer-mediated mutagenesis in 25% of patients. We assessed the efficacy and safety of a self-inactivating retrovirus for the treatment of SCID-X1.

Methods: We enrolled nine boys with SCID-X1 in parallel trials in Europe and the United States to evaluate treatment with a self-inactivating (SIN) γ-retrovirus vector containing deletions in viral enhancer sequences expressing γc (SIN-γc).

Results: All patients received bone marrow-derived CD34+ cells transduced with the SIN-γc vector, without preparative conditioning. After 12.1 to 38.7 months of follow-up, eight of the nine children were still alive. One patient died from an overwhelming adenoviral infection before reconstitution with genetically modified T cells. Of the remaining eight patients, seven had recovery of peripheral-blood T cells that were functional and led to resolution of infections. The patients remained healthy thereafter. The kinetics of CD3+ T-cell recovery was not significantly different from that observed in previous trials. Assessment of insertion sites in peripheral blood from patients in the current trial as compared with those in previous trials revealed significantly less clustering of insertion sites within LMO2, MECOM, and other lymphoid proto-oncogenes in our patients.

Conclusions: This modified γ-retrovirus vector was found to retain efficacy in the treatment of SCID-X1. The long-term effect of this therapy on leukemogenesis remains unknown. (Funded by the National Institutes of Health and others; ClinicalTrials.gov numbers, NCT01410019, NCT01175239, and NCT01129544.).
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http://dx.doi.org/10.1056/NEJMoa1404588DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4274995PMC
October 2014

Transplantation outcomes for severe combined immunodeficiency, 2000-2009.

N Engl J Med 2014 Jul;371(5):434-46

The authors' affiliations are listed in the Appendix.

Background: The Primary Immune Deficiency Treatment Consortium was formed to analyze the results of hematopoietic-cell transplantation in children with severe combined immunodeficiency (SCID) and other primary immunodeficiencies. Factors associated with a good transplantation outcome need to be identified in order to design safer and more effective curative therapy, particularly for children with SCID diagnosed at birth.

Methods: We collected data retrospectively from 240 infants with SCID who had received transplants at 25 centers during a 10-year period (2000 through 2009).

Results: Survival at 5 years, freedom from immunoglobulin substitution, and CD3+ T-cell and IgA recovery were more likely among recipients of grafts from matched sibling donors than among recipients of grafts from alternative donors. However, the survival rate was high regardless of donor type among infants who received transplants at 3.5 months of age or younger (94%) and among older infants without prior infection (90%) or with infection that had resolved (82%). Among actively infected infants without a matched sibling donor, survival was best among recipients of haploidentical T-cell-depleted transplants in the absence of any pretransplantation conditioning. Among survivors, reduced-intensity or myeloablative pretransplantation conditioning was associated with an increased likelihood of a CD3+ T-cell count of more than 1000 per cubic millimeter, freedom from immunoglobulin substitution, and IgA recovery but did not significantly affect CD4+ T-cell recovery or recovery of phytohemagglutinin-induced T-cell proliferation. The genetic subtype of SCID affected the quality of CD3+ T-cell recovery but not survival.

Conclusions: Transplants from donors other than matched siblings were associated with excellent survival among infants with SCID identified before the onset of infection. All available graft sources are expected to lead to excellent survival among asymptomatic infants. (Funded by the National Institute of Allergy and Infectious Diseases and others.).
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http://dx.doi.org/10.1056/NEJMoa1401177DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4183064PMC
July 2014

Whole-exome sequencing reveals overlap between macrophage activation syndrome in systemic juvenile idiopathic arthritis and familial hemophagocytic lymphohistiocytosis.

Arthritis Rheumatol 2014 Dec;66(12):3486-95

Cincinnati Children's Hospital Medical Center and Cincinnati VA Medical Center, Cincinnati, Ohio.

Objective: Macrophage activation syndrome (MAS), a life-threatening complication of systemic juvenile idiopathic arthritis (JIA), resembles familial hemophagocytic lymphohistiocytosis (HLH), a constellation of autosomal-recessive immune disorders resulting from deficiency in cytolytic pathway proteins. We undertook this study to test our hypothesis that MAS predisposition in systemic JIA could be attributed to rare gene sequence variants affecting the cytotolytic pathway.

