Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 225 229 EN Samin Sharafian Department of Allergy and Clinical Immunology, School of Medicine, Bushehr University of Medical Sciences, Bushehr, Iran Masoud Movahedi Department of Allergy and Clinical Immunology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran Arash Kalantari Department of Allergy and Clinical Immunology, Vali-e-Asr Hospital, Imam Khomeini Hospital Complexes, Tehran University of Medical Sciences, Tehran, Iran Nima Parvaneh Department of Allergy and Clinical Immunology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran Mohammad Gharagozlou Department of Allergy and Clinical Immunology, Children’s Medical Center, Tehran University of Medical Sciences, Tehran, Iran 2018 01 25 2018 07 04 Hyperimmunoglobulin E syndrome (HIGE) is considered as a phagocytic or a newly classified complex and heterogeneous primary immunodeficiency disease with symptoms such as increased levels of immunoglobulin E, eczema, and, recurrent lung and skin infections. In this paper, we have presented a rare case of this syndrome. A 9-year-old Iranian girl presented with a history of pruritic maculopapular rash who was eventually diagnosed as a case of HIGE. In her recent admission, she had dysphonia, stridor and huge cauliflower cutaneous lesions on her neck, finger and vocal cords, which did not respond to intravenous antibiotics, and ultimately required surgical removal. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1836 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1836/1403

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 120 130 EN Zohreh Jadali Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2017 12 17 2018 08 19 CD4+T cells are composed of different subpopulations that differ in developmental pathways, surface markers, and their products. Among the catalog of these cells is Th9 cell subset that has a great capacity of Interleukin (IL)-9 production. They could be involved in the pathogenic or protective immune responses. Therefore, it is important to know how Th9 cells and cytokines influence the function of the human immune system as multitasking machinery, both in isolation or after the interaction with other surrounding cells. Since an important characteristic of Th9 cells is their tropism for skin, this article reviews the physiological and pathophysiological functions of Th9 and its cytokines under normal conditions and inflammatory skin disorders. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1788 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1788/1391

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 131 142 EN Arefeh Jafarian Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Gelareh Shokri Stem Cell Technology Research Center, Tehran, Iran Mahdieh Shokrollahi Barough Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran AND Department of Cancer Immunotherapy and Regenerative Medicine, Breast Cancer Research Center, Motamed Cancer Institute, Academic Center for Education, Culture and Research (ACECR), Tehran, Iran Mostafa Moin Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Zahra Pourpak Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Masoud Soleimani Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran 2018 02 12 2018 07 15 The Chronic granulomatous disease (CGD) is a primary immunodeficiency that characterized by mutations in phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, resulting in deficient antimicrobial activity of phagocytic cells and recurrent childhood infections. Hematopoietic stem cell transplantation (HSCT) is a curative option for patients with human leukocyte antigen (HLA) matched donor, when conventional cares and therapies fail. However, in many cases when the patients have not an HLA-matched donor, they need to a method to recapitulate the function of the affected gene within the patient’s own cells. Gene therapy is a promising approach for CGD. While, the success of retroviral or lentiviral vectors in gene therapy for CGD has been hampered by random integration and insertional activation of proto-oncogenes. These serious adverse events led to improvement and generations of viral vectors with increased safety characteristics. Gene therapy continues to progress and the advent of new technologies, such as engineered endonucleases that have shown a great promise for the treatment of genetic disease. This review focuses on the application of gene therapy for the CGD, the limitations encountered in current clinical trials, advantages and disadvantages of endonucleases in gene correction and modeling with CRISPR/Cas9 approach.  https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1868 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1868/1392

