International Journal of Medical Laboratory

en بررسی شکست کروموزومی واصلاح آن در سلولهای تکثیر یافته CD34 مثبت هماتو پوئیتک استم سل Evaluation of DNA Damage and Repair In In Vitro Expanded Cord Blood CD 34 Positive Hematopoietic Stem Cell خون شناسی و بانک خون Hematology & Blood Banking پژوهشي Research هدف : یکی از منابع استم سل جهت پیوند، سلول های بندناف میباشد،شیوع شکست کروموزومی یک رشته یا دو رشته یکی از موانع مهم در ثکثیر سلول های بندناف می باشد. شکست کروموزومی می تواند نتایج ناخواسته از جمله موتاسیون، مرگ سلولی را به دنبال داشته باشد. مطالعه کنونی به منظور بررسی صدمات به DNA و ژنهای مشارکت کننده در ترمیم DNA پس از کشت سلولی انجام شده شده است. روش ها و متدها : خون بندناف با روش MACS جدا شده با روش فلوسیتومتری مرگ سلولی بررسی شد. برای برسی شکست کروموزومی از روش comet assay استفاده شد نتایج: تعداد سلولها بعد از کشت به مدت سه روز 9/1 برابر شد. تعداد سلولهای مرده کم و قابل اغماض (2/0%) می باشد. با بررسی ژنهای دخیل در ترمیم DNA مثل  KU70 ، KU80،RAD51 و XRCC1 مشخص شدافزایش قابل توجهای نداشته است. نتیجهگیری: شکست کروموزومی قابل توجه و صدمه به DNA ملاحظه نشد.   <div style="text-align: justify;">Background and Aims: The occurrence of single and double-strand breaks of DNA damage is the major obstacle for proliferation under various environmental factors and, if not repaired, can result in many consequences, including mutation, cell death, and others. So, the present study was conducted to evaluate the damage of DNA and the expression status of DNA repair system genes before and after stem cell proliferation. Materials and Methods: The MACS method isolated the umbilical cord blood hematopoietic stem cells (UCB-HSCs). In order to investigate cell death, the study of Annexin V/PI was done by flow cytometry. Comet assay made observation and identification of DNA breaks, and the expression of genes normally involved in the repair of DNA breaks was evaluated by real-time polymerase chain reaction. Results: The average number of stem cells increased by 1.9-fold after three days of proliferation. The apoptotic percentage of cells was negligible (less than 0.2%), and the purity of the CD34+ cells was reduced by about one-third in three days (67%). By examining the expression of DNA repair genes, including KU70, KU80, RAD51, and XRCC1, their increased fold change was not significant. In a microscopic examination of stem cells in the comet assay, there was no significant difference between DNA damage before (1.33% ± 0.31) and after (2.08% ± 0.92) replication. Conclusion: In our investigation, neither DNA damage nor changes in the DNA break repair were observed. However, further studies are required to clarify the DNA break repair by recruiting more UCB-HSCs samples.</div> Comet assay تست , ژن Ku80 , ژن KU70 , Cord blood stem cells, DNA damage, Comet assay, Ku80, KU70 46 56 http://ijml.ssu.ac.ir/browse.php?a_code=A-10-463-2&slc_lang=en&sid=1 Mohammad Shokouhian محمد شکوهیان mohammad.shekuhian@yahoo.com 0000-0001-5061-7058 Yes Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran Hossein Mozdarani حسین مزدارانی mozdarah@modares.ac.ir 0000-0003-2080-3287 No Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Department of Medical Genetics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Masoud Soleimani مسعود سلیمانی soleim_m@modares.ac.ir 0000-0002-5269-7829 No Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran Majid Safa مجید صفا majidsafa@gmail.com 0000-0002-8247-5282 No Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran Mohammad Reza Rezvany محمد رضا رضوانی mohrezrez@yahoo.com 0000-0003-0323-7671 No Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran. Pediatric Growth and Development Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran. Department of Oncology-Pathology, BioClinicum, Karolinska University Hospital Solna and Karolinska Institute, Stockholm 17176, Sweden Department of Hematology and Blood Transfusion, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran. Pediatric Growth and Development Research Center, Institute of Endocrinology and Metabolism, Iran University of Medical Sciences, Tehran, Iran. Department of Oncology-Pathology, BioClinicum, Karolinska University Hospital Solna and Karolinska Institute, Stockholm 17176, Sweden