Methods: Whole-exome sequencing was used in 14 patients with systemic JIA and MAS and in their parents to identify protein-altering single-nucleotide polymorphisms/indels in known HLH-associated genes. To discover new candidate genes, the entire whole-exome sequencing data were filtered to identify protein-altering, rare recessive homozygous, compound heterozygous, and de novo variants with the potential to affect the cytolytic pathway.

Results: Heterozygous protein-altering rare variants in the known genes (LYST,MUNC13-4, and STXBP2) were found in 5 of 14 patients with systemic JIA and MAS (35.7%). This was in contrast to only 4 variants in 4 of 29 patients with systemic JIA without MAS (13.8%). Homozygosity and compound heterozygosity analysis applied to the entire whole-exome sequencing data in systemic JIA/MAS revealed 3 recessive pairs in 3 genes and compound heterozygotes in 73 genes. We also identified 20 heterozygous rare protein-altering variants that occurred in at least 2 patients. Many of the identified genes encoded proteins with a role in actin and microtubule reorganization and vesicle-mediated transport. "Cellular assembly and organization" was the top cellular function category based on Ingenuity Pathways Analysis (P < 3.10 × 10(-5) ).

Conclusion: Whole-exome sequencing performed in patients with systemic JIA and MAS identified rare protein-altering variants in known HLH-associated genes as well as in new candidate genes.
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http://dx.doi.org/10.1002/art.38793DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4321811PMC
December 2014

Bortezomib for refractory autoimmunity in pediatrics.

Biol Blood Marrow Transplant 2014 10 28;20(10):1654-9. Epub 2014 Jun 28.

Bone Marrow Transplant and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

Therapy of refractory autoimmunity remains challenging. In this study, we evaluated the therapeutic effect of bortezomib, a proteasome inhibitor, by targeting plasma cells in 7 patients (median age, 9.9 years). Four doses of bortezomib were administered at a dose of 1.3 mg/m(2) intravenously (n = 6) or subcutaneously (n = 1) every 72 hours. Bortezomib was administered at a median of 120 days from laboratory confirmation of autoantibodies. All patients had failed 2 or more standard therapies. Rituximab was administered on the first day if B cells were present, and all patients received plasmapheresis 2 hours before bortezomib administration. Six patients experienced resolution of cytopenias. Two of 6 patients experienced recurrence of cytopenias after initial response. Adverse effects include nausea (n = 1), thrombocytopenia (n = 2), Clostridium difficile colitis (n = 1)), febrile neutropenia (n = 1), and cellulitis at the subcutaneous injection site (n = 1). Our experience suggests that bortezomib may be beneficial in the treatment of refractory autoimmunity in children.
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http://dx.doi.org/10.1016/j.bbmt.2014.06.032DOI Listing
October 2014

Reduced-intensity conditioning hematopoietic cell transplantation is an effective treatment for patients with SLAM-associated protein deficiency/X-linked lymphoproliferative disease type 1.

Biol Blood Marrow Transplant 2014 Oct 9;20(10):1641-5. Epub 2014 Jun 9.

Division of Bone Marrow Transplantation and Immune Deficiency, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital, Cincinnati, Ohio.