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 143 152 EN Leila Shakerian Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Zahra Pourpak Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Somayeh Shamlou Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran Erna Domsgen ImmunoIVD, Nacka Strand, Nacka, Sweden Anoshirvan Kazemnejad Department of Biostatistics, Tarbiat Modares University, Tehran, Iran Hossein Dalili Breastfeeding Research Center, Tehran University of Medical Sciences, Tehran, Iran Maryam Nourizadeh Immunology, Asthma and Allergy Research Institute, Tehran University of Medical Sciences, Tehran, Iran 2018 04 15 2018 06 19 Assessment of the number of T-cell receptor excision circles (TREC) and kappa-deleting recombination excision circles (KREC) copies has been recently described as biomarkers of newly formed T and B cells respectively. In this study, we aimed to explore the effects of demographic variables including age, gender, weight, height and ethnicity on these two episomal DNA molecules. Second, for the first time in our country, we determined the reference values of TREC and KREC copy numbers in different age groups of Iranian healthy individuals as a threshold for identifying T cell and B cell lymphopenia. The TREC and KREC copy numbers were evaluated in 251 dried blood spot (DBS) samples from healthy volunteers (age range: 0-60 years). Six primary immunodeficiency (PID) patients were included as disease controls. TREC and KREC copies were markedly reduced with increasing age. Although the levels of TREC and KREC were higher in females than males, this difference did not reach statistical significance. These findings suggest that demographic variables including age should be considered for interpretation results of the TREC/KREC assay. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1907 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1907/1409

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 153 162 EN Atefeh Nasir Kansestani Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran AND Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran Kamran Mansouri Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran Shahrooz Hemmati Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran Mohammad Erfan Zare Student Research Committee, Kermanshah University of Medical Sciences, Kermanshah, Iran AND Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran Ali Moatafaei Medical Biology Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran 2017 12 04 2018 06 09 Tumor cells rely on glycolysis for their energy supply with the production of lactate even in normoxia condition, which is named aerobic glycolysis or Warburg effect. Therefore, high glucose (HG) concentration provides a favorable condition for increasing proliferation, angiogenesis and decreasing apoptosis, but its molecular mechanisms are still unknown. The objective of this study is to investigate HG condition on tumor cells behavior including proliferation, apoptosis, and an angiogenesis mediator. In this study, MCF-7 derived from human breast adenocarcinoma, were cultured in DMEM with two different concentrations of glucose for 48 h (5.5 mM as normal glucose (NG) condition and 25 mM as HG condition). We used Zingiber officinale extraction for the inhibition of NF-κB. Cell proliferation assay was done by direct counting, cell viability by MTT method, bcl-2 by Immunocytochemistry, apoptosis by Hoechst/PI double staining and vascular endothelium growth factor (VEGF) by ELISA. Results showed that HG increased lactate production, significantly. HG increased cell proliferation, cell viability, VEGF secretion, and bcl-2 expression while it decreased apoptosis. However, when HG was combined with Zingiber officinale extraction, cell proliferation, cell viability, VEGF secretion and bcl-2 expression decreased and apoptosis increased significantly due to inhibition of NF-κB. Results revealed that HG increased cell proliferation, angiogenesis and decreased apoptosis due to activation of NF-κB pathway. Moreover, the probable mechanism of the activation of NF-κB in HG is increasing reactive oxygen species (ROS) in this condition that can activate NF-κB directly. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1761 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1761/1406

