Person: Geha, Raif
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Geha
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Raif
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Geha, Raif
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Publication 14 Years after Discovery: Clinical Follow-up on 15 Patients with Inducible Co-Stimulator Deficiency(Frontiers Media S.A., 2017) Schepp, Johanna; Chou, Janet; Skrabl-Baumgartner, Andrea; Arkwright, Peter D.; Engelhardt, Karin R.; Hambleton, Sophie; Morio, Tomohiro; Röther, Ekkehard; Warnatz, Klaus; Geha, Raif; Grimbacher, BodoBackground: Inducible co-stimulator (ICOS) deficiency was the first monogenic defect reported to cause common variable immunodeficiency (CVID)-like disease in 2003. Since then, 16 patients have been reported worldwide with an increasing range of clinical phenotypes. Objective: We sought to compare the clinical and immunological phenotype and provide clinical follow-up and therapeutic approaches for treating ICOS-deficient patients. Methods: We describe the clinical and laboratory data of 15 patients with available clinical data. Previous publications and clinical assessment were used as data sources. Results: The observed ICOS gene mutations were all deletions leading to undetectable protein expression. The clinical phenotype of ICOS deficiency is much broader than initially anticipated and includes not only CVID-like disease but an increased susceptibility to viral and opportunistic infections, as well as cancer. Impaired B-cell development led to decreased memory B-cells in all patients, and hypogammaglobulinemia in all but one patient. Circulating CXCR5+ CD4+ follicular T-helper-cell numbers were also reduced in all patients. Treatment included immunoglobulin replacement, regular antibiotic prophylaxis, corticosteroids, and steroid-sparing agents. Three patients underwent hematopoietic stem cell transplantation; one of them died due to capillary leak syndrome on day 5 posttransplantation. Conclusion: The disease spectrum of ICOS deficiency is expanding from solely B-cell to combined B- and T-cell immunodeficiency, suggesting genetic and environmental modifiers. Genetic diagnosis is the only tool to distinguish ICOS deficiency from other immunological defects. Patients with antibody deficiency, autoimmunity, and combined immunodeficiency should be screened for ICOS mutations.Publication WASP-mediated regulation of anti-inflammatory macrophages is IL-10 dependent and is critical for intestinal homeostasis(Nature Publishing Group UK, 2018) Biswas, Amlan; Shouval, Dror S.; Griffith, Alexandra; Goettel, Jeremy; Field, Michael; Kang, Yu Hui; Konnikova, Liza; Janssen, Erin; Redhu, Naresh; Thrasher, Adrian J.; Chatila, Talal; Kuchroo, Vijay; Geha, Raif; Notarangelo, Luigi D.; Pai, Sung-Yun; Horwitz, Bruce; Snapper, ScottMutations in Wiskott–Aldrich syndrome protein (WASP) cause autoimmune sequelae including colitis. Yet, how WASP mediates mucosal homeostasis is not fully understood. Here we show that WASP-mediated regulation of anti-inflammatory macrophages is critical for mucosal homeostasis and immune tolerance. The generation and function of anti-inflammatory macrophages are defective in both human and mice in the absence of WASP. Expression of WASP specifically in macrophages, but not in dendritic cells, is critical for regulation of colitis development. Importantly, transfer of WT anti-inflammatory macrophages prevents the development of colitis. DOCK8-deficient macrophages phenocopy the altered macrophage properties associated with WASP deficiency. Mechanistically, we show that both WASP and DOCK8 regulates macrophage function by modulating IL-10-dependent STAT3 phosphorylation. Overall, our study indicates that anti-inflammatory macrophage function and mucosal immune tolerance require both WASP and DOCK8, and that IL-10 signalling modulates a WASP-DOCK8 complex.Publication Defective lymphoid organogenesis underlies the immune deficiency caused by a heterozygous S32I mutation in IκBα(The Rockefeller University Press, 2015) Mooster, Jana L.; Le Bras, Severine; Massaad, Michel; Jabara, Haifa; Yoon, Juhan; Galand, Claire; Heesters, Balthasar