X-linked lymphoproliferative disease type 1 (XLP1) is a rare immune deficiency caused by mutations in SH2D1A. Allogeneic hematopoietic cell transplantation (HCT) is often performed because of the morbidity and mortality associated with XLP1. There is limited experience using reduced-intensity conditioning (RIC) regimens for these patients. Here we report our 8-year single-center experience. Sixteen consecutive patients diagnosed with XLP1 underwent allogeneic HCT between 2006 and 2013 after a RIC regimen consisting of alemtuzumab, fludarabine, and melphalan. Patient phenotypes included hemophagocytic lymphohistiocytosis (HLH) after Epstein-Barr virus (n = 5) or human herpesvirus 6 (n = 1), macrophage activation syndrome (n = 1), interstitial pneumonitis and encephalitis (n = 1), B cell lymphoma (n = 8), and hypogammaglobulinemia (n = 2). One patient was asymptomatic. Fourteen of 16 patients received 8/8 HLA-matched unrelated or related bone marrow grafts, whereas 2 patients received mismatched unrelated grafts. Acute graft-versus-host disease (GVHD) prophylaxis consisted of methylprednisolone and cyclosporine in all but 1 patient, who additionally received methotrexate. All patients had hematopoietic recovery. There were no cases of hepatic veno-occlusive disease or pulmonary hemorrhage. One patient (6%) developed acute GVHD and later also developed chronic GVHD (6%). Five patients (31%) developed mixed chimerism. Only 1 patient with mixed chimerism (6%) experienced a decline of donor chimerism to less than 50% but returned to full donor chimerism after infusion of donor lymphocytes and a CD34(+) selected stem cell boost. Infectious complications were frequent, particularly viral reactivation. One-year survival estimated by Kaplan-Meier analysis was 80%, with long-term survival estimated at 71%. Survival was similar for patients with or without a history of HLH (86% versus 75%, respectively, P = .70). There were no occurrences of lymphoma or HLH after HCT. RIC HCT with alemtuzumab, fludarabine, and melphalan is an effective treatment for patients with XLP1, offering good survival rates regardless of prior disease manifestations, including HLH.
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http://dx.doi.org/10.1016/j.bbmt.2014.06.003DOI Listing
October 2014

Synergistic defects of different molecules in the cytotoxic pathway lead to clinical familial hemophagocytic lymphohistiocytosis.

Blood 2014 Aug 10;124(8):1331-4. Epub 2014 Jun 10.

Division of Bone Marrow Transplantation and Immune Deficiency, Cancer and Blood Diseases Institute, and.

Several molecules (LYST, AP3, RAB27A, STX11, STXBP2, MUNC13-4, and PRF1) have been associated with the function of cytotoxic lymphocytes. Biallelic defects in all of these molecules have been associated with familial hemophagocytic lymphohistiocytosis (FHL). We retrospectively reviewed the genetic and immunology test results from 2701 patients with a clinically suspected diagnosis of hemophagocytic lymphohistiocytosis and found 28 patients with single heterozygous mutations in 2 FHL-associated genes. Of these patients, 21 had mutations within PRF1 and a degranulation gene, and 7 were found to have mutations within 2 genes involved in the degranulation pathway. In patients with combination defects involving 2 genes in the degranulation pathway, CD107a degranulation was decreased, comparable to patients with biallelic mutations in one of the genes in the degranulation pathway. This suggests a potential digenic mode of inheritance of FHL as a result of a synergistic function effect within genes involved in cytotoxic lymphocyte degranulation.
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http://dx.doi.org/10.1182/blood-2014-05-573105DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4141517PMC
August 2014

Clinical flow cytometric screening of SAP and XIAP expression accurately identifies patients with SH2D1A and XIAP/BIRC4 mutations.

Cytometry B Clin Cytom 2014 Jul 19;86(4):263-71. Epub 2014 Feb 19.

Division of Bone Marrow Transplantation and Immune Deficiency, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.

Introduction: X-linked lymphoproliferative disease is caused by mutations in two genes, SH2D1A and XIAP/BIRC4. Flow cytometric methods have been developed to detect the gene products, SAP and XIAP. However, there is no literature describing the accuracy of flow cytometric screening performed in a clinical lab setting.

Methods: We reviewed the clinical flow cytometric testing results for 656 SAP and 586 XIAP samples tested during a 3-year period. Genetic testing was clinically performed as directed by the managing physician in 137 SAP (21%) and 115 XIAP (20%) samples. We included these samples for analyses of flow cytometric test accuracy.