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 163 172 EN Zahra Kanannejad Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran Bahia Namavar Jahromi Department of Gynecology and Obstetrics, Shiraz University of Medical Sciences, Shiraz, Iran AND  Infertility Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Behrouz Gharesi-Fard Department of Immunology, Shiraz University of Medical Sciences, Shiraz, Iran AND Infertility Research Center, Shiraz University of Medical Sciences, Shiraz, Iran 2019 01 06 2019 03 04 Unexplained infertility (UI) is one of the most common diagnoses in the fertility care. Seminal plasma (SP) plays a crucial role in the regulation of female immune responses and the success of a pregnancy. In vitro fertilization (IVF) is a well-known method for the treatment of UI. In this study, we aimed to investigate the effect of SP on the differentiation of T helper (Th) cell subsets and the relationship between these subsets with the rate of IVF success in a group of women complicated with UI compared to those with normal pregnancy. This study was conducted on 20 UI couples (ten with successful and ten with unsuccessful IVF outcome) and 10 fertile couples as the control group. Four color flow cytometry technique was used to detect Th cell subsets in the peripheral blood mononuclear cells (PBMC) with or without stimulation by SP. Results indicated that the frequencies of IL-17+ and Foxp3+ T cells after incubation with SP was significantly increased in couples with unsuccessful IVF outcome as compared to successful and healthy groups (p<0.05). Additionally, a positive correlation was observed between Th1 and Th2 cells in the unsuccessful IVF group (R=0.6, p=0.03). In summary, the results of the present study demonstrated that exposure to SP might increase Th17 and Treg cell frequencies in infertile women with unsuccessful IVF, and might also balance inflammatory to regulatory responses to finally tune-up the Th1/Th2/Th17/Treg balance and support the success of IVF. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/2262 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/2262/1414

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 18 2 2019 04 01 173 181 EN Pegah Vahidi Manesh Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran AND Department of Cell and Molecular Biology, University of Tehran, Tehran, Iran Ali Farazmand Department of Cell and Molecular Biology, University of Tehran, Tehran, Iran Farhad Gharibdoost Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Negar Vanaki Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Shayan Mostafaei Department of Community Medicine, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran Hoda Kavosi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Mohammad Bagher Mahmoudi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Mahdi Mahmoudi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran ROR-γt and those of the cytokines IL-4, IL-5, IL-13, and IL-17, representing both T helper (Th)2 and Th17 responses, were lower in the IL-37 group in comparison with the Der f group. However, the Th1 responsewas not suppressed after administration of IL-37. IL-37 increased the IL-10 level; however, Real-Time PCR, western blotting, and flow cytometry results showed the limited action of IL-37 on CD4+CD25+Foxp3+T cells. This study demonstrates that intranasal IL-37 can suppress Th2 and Th17 responses in an AR murine model. Furthermore, these data suggest that IL-10 is increased, but CD4+CD25+Foxp3+T cells are not correlated with the IL-37-induced mechanism.   https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1104 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1104/762

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 418 424 EN Mohammad Taghi Palizgir Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Maryam Akhtari Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran AND Department of Cell and Molecular Biology, University of Tehran, Tehran, Iran Mahdi Mahmoudi Rheumatology Research Center, Tehran University of Medical Sceinces, Tehran, Iran Shayan Mostafaei Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Alireza Rezaeimanesh Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran Massoomeh Akhlaghi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran Farhad Shahram Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran 2017 03 07 2017 05 16 Aryl hydrocarbon receptor (AHR) is a ligand-activated transcription factor, connecting environmental stimulators with the immune system. M1 macrophages are a part of immune system that contribute to the inflammatory events in the pathogenesis of Behcet's disease (BD). The effect of AHR on the macrophages in BD patients is still unclear. In this study, we investigated the mRNA expression of AHR in the monocyte-derived and M1 macrophages in active BD patients in comparison to healthy controls. Isolated monocytes from 10 healthy controls and 10 active BD patients were differentiated to macrophages by macrophage-colony stimulating factor (M-CSF) for 7 days. Cells were then polarized to M1 macrophages by lipopolysaccharide (LPS) and interferon-γ (IFNγ) for 24h. Monocyte purity and macrophage markers expression were analyzed by flow cytometry. Analysis of AHR mRNA expression was performed by SYBR Green real-time PCR. Our results showed that AHR expression is significantly down-regulated in M1 macrophages compare to monocyte-derived macrophages. It was shown that both monocyte-derived macrophages and M1 macrophages from BD patients significantly express lower level of AHR mRNA compared to healthy individuals. Our results demonstrate an anti-inflammatory role for AHR in macrophages, which suggest that decreased AHR expression is associated with pro-inflammatory M1 macrophage and BD susceptibility. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1350 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1350/774

