Expanding the Clinical and Genetic Spectrum of Human CD40L Deficiency: The Occurrence of Paracoccidioidomycosis and Other Unusual Infections in Brazilian Patients

CD40 ligand (CD40L) deficiency or X-linked hyper-IgM syndrome (X-HIGM) is a well-described primary immunodeficiency in which Pneumocystis jiroveci pneumonia is a common clinical feature. We have identified an unusual high incidence of fungal infections and other not yet described infections in a cohort of 11 X-HIGM patients from nine unrelated Brazilian families. Among these, we describe the first case of paracoccidioidomycosis (PCM) in X-HIGM. The molecular genetic analysis of CD40L was performed by gene sequencing and evaluation of CD40L protein expression. Nine of these 11 patients (82%) had fungal infections. These included fungal species common to CD40L deficiency (P. jiroveci and Candida albicans) as well as Paracoccidioides brasiliensis. One patient presented with PCM at age 11 years and is now doing well at 18 years of age. Additionally, one patient presented with a simultaneous infection with Klebsiella and Acinetobacter, and one with condyloma caused by human papilloma virus. Molecular analysis revealed four previously described CD40L mutations, two novel missense mutations (c.433 T>G and c.476 G>C) resulting in the absence of CD40L protein expression by activated CD4(+) cells and one novel insertion (c.484_485insAA) within the TNFH domain leading to a frame shift and premature stop codon. These observations demonstrated that the susceptibility to fungal infections in X-HIGM extends beyond those typically associated with X-HIGM (P. jiroveci and C. albicans) and that these patients need to be monitored for those pathogens.FAPESP [2008/06635-0, 2008/55700-9]FAPESPCNPqCNPqJeffrey Modell FoundationJeffrey Modell Foundatio

Dendritic cells from X-linked hyper-IgM patients present impaired responses to Candida albicans and Paracoccidioides brasiliensis

Background: Patients with X-linked hyper-IgM syndrome (X-HIGM) due to CD40 ligand (CD40L) mutations are susceptible to fungal pathogens; however, the underlying susceptibility mechanisms remain poorly understood. Objective: To determine whether monocyte-derived dendritic cells (DCs) from patients with X-HIGM exhibit normal responses to fungal pathogens. Methods: DCs from patients and controls were evaluated for the expression of costimulatory (CD80 and CD86) and MHC class II molecules and for their ability to produce IL-12 and IL-10 in response to Candida albicans and Paracoccidioides brasiliensis. We also evaluated the ability of C albicans- and P brasiliensis-pulsed mature DCs to induce autologous T-cell proliferation, generation of T helper (T-H) 17 cells, and production of IFN-gamma, TGF-beta, IL-4, IL-5, and IL-17. Results: Immature DCs from patients with X-HIGM showed reduced expression of CD80, CD86, and HLA-DR, which could be reversed by exogenous trimeric soluble CD40L. Most important, mature DCs from patients with X-HIGM differentiated by coculturing DCs with fungi secreted minimal amounts of IL-12 but substantial amounts of IL-10 compared with mature DCs from normal individuals. Coculture of mature DCs from X-HIGM patients with autologous T cells led to low IFN-g production, whereas IL-4 and IL-5 production was increased. T-cell proliferation and IL-17 secretion were normal. Finally, in vitro incubation with soluble CD40L reversed the decreased IL-12 production and the skewed T-H(2) pattern response. Conclusion: Absence of CD40L during monocyte/DC differentiation leads to functional DC abnormalities, which may contribute to the susceptibility to fungal infections in patients with X-HIGM. (J Allergy Clin Immunol 2012; 129: 778-86.)FAPESPFAPESP [2008/06635-0, 2008/55700-9, 2009/54599-5]CNPqCNPqJeffrey Modell FoundationJeffrey Modell Foundatio

First Report of the Hyper-IgM Syndrome Registry of the Latin American Society for Immunodeficiencies: Novel Mutations, Unique Infections, and Outcomes

