en Stem Cell Stem Cell Original Article Original Article <div style="text-align: justify;">The feasibility of isolating and manipulating mesenchymal stem cells (MSCs) from human patients provides hope for curing numerous disease and disorders. Recent phenotypic analysis showed heterogeneity of MSCs. A nestin progenitor cell is a subpopulation within MSCs which plays a role in pancreas regeneration during embryogenesis. This study aimed to separate nestin ⁽⁺⁾ cells from human bone marrow-MSCs, and differentiate these cells into functional insulin-producing cells (IPCs) compared with nestin ^(-) cells. Manual magnetic separation was performed to obtain nestin ⁽⁺⁾ cells from MSCs. Approximately 91&plusmn;3.3% of nestin ⁽⁺⁾ cells were positive for the anti-nestin antibody. Pluripotent genes were overexpressed in nestin ⁽⁺⁾ cells compared with nestin ^(-) cells as revealed by quantitative real time-PCR (qRT-PCR). Following <em>in vitro</em> differentiation, flow cytometric analysis showed that 2.7&plusmn;0.5% of differentiated nestin ⁽⁺⁾ cells were positive for anti-insulin antibody in comparison with 0.08&plusmn;0.02% of nestin ^(-) cells. QRT-PCR showed higher expression of insulin and other endocrine genes in comparison with nestin ^(-) cells. While the immunofluorescence technique showed the presence of insulin and C-peptide granules in nestin ⁽⁺⁾ cells. Therefore, our results introduced nestin ⁽⁺⁾ cells as a pluripotent subpopulation within human MSCs which is capable to differentiate and produce functional IPCs.</div> Human bone marrow derived mesenchymal stem cells, insulin producing cells, real time-quantitative PCR, mesenchymal stem cells, diabetes mellitus 1 13 http://ijmcmed.org/browse.php?a_code=A-10-1800-2&slc_lang=en&sid=1 Sahar Rashed saharrashed89@gmail.com 100319475328460015975 100319475328460015975 No Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Mahmoud Gabr mgabr24@yahoo.com 100319475328460015976 100319475328460015976 No Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Abdel-Aziz Abdel-Aziz afaziz2012@hotmail.com 100319475328460015977 100319475328460015977 No Biochemistry Division, Chemistry Department, Faculty of Science, Mansoura University, Mansoura, Egypt. Mahmoud Zakaria mahmoudzakaria2004@yahoo.com 100319475328460015978 100319475328460015978 No Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Sherry Khater ahshmowa4@yahoo.com 100319475328460015979 100319475328460015979 No Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Amani Ismail amani_mostafa@hotmail.com 100319475328460015980 100319475328460015980 No Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Ali Fouad alifouad.b@gmail.com 100319475328460015981 100319475328460015981 Yes Department of Biotechnology, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt. Ayman Refaie ayman_refaie@yahoo.com 100319475328460015982 100319475328460015982 No Nephrology Department, Urology and Nephrology Center, Mansoura University, Mansoura, Egypt.