Results: SH2D1A mutations were detected in 15/137 samples. SAP expression was low in 13/15 (sensitivity 87%, CI 61-97%). Of the 122 samples with normal sequencing, SAP was normal in 109 (specificity 89%, CI 82-94%). The positive predictive values (PPVs) and the negative predictive values (NPVs) were 50% and 98%, respectively. XIAP/BIRC4 mutations were detected in 19/115 samples. XIAP expression was low in 18/19 (sensitivity 95%, CI 73-100%). Of the 96 samples with normal sequencing, 59 had normal XIAP expression (specificity 61%, CI 51-71%). The PPVs and NPVs were 33% and 98%, respectively. Receiver-operating characteristic analysis was able to improve the specificity to 75%.

Conclusion: Clinical flow cytometric screening tests for SAP and XIAP deficiencies offer good sensitivity and specificity for detecting genetic mutations, and are characterized by high NPVs. We recommend these tests for patients suspected of having X-linked lymphoproliferative disease type 1 (XLP1) or XLP2.
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http://dx.doi.org/10.1002/cyto.b.21166DOI Listing
July 2014

Recommendations for live viral and bacterial vaccines in immunodeficient patients and their close contacts.

J Allergy Clin Immunol 2014 Apr 28;133(4):961-6. Epub 2014 Feb 28.

Johns Hopkins University School of Medicine, Baltimore, Md.

The present uncertainty of which live viral or bacterial vaccines can be given to immunodeficient patients and the growing neglect of societal adherence to routine immunizations has prompted the Medical Advisory Committee of the Immune Deficiency Foundation to issue recommendations based on published literature and the collective experience of the committee members. These recommendations address the concern for immunodeficient patients acquiring infections from healthy subjects who have not been immunized or who are shedding live vaccine-derived viral or bacterial organisms. Such transmission of infectious agents can occur within the hospital, clinic, or home or at any public gathering. Collectively, we define this type of transmission as close-contact spread of infectious disease that is particularly relevant in patients with impaired immunity who might have an infection when exposed to subjects carrying vaccine-preventable infectious diseases or who have recently received a live vaccine. Immunodeficient patients who have received therapeutic hematopoietic stem transplantation are also at risk during the time when immune reconstitution is incomplete or while they are receiving immunosuppressive agents to prevent or treat graft-versus-host disease. This review recommends the general education of what is known about vaccine-preventable or vaccine-derived diseases being spread to immunodeficient patients at risk for close-contact spread of infection and describes the relative risks for a child with severe immunodeficiency. The review also recommends a balance between the need to protect vulnerable subjects and their social needs to integrate into society, attend school, and benefit from peer education.
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http://dx.doi.org/10.1016/j.jaci.2013.11.043DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4009347PMC
April 2014

Clinical Flow Cytometric Screening of SAP and XIAP Expression Accurately Identifies Patients with SH2D1A and XIAP/BIRC4 Mutations.

Cytometry B Clin Cytom 2014 Feb 7. Epub 2014 Feb 7.

Division of Bone Marrow Transplantation and Immune Deficiency.

Introduction: X-linked lymphoproliferative disease is caused by mutations in 2 genes, SH2D1A and XIAP/BIRC4. Flow cytometric methods have been developed to detect the gene products, SAP and XIAP. However, there is no literature describing the accuracy of flow cytometric screening performed in a clinical lab setting.

Methods: We reviewed the clinical flow cytometric testing results for 656 SAP and 586 XIAP samples tested during a three year period. Genetic testing was clinically performed as directed by the managing physician in 137 SAP (21%) and 115 XIAP (20%) samples. We included these samples for analyses of flow cytometric test accuracy.

Results: SH2D1A mutations were detected in 15/137 samples. SAP expression was low in 13/15 (sensitivity 87%, CI 61-97%). Of the 122 samples with normal sequencing, SAP was normal in 109 (specificity 89%, CI 82-94%). The positive and negative predictive values were 50% and 98%, respectively. XIAP/BIRC4 mutations were detected in 19/115 samples. XIAP expression was low in 18/19 (sensitivity 95%, CI 73-100%). Of the 96 samples with normal sequencing, 59 had normal XIAP expression (specificity 61%, CI 51-71%). The positive and negative predictive values were 33% and 98%, respectively. Receiver operating characteristic analysis was able to improve the specificity to 75%.

