Person: ÖZEN, AHMET OĞUZHAN
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ÖZEN
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AHMET OĞUZHAN
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Publication Open Access Outcome of Hematopoietic Stem Cell Gene Therapy for Wiskott-Aldrich Syndrome(AMER SOC HEMATOLOGY, 2019-11-13) ÖZEN, AHMET OĞUZHAN; Labrosse, Roxane; Chu, Julia; Armant, Myriam; van der Spek, Jet; Miggelbrink, Alexandra; Fong, Johnson; Everett, John K.; Raymond, Hayley; Kessler, Lyanna; Dansereau, Colleen; Mackinnon, Brenda; Koo, Stephanie; Morris, Emily; London, Wendy B.; Ozen, Ahmet; Baris, Safa; Despotovic, Jenny M.; Forbes, Lisa; Saitoh, Akihiko; Takachi, Takayuki; King, Alejandra; Thi Mai Anh Thi Nguyen; Vy Do Uyen Vu; Bushman, Frederic D.; Galy, Anne; Notarangelo, Luigi; Williams, David A.; Pai, Sung-YunPublication Open Access Immediate adverse reactions to intravenous immunoglobulin in primary immune deficiencies: a single center experience(2020) ÖZEN, AHMET OĞUZHAN; Nain, Ercan; Kıykım, Ayça; Kasap, Nurhan Aruci; Barış, Safa; Özen, Ahmet; Aydıner, Elif KarakoçPublication Open Access Protein Expression in the Diagnosis of LRBA Deficiency by Flow Cytometer(BILIMSEL TIP YAYINEVI, 2017-11-17) ÖZEN, AHMET OĞUZHAN; Ogulur, Ismail; Kiykim, Ayca; Nain, Ercan; Somer, Ayper; Guven, Ayla; Baris, Safa; Ozen, Ahmet; Karakoc Aydiner, ElifObjective: Lipopolysaccharide-responsive beige-like anchor (LRBA) plays a role in cell surface expression of inhibitory cytotoxic T lymphocyte-associated protein-4 (CTLA-4) protein. Recently identified LRBA deficiency leads to immune deficiency and autoimmunity and is diagnosed by mutation analyses and protein expression. Herein, we quantified stimulated and unstimulated intracellular LRBA protein expression by flow cytometry in LRBA deficiency patients. Materials and Methods: Five LRBA deficient patients and seven healthy controls were evaluated. The LRBA expressions were assessed in peripheral-blood-mononuclear-cells in the presence or absence of phorbol-miristat-acetate and ionomycin stimulation. The difference in mean-fluorescence-intensity (Delta MFI) was calculated. Results: The differences in mean-fluorescence-intensity values of LRBA by flow cytometry were 24 +/- 9 for the healthy controls and 4.8 +/- 2.8 for the patients..MFIs were 20.8 for P3, 19 for P4 and 49.6 for healthy controls with stimulants and 4.8, 4.6 and 20.1 respectively without stimulants. Conclusion: As a rapid and widely available assay, flow cytometric assessment of intracellular LRBA expression has been found to be an effective and reliable method in the identification of LRBA deficiency.Publication Open Access Management of inborn errors of immunity in the genomic era(2022-03-01) ÖZEN, AHMET OĞUZHAN; Demir D. D., Asnaashari K., Rezaei N., Ozen A.Inborn errors of immunity are a group of rare diseases characterized by a wide variety of manifestations, including unusually severe infections, cancer susceptibility, and exaggerated inflammation that disrupts organ function. As of 2022, over 450 gene deficiencies have been classified under ten categories, where numbers are constantly increasing. The range of inborn errors of immunity varies considerably, from mild infections to serious multisystemic disease. Whereas patients with T cell defects are liable to a broad range of pathogens, selected inborn errors of immunity may predispose hosts merely to a narrow range of microorganisms. Dysregulated immune responses often cause autoimmune manifestations that may target any organ or lead to severe allergies. Therefore, presentation to any medical discipline is possible. Historically, inborn errors of immunity have been associated with short life expectancy and poor life quality, but intensive research into the field has revolutionized this assumption. Especially with the aid of translational investigations, our clinical practice has transformed from a predominantly phenotype-driven management into one that is reinforced by an etiology-driven therapy. This review summarizes the recent advances in molecularly targeted treatment approaches in various inborn errors of immunity conditions, with many success stories corroborating the power of genomic medicine. The principles of applications learned from these rare monogenic traits, in which the functional impact of the molecular pathways is clear-cut, may be instructive for developing basic concepts toward precision