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ÖĞÜLÜR, İSMAİL

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ÖĞÜLÜR

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İSMAİL

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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, Elif
Objective: 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.
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.
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, Safa
Introduction: 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.
Open Access
Dysregulation of the epithelial barrier by environmental and other exogenous factors
(WILEY, 2021-12) ÖĞÜLÜR, İSMAİL; Mitamura, Yasutaka; Ogulur, Ismail; Pat, Yagiz; Rinaldi, Arturo O.; Ardicli, Ozge; Cevhertas, Lacin; Brueggen, Marie-Charlotte; Traidl-Hoffmann, Claudia; Akdis, Mubeccel; Akdis, Cezmi A.
The epithelial barrier hypothesis proposes that the exposure to various epithelial barrier-damaging agents linked to industrialization and urbanization underlies the increase in allergic diseases. The epithelial barrier constitutes the first line of physical, chemical, and immunological defense against environmental factors. Recent reports have shown that industrial products disrupt the epithelial barriers. Innate and adaptive immune responses play an important role in epithelial barrier damage. In addition, recent studies suggest that epithelial barrier dysfunction plays an essential role in the pathogenesis of the atopic march by allergen sensitization through the transcutaneous route. It is evident that external factors interact with the immune system, triggering a cascade of complex reactions that damage the epithelial barrier. Epigenetic and microbiome changes modulate the integrity of the epithelial barrier. Robust and simple measurements of the skin barrier dysfunction at the point-of-care are of significant value as a biomarker, as recently reported using electrical impedance spectroscopy to directly measure barrier defects. Understanding epithelial barrier dysfunction and its mechanism is key to developing novel strategies for the prevention and treatment of allergic diseases. The aim of this review is to summarize recent studies on the pathophysiological mechanisms triggered by environmental factors that contribute to the dysregulation of epithelial barrier function.
Open Access
Differentiation of bronchial epithelial spheroids in the presence of IL-13 recapitulates characteristic features of asthmatic airway epithelia
(2022-07-01) ÖĞÜLÜR, İSMAİL; Pat Y., Ruckert B., Ogulur I., Yazici D., Perez-Diego M., Kucukkase O. C., Li M., Akdis C. A.
Open Access
Diagnostic Usage of Intracellular Protein Staining by Flow Cytometer in Primary Immune Deficiencies; Marmara Experience
(BILIMSEL TIP YAYINEVI, 2018-01-10) ÖZEN, AHMET OĞUZHAN; Ogulur, Ismail; Baris, Safa; Ozen, Ahmet; Nain, Ercan; Kiykim, Ayca; Karakoc-Aydiner, Elif
Objective: The aim of our study was the optimization and standardization of intracellular dedicator of cytokinesis 8 (DOCK8), LPS-responsive beige-like anchor protein (LRBA), SH2D1A/SLAM-ssociated protein (SAP) and X-linked inhibitor of apoptosis protein (XIAP) protein expressions in healthy controls with a single flow cytometer protocol and to concomitantly evaluate the possible use of this method for diagnosis. Materials and Methods: Peripheral blood mononuclear cells were isolated from heparinized blood samples. Protein expressions were analyzed as mean fluorescein intensity difference (Delta MFI) according to the isotype. Results: Delta MFI values obtained by DOCK8 antibody staining were 21.3 +/- 4 in CD3+ T cells and 25 +/- 3.3 in CD20+ T cells in healthy controls. These values in patients with DOCK8 deficiency were either very low or completely absent. Delta MFI values obtained by LRBA protein antibody staining were 36 +/- 7.7 in healthy controls, while they were at the very low levels of 5.9 +/- 1.8 in the LRBA protein deficiency patients. The values obtained by SAP and XIAP antibody staining were 30.2 +/- 3 in CD8+ T cells for SAP, 13.9 +/- 3.2 in CD3+ T and 14.6 +/- 3.5 in CD20+ B cells for XIAP. Since the SAP and XIAP results were not confirmed by gene sequencing, the results were not compared to healthy controls. Conclusion: Due to its rapid and reliable results in clinically relevant cases for DOCK8 and LRBA deficiencies, analysis of protein expression is primarily suitable to evaluate intracellular staining protocol by flow cytometer. In addition, this particular method could be suitable for patients considered to be SAP and XIAP deficient.
Open Access
Investigation of Th17 cell differentiation in immunodeficiencies associated with high IgE levels and/or autoimmunity
(2011-01-01) AKKOÇ, TUNÇ; ÖĞÜLÜR, İSMAİL; AYDINER, ELİF; BARIŞ, SAFA; AKKOÇ T., Tevetoglu A., Ogulur I., Izgi A., AYDINER E., BARIŞ S., Bahceciler N., Barlan I.
