In the present study, all bone marrow samples (hBM-MSCs and dBM-MSCs) were cultured in a medium supplemented with 10% UCBS. analyzed whether in vitro reprogramming could afford the maturation of the islet-like clusters (ICAs) derived from dBM-MSCs. Upon mimicking the diabetic hyperglycemic niche and the supplementation of fetal pancreatic extract, to differentiate dBM-MSCs into pancreatic lineagein vitro, we observed quick differentiation and maturation of dBM-MSCs into islet-like cell aggregates. Thus, our study exhibited that diabetic hyperglycemic microenvironmental milieu plays a major role in inducing the BIO differentiation of human BM-MSCsin vivoandin vitro. Keywords:diabetes, beta-cell, stem cell, differentiation, bone marrow, NGN3, NKX6.1, PAX6 Abbreviations: -MEM – -modified Eagle’s medium (utilized for cell culture); AGE – advanced glycation end-product; BIO ALL – acute lymphoblastic leukemia; ALS – amyotrophic lateral sclerosis; AML – acute myeloid leukemia; BM-MSC – bone marrow-derived mesenchymal stem cell; BRN4 – Brain 4 (transcription factor expressed in the brain and glucagon-expressing cells in the pancreas, also known as POU3F4); C-peptide – connecting peptide; Ct – cycle threshold; CXCR4 – alpha-chemokine receptor (also called fusin) specific for stromal-derived-factor-1 (SDF-1, also called CXCL12), a molecule endowed with potent chemotactic activity for lymphocytes; dBM-MSC – human diabetic BM-MSC; DME meduim – Dulbecco’s altered Eagles medium; E-cadherin – epithelial cadherin (CDh1); EDTA – ethylenediaminetetraacetic acid (used as chelating agent that binds to calcium and prevents joining of cadher-ins between cells; it also prevents clumping of cells produced in liquid suspension, and is able to detach adherent cells for passaging); EGFP – enhanced green fluorescence protein; F(ab)2 – antigen-binding Rabbit Polyclonal to MYOM1 fragment of an antibody; FACS – fluorescence-activated cell sorting; GATA6 – binding protein that binds (A/T/C)GAT(A/T)(A) of the binding sequence; Glut2 – glucose transporter 2 (also known as solute carrier family 2 member 2 SLC2A2); GCG – glucagons gene; hBM-MSC – normal human BM-MSC; HD – Hodgkin disease; ICA – islet-like cell aggregate; ICAM-5 – intercellular adhesion molecule 5 (also known as telencephalin, CD# not yet assigned); ISL1 – insulin gene enhancer protein gene 1; NCAM-1 – neural cell adhesion molecule 1 (CD56); NDS – normal donkey serum; NGN-3 – neurogenin-3 (controls islet cell fate specification in pancreatic progenitor cells); NHL – non-Hodgkin lymphoma; NKX6-1 – NK6 homeobox 1 (transcription factor required for the development of beta-cells); Oil-Red-O – Solvent Red 27 (fat-soluble dye utilized for stain-ing of triglycerides and lipids); PBS – phosphate-buffered saline; PECAM-1 – platelet endothelial cell adhesion molecule-1 (CD31); PE – phycoerythrin (fluorescent dye for labeling antibodies); Pdx1 – pancreatic and duodenal homeobox 1 (transcription factor necessary for pancreatic development and beta-cell maturation); PFA – paraformaldehyde (used to fix cells); POU – class of genes that produce transcription factors; BIO POU3F4 – POU class 3 homeobox 4 gene or gene product (also known as BRN4); RNA – ribonucleic acid; RPE – rat pancreatic extract; RT-PCR – reverse transcriptase polymerase chain reaction; TPVG – trypsin phosphate versene glucose; UCBS – human umbilical cord blood serum == Introduction == Bone marrow-derived mesenchymal stem cells (BM-MSCs) are able to differentiate into many cell types, and to proliferate ex lover vivo. These characteristics makes them a potential therapeutic tool for cell replacement therapy in diabetes and other diseases. Stem cell differentiation is usually controlled by extracellular cues, the environment, and intrinsic genetic programs within stem cells [1,2]. The fate of stem cell differentiation is usually influenced by both soluble and insoluble factors from the surrounding microenvironment. Several signaling cascades mediate the balance response of the stem cell to the need of the organism. Pathological conditions induced by dysregulation result in aberrant functions of stem cells or other targets [3-6]. Previous studies have exhibited the characteristics of BM-MSCs isolated from healthy donors [7,8]. BM-MSCs typically lack hematopoietic antigens like CD45, CD34, and CD14, express mesenchymal antigens such as CD105, CD90, CD73, CD44, and CD29, exhibit self-renewal potential, and are able to differentiate into multiple lineages. Whereas, the characteristics and differentiation potential for BM-MSCs obtained from diabetic individuals are BIO unknown. Optimization of theirin vitroexpansion and characterization of disease-specific BM-MSCs would provide crucial information to maximize the beneficial effects of autologous BM-MSC therapy in diabetes [9]. Studies have shown.