Conclusion: Clinical flow cytometric screening tests for SAP and XIAP deficiencies offer good sensitivity and specificity for detecting genetic mutations, and are characterized by high negative predictive values. We recommend these tests for patients suspected of having XLP1 or XLP2. © 2014 Clinical Cytometry Society.
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http://dx.doi.org/10.1002/cytob.21166DOI Listing
February 2014

The 253-kb inversion and deep intronic mutations in UNC13D are present in North American patients with familial hemophagocytic lymphohistiocytosis 3.

Pediatr Blood Cancer 2014 Jun 28;61(6):1034-40. Epub 2014 Jan 28.

Division of Human Genetics, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio; Department of Pediatrics, University of Cincinnati School of Medicine, Cincinnati, Ohio.

Background: The mutations in UNC13D are responsible for familial hemophagocytic lymphohistiocytosis (FHL) type 3. A 253-kb inversion and two deep intronic mutations, c.118-308C > T and c.118-307G > A, in UNC13D were recently reported in European and Asian FHL3 patients. We sought to determine the prevalence of these three non-coding mutations in North American FHL patients and evaluate the significance of examining these new mutations in genetic testing.

Procedure: We performed DNA sequencing of UNC13D and targeted analysis of these three mutations in 1,709 North American patients with a suspected clinical diagnosis of hemophagocytic lymphohistiocytosis (HLH).

Results: The 253-kb inversion, intronic mutations c.118-308C > T and c.118-307G > A were found in 11, 15, and 4 patients, respectively, in which the genetic basis (bi-allelic mutations) explained 25 additional patients. Taken together with previously diagnosed FHL3 patients in our HLH patient registry, these three non-coding mutations were found in 31.6% (25/79) of the FHL3 patients. The 253-kb inversion, c.118-308C > T and c.118-307G > A accounted for 7.0%, 8.9%, and 1.3% of mutant alleles, respectively. Significantly, eight novel mutations in UNC13D are being reported in this study. To further evaluate the expression level of the newly reported intronic mutation c.118-307G > A, reverse transcription PCR and Western blot analysis revealed a significant reduction of both RNA and protein levels suggesting that the c.118-307G > A mutation affects transcription.

Conclusions: These specified non-coding mutations were found in a significant number of North American patients and inclusion of them in mutation analysis will improve the molecular diagnosis of FHL3.
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http://dx.doi.org/10.1002/pbc.24955DOI Listing
June 2014

The successful use of alemtuzumab for treatment of steroid-refractory acute graft-versus-host disease in pediatric patients.

Pediatr Transplant 2014 Feb 30;18(1):94-102. Epub 2013 Oct 30.

Division of Bone Marrow Transplantation and Immune Deficiency, Cancer and Blood Diseases Institute, Cincinnati Children's Hospital, Cincinnati, OH, USA.

SR-aGVHD remains a significant cause of morbidity and mortality in allogeneic HCT recipients. Alemtuzumab has been used with success in adult patients but has not been studied in the pediatric setting. To estimate the effectiveness of alemtuzumab for the treatment of SR-aGVHD in pediatric patients, we retrospectively reviewed the charts of 19 patients (median age 4 yr, range 0.5-28 years) with grades II (n = 3), III (n = 10), or IV (n = 6) SR-aGVHD who received alemtuzumab treatment. Patients received a median dose of 0.9 mg/kg alemtuzumab (range 0.3-2 mg/kg) divided over 2-6 days. Eighty-nine percent of patients received additional courses. A complete response, defined as GVHD of grade 0 at four wk following the first alemtuzumab course, was observed in nine patients (47%). A partial response, defined as an improvement in grade after four wk, was observed in five patients (26%). There was no response in five patients (26%). The overall response rate at four wk was 73%. Infectious complications included bacteremia (47%), presumed or documented fungal infections (21%), adenovirus viremia (52%), EBV viremia (36%), and CMV viremia (36%). We conclude that alemtuzumab is effective for SR-aGVHD in pediatric patients with a tolerable spectrum of complications.
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http://dx.doi.org/10.1111/petr.12183DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4167786PMC
February 2014

Downbeat nystagmus secondary to familial hemophagocytic lymphohistiocytosis.