Objective: Hyper IgE Syndrome (HIES) and Common Variably Immunodeficiency (CVID) are immuno-deficiency diseases. HIES is characterized by recurrent skin abscesses, pneumonia, mucocutaneous fungal infections, eczama, eosinophilia and high serum IgE levels. CVID is characterized by recurrent bacterial infections in airways and gastrointestinal tract. In this study, differentiation of Th17 cells were aimed to be investigated in CVID and HIES patients.
Open Access
Nijmegen-Breakage Syndrome; Two Siblings Presenting with Different Phenotypes
(BILIMSEL TIP YAYINEVI, 2016-08-25) ÖZEN, AHMET OĞUZHAN; Kiykim, Ayca; Aydiner, Elif Karakoc; Ogulur, Ismail; Baris, Safa; Ozen, Ahmet; Serifov, Kamil; Bademci, Guney; Tekin, Mustafa; Elcioglu, Nursel H.; Barlan, Isil
The Nijmegen Breakage syndrome (NBS) is characterized by chromosomal instability, combined immunodeficiency, and distinctive physical features. We present two siblings with NBS presenting with strikingly different manifestations. The proband is a 6-year-old female with short stature, microcephaly, hepatosplenomegaly, rectovaginal fistula, anal atresia, an ectopic kidney, recurrent fevers and otitis media. A 7-year-old brother has developmental delay, failure to thrive, and microcephaly without recurring infections. Both patients have hypogammaglobulinemia, B cell lymphopenia and reduced phytohaemagglutinin-induced lymphocyte proliferation. Both siblings are homozygous for the c.657_661delACAAA (p.Lys219Asnfs*16) mutation in the NBN (NBS1) gene.
Open Access
Immune system defects in DiGeorge syndrome and association with clinical course
(WILEY, 2019-11) ÖZEN, AHMET OĞUZHAN; Nain, Ercan; Kiykim, Ayca; Ogulur, Ismail; Kasap, Nurhan; Karakoc-Aydiner, Elif; Ozen, Ahmet; Baris, Safa
We evaluated 18 DiGeorge syndrome (DGS) patients and aimed to investigate the immunological changes in this population. DGS patients with low naive CD4(+)T and CD8(+)T cells were defined as high-risk (HR) patients, whereas patients with normal numbers of naive CD4(+) and CD8(+)T cells were defined as standard risk (SR) patients. Level of serum IgM, CD3(+) T cell counts and percentages of class-switched memory B cells were significantly low in HR group compared to SR ones. Severe infections and persistent hypoparathyroidism were detected significantly higher in HR group. Patients with reduced percentages of class-switched B cells had earlier onset of infection, lower blood IgM, lower CD4(+) and CD8(+)T counts than patients with normal class-switched memory B cells. Decreased levels of IgM were associated with low numbers of naive CD4(+) and recent thymic emigrants T cells. Monitoring the immune changes of patients with DGS would be useful to predict the severe phenotype of disease.
Open Access
Lymphocyte Functions in Patients with Chronic Granulomatous Disease and Carrier Individuals
(TURKISH SOC IMMUNOLOGY, 2019) ÖZEN, AHMET OĞUZHAN; Ogulur, Ismail; Baris, Ezgi; Kiykim, Ayca; Baser, Dilek; Akgun, Gamze; Ozen, Ahmet; Baris, Safa; Karakoc-Aydiner, Elif
Introduction: Chronic granulomatous disease (CGD) is classically known as phagocytic system disease. However, in recent years, the observation of the development of autoimmunity, colitis-like findings during follow-up has suggested that the acquired immune system may also be defective. The aim of this project is to investigate the percent of T and B lymphocytes, and function of T lymphocytes in patients with CGD and carriers. Material and Methods: Eleven patients followed for CGD (3 X-CGD, 8 OR-CGD) in our clinic and 6 carrier mothers of OR-CGD were included into the study. The percentages of lymphocytes and their subtypes, lymphocyte proliferation, regulator T cell (Treg), intracellular cytokine content of patients with CDC and carriers we re determined in comparison to healthy controls. Results: There was no statistically significant difference in percentages of T cell, B cell and NK cell and subtypes of T and B cells in the mothers of patients compared to age marched healthy controls. The percentage of naive B cells was significantly higher in the patients with CGD compared to those of healthy subjects (p<0.001). There were no significant differences in lymphocyte proliferation, Treg cell percentage, intracellular IL-17 levels, but IFN-gamma levels were significantly increased in both patients with CDG (p=0.030) and carriers (p=0.038) when compared with age-matched healthy controls. Conclusion: Increased naive B cells were found in CGD patients. High levels of IFN-gamma in patients and carriers need to be further evaluated by further studies. In addition, the normal percentages of Treg and IL-21 in the carriers as in healthy subjects may be offered as the protective mechanism for autoimmunity.