MSCs themselves also support hematopoiesis, as they form part of the market of hematopoietic stem cells (HSCs) and provide the necessary conditions to regulate self-renewal, proliferation, and differentiation [3C6]. transplantation. Because BM offers some drawbacks, umbilical cord blood (UCB) and placenta (PL) have been proposed as you can alternative sources of MSCs. However, MSCs from UCB and PL sources have not been compared to determine which of these cell populations has the best capacity of advertising hematopoietic expansion. In this study, MSCs from UCB and PL were cultured under the same conditions to compare their capacities to support the development of HPCs in vitro. MSCs were cocultured GW438014A with CD34+CD38?Lin? HPCs in the presence or absence of early acting cytokines. HPC development was analyzed through GW438014A quantification of colony-forming cells (CFCs), long-term culture-initiating cells (LTC-ICs), and CD34+CD38?Lin? cells. MSCs from UCB and PL have related capacities to increase HPC development, and this capacity is similar to that offered by BM-MSCs. Here, we are the 1st to determine that MSCs from UCB and PL have related capacities to promote HPC development; however, PL is definitely a better alternate resource because MSCs can be obtained from a higher proportion of samples. 1. Intro Mesenchymal stem/stromal cells (MSCs) are primitive cells that give rise to bone marrow (BM) stromal cells, which are responsible for assisting hematopoiesis [1, 2]. MSCs themselves also support hematopoiesis, as they form part of the market of hematopoietic stem cells (HSCs) GW438014A and provide the necessary conditions to regulate self-renewal, proliferation, and differentiation [3C6]. Earlier results from our group shown the capacity to support hematopoiesis of BM-MSCs in vitro because these cells favor the development of hematopoietic progenitor cells (HPCs) from umbilical wire blood (UCB) [7]. HPCs from UCB using ex lover vivo development systems have been used clinically in individuals undergoing hematopoietic cell transplant (HCT) [8]. Moreover, BM-MSCs have been applied in patients undergoing HCT, resulting in an increase in the graft size and faster hematopoietic recovery [6, 9C11]. Consequently, BM-MSCs are considered a serious candidate for improving HCT. The main source of MSCs is definitely BM; however, the HDAC9 use of BM offers some drawbacks, as obtaining BM is an invasive procedure for the donor [12], and the number of MSCs and their capacities for proliferation and differentiation decrease with the age of the individual [13, 14]. Our study group offers acquired MSCs from neonatal sources, such as umbilical cord blood (UCB) and the placenta (PL). It is noteworthy the proportion of PL samples from which we were able to obtain MSCs was higher than that of UCB samples (100% and 11%, resp.) [15]. Moreover, for the two sources, we showed that their morphologies, immunophenotypes, and capacities for osteogenic and chondrogenic differentiation are similar to those of BM-MSCs [15] and that they possess immunosuppression capacities [16, 17]. Additional groups have shown that MSCs from UCB [18] and PL [19] have the capacity to support hematopoiesis in vitro but have not compared these cell types to determine which type has the best capacity for potential clinical software. In this study, we used the same coculture conditions to compare the capacities of MSCs from UCB and PL to support the in vitro development of HPCs from an enriched human population of UCB CD34+CD38?Lin? cells. MSCs from BM were included like a control. Our results demonstrate that MSCs from UCB and PL have related capacities to support HPC development, and this capacity is similar to that of BM-MSCs. 2. Materials and Methods 2.1. Collection and Tradition of MSCs from BM, UCB, and PL BM samples were from hematologically healthy donors according to the Declaration of Helsinki and the Local Ethics Committee of Villacoapa Hospital, Mexican Institute for Sociable Security (IMSS). UCB and PL samples were collected according to the Declaration of Helsinki and the Local Ethics Committee of the Troncoso Hospital (IMSS, Mexico). MSCs from BM (= 6), UCB (= 6),.