J Neuroophthalmol 2014 Mar;34(1):57-60

Columbia University College of Physicians and Surgeons (CXC), New York, New York; Departments of Ophthalmology (FSS, JGO), Radiology (AL), and Pathology (TG); Columbia University Medical Center, New York Presbyterian Hospital, New York, New York; and Department of Clinical Immunology (AHF), Cincinnati Children's Hospital, University of Cincinnati, Cincinnati, Ohio.

Hemophagocytic lymphohistiocytosis is a rare autosomal recessive disorder characterized by severe inflammation induced by defective natural killer cell function, which triggers a state of highly stimulated but ineffective immune response. This disorder can affect multiple organ systems, and neurologic manifestations include irritability, seizures, impaired consciousness, meningismus, and cranial nerve palsies. We describe a unique case of hemophagocytic lymphohistiocytosis in which downbeat nystagmus developed due to cerebellar swelling with compression of the cervicomedullary junction.
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http://dx.doi.org/10.1097/WNO.0000000000000064DOI Listing
March 2014

Primary Immune Deficiency Treatment Consortium (PIDTC) report.

J Allergy Clin Immunol 2014 Feb 15;133(2):335-47. Epub 2013 Oct 15.

Department of Immunology, University of Toronto, Toronto, Ontario, Canada.

The Primary Immune Deficiency Treatment Consortium (PIDTC) is a network of 33 centers in North America that study the treatment of rare and severe primary immunodeficiency diseases. Current protocols address the natural history of patients treated for severe combined immunodeficiency (SCID), Wiskott-Aldrich syndrome, and chronic granulomatous disease through retrospective, prospective, and cross-sectional studies. The PIDTC additionally seeks to encourage training of junior investigators, establish partnerships with European and other International colleagues, work with patient advocacy groups to promote community awareness, and conduct pilot demonstration projects. Future goals include the conduct of prospective treatment studies to determine optimal therapies for primary immunodeficiency diseases. To date, the PIDTC has funded 2 pilot projects: newborn screening for SCID in Navajo Native Americans and B-cell reconstitution in patients with SCID after hematopoietic stem cell transplantation. Ten junior investigators have received grant awards. The PIDTC Annual Scientific Workshop has brought together consortium members, outside speakers, patient advocacy groups, and young investigators and trainees to report progress of the protocols and discuss common interests and goals, including new scientific developments and future directions of clinical research. Here we report the progress of the PIDTC to date, highlights of the first 2 PIDTC workshops, and consideration of future consortium objectives.
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http://dx.doi.org/10.1016/j.jaci.2013.07.052DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3960312PMC
February 2014

Sustained elevation of serum interleukin-18 and its association with hemophagocytic lymphohistiocytosis in XIAP deficiency.

Cytokine 2014 Jan 29;65(1):74-8. Epub 2013 Sep 29.

Department of Pediatrics, School of Medicine, Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan. Electronic address:

X-linked lymphoproliferative syndrome (XLP) is a rare primary immunodeficiency characterized by increased vulnerability to Epstein-Barr virus infection. XLP type 1 is caused by mutations in SH2D1A, whereas X-linked inhibitor of apoptosis (XIAP) encoded by XIAP/BIRC4 is mutated in XLP type 2. In XIAP deficiency, hemophagocytic lymphohistiocytosis (HLH) occurs more frequently and recurrence is common. However, the underlying mechanisms remain mostly unknown. We describe the characteristics of the cytokine profiles of serum samples from 10 XIAP-deficient patients. The concentration of interleukin (IL)-18 was strikingly elevated in the patients presented with HLH, and remained high after the recovery from HLH although levels of other pro-inflammatory cytokines approached the normal range. Longitudinal examination of two patients demonstrated marked exacerbation of IL-18 levels during every occasion of HLH. These findings may suggest the association between HLH susceptibility and high serum IL-18 levels in XIAP deficiency.
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http://dx.doi.org/10.1016/j.cyto.2013.09.007DOI Listing
January 2014