therapy of the common immune-mediated disorders, including autoimmunity, infectious diseases, and allergy, which affect mass populations.Publication Open Access Severe Early-Onset Combined Immunodeficiency due to Heterozygous Gain-of-Function Mutations in STAT1(SPRINGER/PLENUM PUBLISHERS, 2016-10) ÖZEN, AHMET OĞUZHAN; Baris, Safa; Alroqi, Fayhan; Kiykim, Ayca; Karakoc-Aydiner, Elif; Ogulur, Ismail; Ozen, Ahmet; Charbonnier, Louis-Marie; Bakir, Mustafa; Boztug, Kaan; Chatila, Talal A.; Barlan, Isil B.Loss and gain-of-function (GOF) mutations in human signal transducer and activator of transcription 1 (STAT1) lead to distinct phenotypes. Although recurrent infections are common to both types of STAT1 mutations, GOF mutations are distinguished by chronic mucocutaneous candidiasis and autoimmunity. However, the clinical spectra of STAT1 GOF mutations continue to expand. We here describe two patients with STAT1 GOF mutations presenting early in life with combined immunodeficiency (CID). Clinical data and laboratory findings including immunophenotyping, level of interferon (IFN)-gamma/IL-17(+) T cells, interferon-induced STAT1 phosphorylation, and JAK inhibitor assays were evaluated. Sequencing of STAT1 gene was performed by Sanger sequencer. Patient 1 (P1) had persistent oral candidiasis and cytomegalovirus (CMV) infection since 2 months of age and later developed cavitary lung lesions due to Mycobacterium tuberculosis. Patient 2 (P2) presented with oral candidiasis and recurrent pneumonia at 4 months of age and subsequently developed CMV pneumonitis. Both patients suffered heterozygous missense mutations in STAT1, leading to deleterious amino acid substitutions in the DNA binding domain (P1: c.1154C > T; p.T385M; P2. c.971G > T; p.C324F). Circulating CD4(+) T cells of both patients exhibited increased interferon-gamma and decreased IL-17 expression as compared to controls. They also exhibited increased IFN-beta and -gamma-induced STAT1 phosphorylation that was reversed upon treatment with the JAK kinase inhibitor ruxolitinib. STAT1 GOF mutations may present early in life with CID, consistent with the clinical heterogeneity of the disease. JAK kinase inhibitors may potentially be useful in some patients as adjunct therapy pending definitive treatment with bone marrow transplantation.Publication Open Access Mucus sialylation determines intestinal host-commensal homeostasis(2022-03-31) ÖZEN, AHMET OĞUZHAN; BARIŞ, SAFA; ERTEM ŞAHİNOĞLU, DENİZ; Yao Y., Kim G., Shafer S., Chen Z., Kubo S., Ji Y., Luo J., Yang W., Perner S. P., Kanellopoulou C., et al.Intestinal mucus forms the first line of defense against bacterial invasion while providing nutrition to support microbial symbiosis. How the host controls mucus barrier integrity and commensalism is unclear. We show that terminal sialylation of glycans on intestinal mucus by ST6GALNAC1 (ST6), the dominant sialyltransferase specifically expressed in goblet cells and induced by microbial pathogen-associated molecular patterns, is essential for mucus integrity and protecting against excessive bacterial proteolytic degradation. Glycoproteomic profiling and biochemical analysis of ST6 mutations identified in patients show that decreased sialylation causes defective mucus proteins and congenital inflammatory bowel disease (IBD). Mice harboring a patient ST6 mutation have compromised mucus barriers, dysbiosis, and susceptibility to intestinal inflammation. Based on our understanding of the ST6 regulatory network, we show that treatment with sialylated mucin or a Foxo3 inhibitor can ameliorate IBD.Publication Open Access A boy with a novel homozygous ZAP70 mutation presenting with a dermatological phenotype and postnatal decrease in CD8(+) T cells(2022-03-01) AYDINER, ELİF; ÖZEN, AHMET OĞUZHAN; BARIŞ, SAFA; Babayeva R., Mongellaz C., Karakus I. S., Cansever M., Bilgic Eltan S., Catak M. C., Bulutoglu A., Kendir Demirkol Y., Eser M., Karakoc-Aydiner E., et al.Patients with deficiency of zeta-chain-associated protein kinase 70 (ZAP-70) protein generally present as combined immunodeficiency (CID) with severe recurrent infections and dermatological findings during the first years of life. They also suffer from diarrhea, mainly resulting from viral agents, lymphoproliferation, and autoimmunity (autoimmune cytopenia, bullous pemphigoid, nephrotic syndrome, and adrenal insufficiency). The most striking immunological findings are severely decreased