A.; Burton, Oliver T.; Mattoo, Hamid; Manis, John; Geha, RaifPatients with ectodermal dysplasia with immunodeficiency (ED-ID) caused by mutations in the inhibitor of NF-κB α (IκBα) are susceptible to severe recurrent infections, despite normal T and B cell numbers and intact in vitro lymphocyte function. Moreover, the outcome of hematopoietic stem cell transplantation (HSCT) in these patients is poor despite good engraftment. Mice heterozygous for the IκBα S32I mutation found in patients exhibited typical features of ED-ID. Strikingly, the mice lacked lymph nodes, Peyer’s patches, splenic marginal zones, and follicular dendritic cells and failed to develop contact hypersensitivity (CHS) or form germinal centers (GCs), all features not previously recognized in patients and typical of defective noncanonical NF-κB signaling. Lymphotoxin β receptor (LTβR)–driven induction of chemokines and adhesion molecules mediated by both canonical and noncanonical NF-κB pathways was impaired, and levels of p100 were markedly diminished in the mutant. IκBα mutant→Rag2−/−, but not WT→IκBα mutant, bone marrow chimeras formed proper lymphoid organs and developed CHS and GCs. Defective architectural cell function explains the immunodeficiency and poor outcome of HSCT in patients with IκBα deficiency and suggests that correction of this niche is critical for reconstituting their immune function.Publication Leucine-rich repeat containing 8A (LRRC8A) is essential for T lymphocyte development and function(The Rockefeller University Press, 2014) Kumar, Lalit; Chou, Janet; Yee, Christina; Borzutzky, Arturo; Vollmann, Elisabeth H.; von Andrian-Werburg, Ulrich; Park, Shin-Young; Hollander, Georg; Manis, John; Poliani, P. Luigi; Geha, RaifLrrc8a is a ubiquitously expressed gene that encodes a leucine-rich repeat (LRR)–containing protein detected at higher levels on the surface of thymocytes than on other immune cells. We generated Lrrc8a−/− mice to investigate the role of LRRC8A in lymphocyte development and function. Lrrc8a−/− mice had increased prenatal and postnatal mortality, growth retardation, and multiple tissue abnormalities. Lrrc8a−/− mice displayed a modest block in B cell development but intact intrinsic B cell function. In contrast, both Lrrc8a−/− mice and Lrrc8a−/−→Rag2−/− bone marrow chimeras exhibited a severe cell-intrinsic block in early thymic development, with decreased proliferation and increased apoptosis of thymocytes, and impaired peripheral T cell function. Thymic epithelial cells expressed an LRRC8A ligand that was critical for double-negative to double-positive thymocyte differentiation and survival in vitro. LRRC8A constitutively associated with the GRB2–GAB2 complex and lymphocyte-specific protein tyrosine kinase (LCK) in thymocytes. LRRC8A ligation activated AKT via the LCK–ZAP–70–GAB2–PI3K pathway, and AKT phosphorylation was markedly reduced in the thymus of Lrrc8a−/− mice. These findings reveal an essential role for LRRC8A in T cell development, survival, and function.Publication Leukotriene B4-Driven Neutrophil Recruitment to the Skin Is Essential for Allergic Skin Inflammation(Elsevier BV, 2012) Oyoshi, Michiko; He, Rui; Li, Yitang; Mondal, Subhanjan; Yoon, Juhan; Afshar, Roshi; Chen, Mei; Lee, David M.; Luo, Hongbo; Luster, Andrew; Cho, John S.; Miller, Lloyd S.; Larson, Allison; Murphy, George; Geha, RaifScratching triggers skin flares in atopic dermatitis. We demonstrate that scratching of human skin and tape stripping of mouse skin cause neutrophil influx. In mice, this influx was largely dependent on the generation of leukotriene B4 (LTB4) by neutrophils and their expression of the LTB4 receptor BLT1. Allergic skin inflammation in response to epicutaneous (EC) application of ovalbumin to tape-stripped skin was severely impaired in \(Ltb4r1^{−/−}\) mice and required expression of BLT1 on both T cells and non-T cells. Cotransfer of wild-type (WT) neutrophils, but not neutrophils deficient in BLT1 or the LTB4-synthesizing enzyme LTA4H, restored the ability of WT \(CD4^+\) effector T cells to transfer allergic skin inflammation to \(Ltb4r1^{−/−}\) recipients. Pharmacologic