Hyper-IgM (HIGM) syndrome is a heterogeneous group of disorders characterized by normal or elevated serum IgM levels associated with absent or decreased IgG, IgA and IgE. Here we summarize data from the HIGM syndrome Registry of the Latin American Society for Immunodeficiencies (LASID). of the 58 patients from 51 families reported to the registry with the clinical phenotype of HIGM syndrome, molecular defects were identified in 37 patients thus far. We retrospectively analyzed the clinical, immunological and molecular data from these 37 patients. CD40 ligand (CD40L) deficiency was found in 35 patients from 25 families and activation-induced cytidine deaminase (AID) deficiency in 2 unrelated patients. Five previously unreported mutations were identified in the CD40L gene (CD40LG). Respiratory tract infections, mainly pneumonia, were the most frequent clinical manifestation. Previously undescribed fungal and opportunistic infections were observed in CD40L-deficient patients but not in the two patients with AID deficiency. These include the first cases of pneumonia caused by Mycoplasma pneumoniae, Serratia marcescens or Aspergillus sp. and diarrhea caused by Microsporidium sp. or Isospora belli. Except for four CD40L-deficient patients who died from complications of presumptive central nervous system infections or sepsis, all patients reported in this study are alive. Four CD40L-deficient patients underwent successful bone marrow transplantation. This report characterizes the clinical and genetic spectrum of HIGM syndrome in Latin America and expands the understanding of the genotype and phenotype of this syndrome in tropical areas.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Jeffrey Modell FoundationLatin American Advisory Board on Primary Immunodeficiencies initiativeUniv São Paulo, Inst Biomed Sci, Dept Immunol, BR-05508000 São Paulo, BrazilCtr Invest & Estudios, Dept Biomed Mol, Mexico City, DF, MexicoDr Ricardo Gutierrez Childrens Hosp, Buenos Aires, DF, ArgentinaHosp Nacl Ninos Dr Carlos Saenz Herrera, San Jose, Costa RicaPediat Allergy & Immunol Clin, Caxias Do Sul, RS, BrazilAlbert Sabin Hosp, Fortaleza, Ceara, BrazilHosp Base Dist Fed, Brasilia, DF, BrazilIntegrated Ctr Pediat Specialties, Curitiba, PR, BrazilHosp Ninos VJ Vilela, Rosario, ArgentinaHosp Ninos Luis Calvo Mackenna, Santiago, ChileUniv Fed Parana, Dept Pediat, BR-80060000 Curitiba, Parana, BrazilUniv Estadual Campinas, Sch Med, Dept Pediat, Campinas, SP, BrazilConceicao Childrens Hosp, Dept Pediat, Div Allergy & Immunol, Porto Alegre, RS, BrazilChildrens Hosp Lucidio Portela, Teresina, PI, BrazilPontificia Univ Catolica Chile, Div Pediat, Santiago, ChileUniv Estadual Campinas, Sch Med, Dept Med, Campinas, SP, BrazilUniv São Paulo, Ribeirao Preto Med Sch, BR-14049 Ribeirao Preto, SP, BrazilHosp Nacl Edgardo Rebagliati Martins Alergia & In, Lima, PeruUniv Fed Rio de Janeiro, Sch Med, Dept Pediat, Rio de Janeiro, BrazilInst Nacl Pediat, Unidad Invest Inmunodeficiencias, Mexico City, DF, MexicoIMSS, Unidad Med Alta Especialidad 25, Monterrey, Nuevo Leon, MexicoClin Montefiori, Unidad Inmunol, Lima, PeruUNAL, Univ Hosp, Monterrey, Nuevo Leon, MexicoFac Med ABC, Santo Andre, SP, BrazilChildrens Hosp, Dept Pediat, New Orleans, LA USAHop Necker Enfants Malad, INSERM, Unite U768, Paris, FranceUniv Washington, Sch Med, Dept Pediat, Seattle, WA 98195 USASeattle Childrens Res Inst, Seattle, WA USAUniversidade Federal de São Paulo, Dept Pediat, Div Allergy Immunol & Rheumatol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Pediat, Div Allergy Immunol & Rheumatol, São Paulo, BrazilFAPESP: 2012/50515-4FAPESP: 2006/57643-7FAPESP: 2012/51745-3Web of Scienc