CD3+CD8+ T-cell counts with decreased proliferation. The current definitive treatment of ZAP-70 deficiency is hematopoietic stem cell transplantation (HSCT).1 To date, 52 patients with biallelic mutations in the ZAP70 gene have been described in the literature.1,2 Herein, we report a patient with a novel missense mutation in the ZAP70 who presented with atypical skin lesions and a rapid decrease in CD8+ T-cell counts on immunological evaluations between 6 and 9 months of age. Despite undetectable ZAP-70 protein, the patient did not present severe infections in the first year of life. This description expands the spectrum of disease caused by mutations in thePublication Open Access Long-term follow-up of IPEX syndrome patients after different therapeutic strategies: An international multicenter retrospective study(MOSBY-ELSEVIER, 2018-03) ÖZEN, AHMET OĞUZHAN; Barzaghi, Federica; Hernandez, Laura Cristina Amaya; Neven, Benedicte; Ricci, Silvia; Kucuk, Zeynep Yesim; Bleesing, Jack J.; Nademi, Zohreh; Slatter, Mary Anne; Ulloa, Erlinda Rose; Shcherbina, Anna; Roppelt, Anna; Worth, Austen; Silva, Juliana; Aiuti, Alessandro; Murguia-Favela, Luis; Speckmann, Carsten; Carneiro-Sampaio, Magda; Fernandes, Juliana Folloni; Baris, Safa; Ozen, Ahmet; Karakoc-Aydiner, Elif; Kiykim, Ayca; Schulz, Ansgar; Steinmann, Sandra; Notarangelo, Lucia Dora; Gambineri, Eleonora; Lionetti, Paolo; Shearer, William Thomas; Forbes, Lisa R.; Martinez, Caridad; Moshous, Despina; Blanche, Stephane; Fisher, Alain; Ruemmele, Frank M.; Tissandier, Come; Ouachee-Chardin, Marie; Rieux-Laucat, Frederic; Cavazzana, Marina; Qasim, Waseem; Lucarelli, Barbarella; Albert, Michael H.; Kobayashi, Ichiro; Alonso, Laura; De Heredia, Cristina Diaz; Kanegane, Hirokazu; Lawitschka, Anita; Seo, Jong Jin; Gonzalez-Vicent, Marta; Diaz, Miguel Angel; Goyal, Rakesh Kumar; Sauer, Martin G.; Yesilipek, Akif; Kim, Minsoo; Yilmaz-Demirdag, Yesim; Bhatia, Monica; Khlevner, Julie; Padilla, Erick J. Richmond; Martino, Silvana; Montin, Davide; Neth, Olaf; Molinos-Quintana, Agueda; Valverde-Fernandez, Justo; Broides, Arnon; Pinsk, Vered; Ballauf, Antje; Haerynck, Filomeen; Bordon, Victoria; Dhooge, Catharina; Garcia-Lloret, Maria Laura; Bredius, Robbert G.; Kalwak, Krzysztof; Haddad, Elie; Seidel, Markus Gerhard; Duckers, Gregor; Pai, Sung-Yun; Dvorak, Christopher C.; Ehl, Stephan; Locatelli, Franco; Goldman, Frederick; Gennery, Andrew Richard; Cowan, Mort J.; Roncarolo, Maria-Grazia; Bacchetta, RosaBackground: Immunodysregulation polyendocrinopathy enteropathy x-linked(IPEX) syndrome is a monogenic autoimmune disease caused by FOXP3 mutations. Because it is a rare disease, the natural history and response to treatments, including allogeneic hematopoietic stem cell transplantation (HSCT) and immunosuppression (IS), have not been thoroughly examined. Objective: This analysis sought to evaluate disease onset, progression, and long-term outcome of the 2 main treatments in long-term IPEX survivors. Methods: Clinical histories of 96 patients with a genetically proven IPEX syndrome were collected from 38 institutions worldwide and retrospectively analyzed. To investigate possible factors suitable to predict the outcome, an organ involvement (OI) scoring system was developed. Results: We confirm neonatal onset with enteropathy, type 1 diabetes, and eczema. In addition, we found less common manifestations in delayed onset patients or during disease evolution. There is no correlation between the site of mutation and the disease course or outcome, and the same genotype can present with variable phenotypes. HSCT patients (n = 58) had a median follow-up of 2.7 years (range, 1 week-15 years). Patients receiving chronic IS (n 5 34) had a median follow-up of 4 years (range, 2 months-25 years). The overall survival after HSCT was 73.2% (95% CI, 59.4-83.0) and after IS was 65.1% (95% CI, 62.8-95.8). The pretreatment OI score was the only significant predictor of overall survival after transplant (P = .035) but not under IS. Conclusions: Patients receiving chronic IS were hampered by disease recurrence or complications, impacting long-term.disease-free survival. When performed in patients with a low OI score, HSCT resulted in disease resolution with better quality of life, independent of age, donor source, or conditioning regimen.Publication Open Access The Diagnostic Value of Flow Cytometry in DOCK8 Deficiency(TURKISH SOC IMMUNOLOGY, 2019) ÖZEN, AHMET