objective: allogeneic transplantation with umbilical cord blood (ucb) in adult recipients is limited mainly by a low cd34+ cell dose. to overcome this shortcoming, human placenta as a novel source of human mesenchymal progenitor cell (mpc)- unrestricted somatic stem cells (ussc)- was incorporated in an attempt to expand cd34+ cells from ucb. to provide a similar environment in vitro, we coated ...

Background: It is still controversial that the stem cells isolated from human dental pulp meets the criteria for mesenchymal stem cells (MSCs). The aim of the present study was to examine whether or not they are MSCs, or are distinct stem cells population residing in tooth pulp. Methods: Adherent fibroblastic cells in the culture of pulp tissue from human third molars were propagated through se...

Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34(+) hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-...

Blood cells transplantation is largely replacing bone marrow transplantation because engraftment is more rapid. This accelerated engraftment is thought to be mediated by relatively mature committed hematopoietic progenitor cells. Herein, we have used a modified rhodamine (Rho) staining procedure to identify and purify Rho+/++ (dull/bright) and Rho- (negative) subpopulations of hematopoietic pro...

Studies on hematopoiesis have focused on the function and composition of human bone marrow stroma. Stroma function gives hematopoietic stem cells the microenvironment appropriate for self-renewal and/or prompt differentiation into hematopoietic progenitor cells, then into terminal specialized cells. Human bone marrow stroma has been dissected into hematopoietic and nonhematopoietic components. ...

One of the most important tasks biotechnology and regenerative medicine is to achieve long-term expansion hematopoietic stem cells. promising approaches optimizing cultures cells creation a microenvironment in form feeder stromal layers, which allows for reproduction combination soluble cytokines growth factors necessary hematopoiesis promotes an increase their proliferation [1,2].

The ability of the many cell types within the adult blood system to be constantly replenished and renewed from hematopoietic stem cells is an interesting problem in development and differentiation and has led to questions concerning how, when and where these stem cells for the adult hematopoietic system are generated within the embryo. During embryonic development many mature hematopoietic cell...

Objective(s): In this paper, we discussed natural agents with protective effects against stem cell senescence. Different complications have been observed due to stem cell senescence and the most important of them is “Aging”. Senescent cells have not normal function and their secretary inflammatory factors induce chronic inflammation in body which causes different patho...

Hematopoietic stem cells in the bone marrow have the capacity to both self-renew and to generate all cells of the hematopoietic system. The balance of these two activities is controlled by hematopoietic stem cell-intrinsic regulatory mechanisms as well as extrinsic signals from the microenvironment. Here we demonstrate that Meis1, a TALE family homeodomain transcription factor involved in numer...