blockade of LTB4 synthesis inhibited allergic skin inflammation elicited by cutaneous antigen challenge in previously EC-sensitized mice. Our results demonstrate that a neutrophil-T cell axis reliant on LTB4-BLT1 interaction is required for allergic skin inflammation.Publication The LRRC8A Mediated “Swell Activated” Chloride Conductance Is Dispensable for Vacuolar Homeostasis in Neutrophils(Frontiers Media S.A., 2017) Behe, Philippe; Foote, Juliet R.; Levine, Adam P.; Platt, Craig; Chou, Janet; Benavides, Fernando; Geha, Raif; Segal, Anthony W.The dialysis of human and mouse neutrophils in patch clamp experiments in the conventional whole-cell mode induces the emergence of a chloride (Cl-) current that appeared to be primarily regulated by cytoplasmic ionic strength. The characteristics of this current resembled that of the classical, and ubiquitous volume-sensitive outwardly rectifying Cl- current: strong outward rectification, selectivity sequence of the Eisenman1 type, insensitivity to external pH and strong inhibition by tamoxifen, DCPIB and WW781. We show that this current is essentially supported by the leucine rich repeat containing 8 A (LRRC8A); the naturally occurring LRRC8A truncation mutant in ebo/ebo mice drastically reduced Cl- conductance in neutrophils. Remarkably, the residual component presents a distinct pharmacology, but appears equally potentiated by reduced ionic strength. We have investigated the role of the LRRC8A-supported current in the ionic homeostasis of the phagosomal compartment. The vacuolar pH, measured using SNARF-1 labeled Candida albicans, normally rises because of NADPH oxidase activity, and this elevation is blocked by certain Cl- channel inhibitors. However, the pH rise remains intact in neutrophils from the ebo/ebo mice which also demonstrate preserved phagocytic and respiratory burst capacities and normal-sized vacuoles. Thus, the LRRC8A-dependent conductance of neutrophils largely accounts for their “swell activated” Cl- current, but is not required for homeostasis of the phagosomal killing compartment.Publication Wiskott-Aldrich Syndrome Interacting Protein Deficiency Uncovers the Role of the Co-receptor CD19 as a Generic Hub for PI3 Kinase Signaling in B Cells(Cell Press, 2015) Keppler, Selina Jessica; Gasparrini, Francesca; Burbage, Marianne; Aggarwal, Shweta; Frederico, Bruno; Geha, Raif; Way, Michael; Bruckbauer, Andreas; Batista, Facundo D.Summary Humans with Wiskott-Aldrich syndrome display a progressive immunological disorder associated with compromised Wiskott-Aldrich Syndrome Interacting Protein (WIP) function. Mice deficient in WIP recapitulate such an immunodeficiency that has been attributed to T cell dysfunction; however, any contribution of B cells is as yet undefined. Here we have shown that WIP deficiency resulted in defects in B cell homing, chemotaxis, survival, and differentiation, ultimately leading to diminished germinal center formation and antibody production. Furthermore, in the absence of WIP, several receptors, namely the BCR, BAFFR, CXCR4, CXCR5, CD40, and TLR4, were impaired in promoting CD19 co-receptor activation and subsequent PI3 kinase (PI3K) signaling. The underlying mechanism was due to a distortion in the actin and tetraspanin networks that lead to altered CD19 cell surface dynamics. In conclusion, our findings suggest that, by regulating the cortical actin cytoskeleton, WIP influences the function of CD19 as a general hub for PI3K signaling.Publication A missense mutation in TFRC, encoding transferrin receptor 1, causes combined immunodeficiency(2015) Jabara, Haifa H.; Boyden, Steven E.; Chou, Janet; Ramesh, Narayanaswamy; Massaad, Michel; Benson, Halli; Bainter, Wayne; Fraulino, David; Rahimov, Fedik; Sieff, Colin; Liu, Zhi-Jian; Alshemmari, Salem H.; Al-Ramadi, Basel K.; Al-Dhekri, Hasan; Arnaout, Rand; Abu-Shukair, Mohammad; Vatsayan, Anant; Silver, Eli; Ahuja, Sanjay; Davies, E. Graham; Sola-Visner, Martha; Ohsumi, Toshiro; Andrews, Nancy C.; Notarangelo, Luigi; Fleming, Mark; Al-Herz, Waleed; Kunkel, Louis; Geha, RaifPatients with a combined immunodeficiency characterized by normal numbers, but impaired