OĞUZHAN; Ogulur, Ismail; Kiykim, Ayca; Nain, Ercan; Kasap, Nurhan; Akgun, Gamze; Karakoc-Aydiner, Elif; Ozen, Ahmet; Baris, SafaIntroduction: DOCK8 deficiency is a combined immunodeficiency with severe eczema, food allergy and autoimmunity. Early diagnosis is important for the treatment of patients. In this study, diagnostic value of flow cytometric detection of DOCK8 protein expression was evaluated in patients with DOCK8 deficiency. Material and Methods: Seven patients with DOCK8 deficiency and 20 healthy controls were enrolled in the study. Peripheral blood mononuclear cells (PBMCs) were isolated from patients and healthy controls, and DOCK8 protein expressions were detected. The data were analyzed as raw mean fluorescein intensity (MFI) and difference in MFI (Delta MFI) between cells stained in patients and healthy controls with and-DOCK8 antibody and isotype control. As the experiments were done on different days, the Delta MPI values obtained were normalized according to the current healthy control values and percent values were calculated. Results: The median age of DOCK8 patients was 12 years (8-15). Six of the patients have large deletions and 1 has a missense mutation in DOCK8 gene. Raw MFI values (p=0.0008) and normalized Delta MFI-percent values (p<0.0001) were significantly lower in DOCK8 patients compared to healthy controls. The patient with missense mutation had a raw MFI value close to the control (patient MFI: 23.70, control MFI: 35.50). Median of raw MFI was 4.95 (3.65-5.67) in patients and 26.2 (21.6-32.1) in healthy controls. Conclusion: Flow cytometric detection of DOCK8 protein is very important for the diagnosis of DOCK8 deficiency since the deletion mutations cause almost complete loss of DOCK8 protein expression, while patients with missense mutations could have nearly normal levels of protein, and this can lead to the underestimation of the diagnosis. Therefore, flow cytometric detection is an adjunct method for the diagnosis of DOCK8 disease, and genetic analysis should be offered to all suspicious cases.Publication Open Access A recessive form of hyper-IgE syndrome by disruption of ZNF341-dependent STAT3 transcription and activity(AMER ASSOC ADVANCEMENT SCIENCE, 2018-06-08) ÖZEN, AHMET OĞUZHAN; Beziat, Vivien; Li, Juan; Lin, Jian-Xin; Ma, Cindy S.; Li, Peng; Bousfiha, Aziz; Pellier, Isabelle; Zoghi, Samaneh; Baris, Safa; Keles, Sevgi; Gray, Paul; Du, Ning; Wang, Yi; Zerbib, Yoann; Levy, Romain; Leclercq, Thibaut; About, Fredegonde; Lim, Ai Ing; Rao, Geetha; Payne, Kathryn; Pelham, Simon J.; Avery, Danielle T.; Deenick, Elissa K.; Pillay, Bethany; Chou, Janet; Guery, Romain; Belkadi, Aziz; Guerin, Antoine; Migaud, Melanie; Rattina, Vimel; Ailal, Fatima; Benhsaien, Ibtihal; Bouaziz, Matthieu; Habib, Tanwir; Chaussabel, Damien; Marr, Nico; El-Benna, Jamel; Grimbacher, Bodo; Wargon, Orli; Bustamante, Jacinta; Boisson, Bertrand; Mueller-Fleckenstein, Ingrid; Fleckenstein, Bernhard; Chandesris, Marie-Olivia; Titeux, Matthias; Fraitag, Sylvie; Alyanakian, Marie-Alexandra; Leruez-Ville, Marianne; Picard, Capucine; Meyts, Isabelle; Di Santo, James P.; Hovnanian, Alain; Somer, Ayper; Ozen, Ahmet; Rezaei, Nima; Chatila, Talal A.; Abel, Laurent; Leonard, Warren J.; Tangye, Stuart G.; Puel, Anne; Casanova, Jean-LaurentHeterozygosity for human signal transducer and activator of transcription 3 (STAT3) dominant-negative (DN) mutations underlies an autosomal dominant form of hyper-immunoglobulin E syndrome (HIES). We describe patients with an autosomal recessive form of HIES due to loss-of-function mutations of a previously uncharacterized gene, ZNF341. ZNF341 is a transcription factor that resides in the nucleus, where it binds a specific DNA motif present in various genes, including the STAT3 promoter. The patients' cells have low basal levels of STAT3 mRNA and protein. The autoinduction of STAT3 production, activation, and function by STAT3-activating cytokines is strongly impaired. Like patients with STAT3 DN mutations, ZNF341-deficient patients lack T helper 17 (T(H)17) cells, have an excess of T(H)2 cells, and have low memory B cells due to the tight dependence of STAT3 activity on ZNF341 in lymphocytes. Their milder extra-hematopoietic manifestations and stronger inflammatory responses reflect the lower ZNF341 dependence of STAT3 activity in other cell types. Human ZNF341 is essential for the STAT3 transcription-dependent autoinduction and sustained activity of STAT3.