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 425 432 EN Tahereh Khamehchian Department of Pathology, Kashan University of Medical Sciences, Kashan, Iran Eqlim Nemati Internal Medicine Department, Baqiyatallah University of Medical Sciences, Tehran, Iran Marziyeh Jazayeri Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran shirin Azimi Student Research Committee, Kashan University of Medical Sciences, Kashan, Iran Hassan Nikoueinejad Nephrology and Urology Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran Hossein Akbari Trauma Research Center, Kashan University of Medical Sciences, Kashan, Iran Behnaz Irandoust Department of Pathology, Kashan University of Medical Sciences, Kashan, Iran 2017 03 04 2017 05 13 Type 1 diabetes (T1D) is the result of the autoimmune destruction of insulin-producing beta cells. Regulatory T cells (Tregs) and plasmacytoid dendritic cells (PDCs) act as mediators of peripheral tolerance. We investigated the possible alterations of such cells in peripheral blood of patients with T1D compared to normal individuals. This comparison may lead to a better understanding of the immunopathogenesis processes involved in T1D. 92 participants, including 49 patients with T1D and 43 healthy controls were studied. 3 mL of blood was taken from all participants. After isolating peripheral blood mononuclear cells (PBMCs), PDCs as well as 2 subtypes of Tregs, CD4+CD25+FoxP3+ and CD8+CD28- cells were counted by 3-colorflow cytometry. The association between such enumeration and T1D was studied by multivariate regression and discriminate function models. The frequency of CD4+CD25+FoxP3+Tregs (p=0.038) and PDCs (p=0.039) in the peripheral blood of diabetic patients was less than that in healthy subjects. Having compared some models consisting different cells as well as their combinations, we did not find any profound explanation of each subset or their combinations to identify T1D. The decrease of CD4+CD25+FoxP3+cells and PDCs in diabetic patients may suggest their role in the onset or development of the disease. Therefore, it is likely that their pharmacologic stimulation may direct immune responses towards tolerance and prevent the development or even the onset of diabetes in susceptible individuals. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1343 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1343/768

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 433 442 EN Hossein Ahmadi Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Ahmad Reza Jamshidi Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mahdi Mahmoudi Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Farhad Gharibdoost Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mahdi Vojdanian Rheumatology Research Centre, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Mohammad Javad Fattahi Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Institute for Cancer Research (ICR), School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran Noushin Rastkari Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Zahra Aghazadeh Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Abbas Mirshafiey Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2017 01 23 2017 03 12 The aim of this study was to investigate the effect of β-D-mannuronic acid (M2000) on hematological parameters in patients with active rheumatoid arthritis. This study was conducted on 25 patients with active rheumatoid arthritis (RA) (identifier: IRCT2014011213739N2). M2000 was administered orally for anemic and non-anemic RA patients at a dose of 500 mg twice daily for 12 weeks. The patients were permitted to continue the conventional treatments excluding NSAIDs. Blood samples were collected at baseline, 4 and 12 weeks after drug administration and were tested for hematological parameters. Moreover, serum levels of TNF-α and IL-6 were analysed before and after M2000 therapy compared to healthy controls using enzyme linked immunosorbent assay method. We found a significant increase in the count of red blood cells and also hemoglobin (Hb) concentration (0.9 g/dL) in anemic patients after 12 weeks of M2000 therapy (p<0.02 and p<0.01, respectively). Furthermore, our results showed an improvement in Hb level (0.45 g/dL) even in non-anemic patients who were treated by M2000 (p<0.04). The leukocytosis in RA patients, significantly decreased in both anemic and non-anemic patients after 12 weeks of M2000 therapy (p<0.02 and p<0.03, respectively). The percent of neutrophils significantly increased in anemic patients (p<0.01) while in non-anemic patients it significantly decreased after 12 weeks of M2000 therapy (p<0.01). The serum levels of IL-6 and TNF-α significantly decreased after 12 weeks of M2000 therapy (p<0.01 and p<0.04, respectively). M2000 improves hematological parameters in RA patients by its potent inhibitory effect on serum levels of TNF-α and IL-6. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1275 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1275/761