function, of T and B cells had a homozygous p.Tyr20His mutation in transferrin receptor 1 (TfR1), encoded by TFRC. The mutation disrupts the TfR1 internalization motif, resulting in defective receptor endocytosis and markedly increased TfR1 surface expression. Iron citrate rescued the lymphocyte defects and transduction of wild type, but not mutant, TfR1 rescued impaired transferrin uptake in patient fibroblasts. TfrcY20H/Y20H mice recapitulated the patients’ immunologic defects. Despite the critical role of TfR1 in erythrocyte development and function, the patients had only mild anemia and only slightly increased TfR1 expression in erythroid precursors. We show that STEAP3, a metalloreductase expressed in erythroblasts, associates with TfR1 and partially rescues transferrin uptake in patient fibroblasts, suggesting that STEAP3 may provide an accessory TfR1 endocytosis signal that spares the patients from severe anemia. These findings demonstrate the importance of TfR1 in adaptive immunity.Publication IL-23 induced in keratinocytes by endogenous TLR4 ligands polarizes dendritic cells to drive IL-22 responses to skin immunization(The Rockefeller University Press, 2016) Yoon, Juhan; Leyva-Castillo, Juan; Wang, Guoxing; Galand, Claire; Oyoshi, Michiko; Kumar, Lalit; Hoff, Sabine; He, Rui; Chervonsky, Alexander; Oppenheim, Joost J.; Kuchroo, Vijay; van den Brink, Marcel R.M.; Malefyt, Rene De Waal; Tessier, Philippe A.; Fuhlbrigge, Robert; Rosenstiel, Philip; Terhorst, Cox; Murphy, George; Geha, RaifAtopic dermatitis (AD) is a Th2-dominated inflammatory skin disease characterized by epidermal thickening. Serum levels of IL-22, a cytokine known to induce keratinocyte proliferation, are elevated in AD, and Th22 cells infiltrate AD skin lesions. We show that application of antigen to mouse skin subjected to tape stripping, a surrogate for scratching, induces an IL-22 response that drives epidermal hyperplasia and keratinocyte proliferation in a mouse model of skin inflammation that shares many features of AD. DC-derived IL-23 is known to act on CD4+ T cells to induce IL-22 production. However, the mechanisms that drive IL-23 production by skin DCs in response to cutaneous sensitization are not well understood. We demonstrate that IL-23 released by keratinocytes in response to endogenous TLR4 ligands causes skin DCs, which selectively express IL-23R, to up-regulate their endogenous IL-23 production and drive an IL-22 response in naive CD4+ T cells that mediates epidermal thickening. We also show that IL-23 is released in human skin after scratching and polarizes human skin DCs to drive an IL-22 response, supporting the utility of IL-23 and IL-22 blockade in AD.Publication DOCK8 Functions as an Adaptor that Links TLR–MyD88 Signaling to B Cell Activation(Nature Publishing Group, 2012) Rauter, Ingrid; Recher, Mike; Wakim, Rima; Dbaibo, Ghassan; Dasouki, Majed; Barlan, Isil; Baris, Safa; Kutukculer, Necil; Ochs, Hans; Plebani, Alessandro; Kanariou, Maria; Lefranc, Gerard; Reisli, Ismail; Fitzgerald, Katerine; Golenbock, Douglas; Keles, Sevgi; Ceja, Reuben; Jabara, Haifa Halim; McDonald, Douglas; Janssen, Erin; Massaad, Michel; Ramesh, Narayanaswamy; Borzutzky, Arturo; Benson, Halli Louise; Schneider, Lynda; Baxi, Sachin; Notarangelo, Luigi; Al-Herz, Waleed; Manis, John; Chatila, Talal; Geha, RaifDOCK8 and MyD88 have been implicated in serologic memory. Here we report antibody responses were impaired and \(CD27^+\) memory B cells were severely reduced in DOCK8-deficient patients. Toll-like receptor 9 (TLR9)- but not CD40-driven B cell proliferation and immunoglobulin production were severely reduced in DOCK8-deficient B cells. In contrast, TLR9-driven expression of AICDA, CD23 and CD86, and activation of NF-κB, p38 and Rac1 were intact. DOCK8 associated constitutively with MyD88 and the tyrosine kinase Pyk2 in normal B cells. Following TLR9 ligation, DOCK8 became tyrosine phosphorylated by Pyk2, bound the Src family kinase Lyn and linked TLR9 to a Src-Syk-STAT3 cascade essential for TLR9-driven B cell proliferation and differentiation. Thus, DOCK8 functions as an adaptor in a TLR9-MyD88 signaling pathway in B cells.