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 443 451 EN Mohadese M. Farahani Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Elahe Motevaseli Department of Molecular Medicine, School of Advanced Technologies in Medicine, Tehran University of Medical Sciences, Tehran, Iran Faezeh Maghsood Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Maryam Heidari-Kharaji Department of Immunotherapy and Leishmania Vaccine Research, Pasteur Institute of Iran, Tehran, Iran Abbas Mirshafiey Department of Immunology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran 2016 11 16 2017 04 05 The aim of this study was to evaluate the effects of M2000, a novel non-steroidal anti-inflammatory drug (NSAID) with immunosuppressive property and without gastro-nephrotoxicitic effects on matrix metalloproteinases (MMP)-2 and (MMP)-9 in phorbol myristate acetate (PMA)-differentiated THP-1 cells. Gene expression and activity of MMP-2 and MMP-9 are inhibited respectively by the tissue inhibitor of matrix metalloproteinase (TIMP)-2 and (TIMP)-1 and are induced by extracellular matrix metalloproteinase inducer (CD147/EMMPRIN). In this study, real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was used to determine gene expression of MMP-2, MMP-9, TIMP-1, and TIMP-2. Flow cytometry and zymography were applied to determine cellular surface expression of CD147 and activity of MMP-2 and MMP-9, respectively. Our results showed that treatment of THP-1 cells with high concentration (25 µg/mL) of M2000 significantly decreased the cellular surface expression of CD147 (p<0.05) and the gene expression of MMP-2, MMP-9 and TIMP-1 (p<0.05), and inhibited the gelatinolytic activity of MMP-2 and MMP-9 (p<0.05). According to our results, M2000 can reduce inflammation through inhibition of the cellular surface expression of CD147 and decrease the gene expression and gelatinolytic activity of MMP-2 and MMP-9 in PMA-differentiated THP-1 cells. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/1148 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/1148/773

Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 16 5 2017 10 28 452 456 EN Demeke Geremew Department  of  Immunology,  School  of  Medicine,  International  Campus,  Tehran  University  of  Medical  Sciences, Tehran, Iran AND Department of Immunology and Molecular Biology, School of Biomedical and Laboratory Sciences, University of Gondar (UoG), Gondar, Ethiopia Ania Rahimi-Golkhandan Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Khosro Sadeghniiat-Haghighi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran Yadollah Shakiba Department of Immunology, School of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran Ahmad khajeh-Mehrizi Occupational Sleep Research Center, Baharloo Hospital, Tehran University of Medical Sciences, Tehran, Iran AND Department of Internal Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Bita Ansaripour Department  of  Immunology,  School  of  Medicine,  International  Campus,  Tehran  University  of  Medical  Sciences, Tehran, Iran Maryam Izad Department  of  Immunology,  School  of  Medicine,  International  Campus,  Tehran  University  of  Medical  Sciences, Tehran, Iran 2016 11 11 2017 04 18 Narcolepsy is a rare, disabling disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucinations and sleep paralysis. Several studies demonstrated its association with HLA-DQB1*0602 in various ethnic groups. Our study aimed to determine the prevalence of HLA-DQB1*0602 allele in Iranian patients with narcolepsy and assess its predictive parameters for diagnosing narcolepsy. In addition, car accidents and job problems were assessed among narcoleptic patients. We studied 44 narcoleptic patients, 30 patients with other types of excessive daytime sleepiness (EDS)  and 50 healthy age and sex matched individuals in this case-control study. Patients and controls filled out a questionnaire including items about car accidents due to sleepiness and job problems. International classification of sleep disorders-2 criteria was used as the gold standard for diagnosis of narcolepsy. The DNAs isolated from whole blood samples were collected from the patients and controls to assess the presence of HLA-DQB1*0602. The results showed that HLA DQB1*0602 was present in 4 (8%) individual of controls and 20 (45.5%) patients with higher prevalence in patient