Biomedical subjects

A Erices

Publications and source records attributed to A Erices.

4 recordsLinked to original sources

PubMed2001

Mesenchymal stem cells.

Within the bone marrow stroma there exists a subset of nonhematopoietic cells referred to as mesenchymal stem or mesenchymal progenitor cells. These cells can be ex vivo expanded and induced, either in vitro or in vivo, to terminally differentiate into osteoblasts, chondrocytes, adipocytes, tenocytes, myotubes, neural cells, and hematopoietic-supporting stroma. The multipotential of these cells, their easy isolation and culture, as well as their high ex vivo expansive potential make these cells an attractive therapeutic tool. In this work we will review the information dealing with the biology of mesenchymal progenitors as it has been revealed mainly by ex vivo studies performed with bone marrow-derived cells. The discussed topics include, among others, characteristics of mesenchymal progenitors, evidence for the existence of a vast repertoire of uncommitted and committed progenitors both in the bone marrow and in mesenchymal tissues, a diagram for their proliferative hierarchy, and comments on mobilization, microenvironment, and clinical use of mesenchymal progenitors. Despite the enormous data available at molecular and cellular levels, it is evident that a number of fundamental questions still need to be resolved before mesenchymal progenitors can be used for safe and effective clinical applications in the context of both cell and gene therapies.

Animals↗

PubMed2000

Characterization of the oligosaccharides of plasma sex hormone binding globulin from noncirrhotic alcoholic patients.

In previous reports we have demonstrated high plasma levels of sex hormone-binding globulin (SHBG) in asymptomatic alcoholic men. In the present work the physicochemical properties of SHBG from plasma of noncirrhotic alcoholic patients have been further compared with SHBG of control subjects. Steroid binding to SHBG was similar for the two groups: alcoholic men, K(d) of 0.62 +/- 0.07 nM and control individuals, K(d) of 0.70 +/- 0.10 nM. The structure of oligosaccharides attached to SHBG from controls and alcoholic men were determined by using serial chromatography. Our data indicated that 7% of SHBG of control individuals was not retarded by the Con-A column, whereas approximately 30% of SHBG of alcoholic men eluted in the void volume of Con A. Approximately 46% of SHBG of alcoholics applied to Con A, possessed biantennary complex oligosaccharides, as indicated by the fact that it could be eluted with methyl-alpha-D-glucopyranoside and by its retention on wheat germ agglutinin; in contrast, when SHBG from control men was analyzed, approximately 51% was eluted with methyl-alpha-D-glucopyranoside. Approximately 9% of the biantennary complex oligosaccharides on SHBG of control men and none of those on SHBG from alcoholic men were fucosylated on the chitobiose core, as determined by chromatography on Lenn culinaris lectin. Galactosylated oligosaccharides were also present on the SHBG fraction as indicated by its interaction with Ricinus communis-I. Approximately 24% of SHBG of alcoholic men and 39% of those on SHBG from control individuals applied to Con-A were retained and could be eluted with methyl-alpha-D-mannopyranoside. Evidence based on the binding on mannoside-eluted SHBG to Con-A, wheat germ agglutinin, and R. communis-I indicated that at least the SHBG in this fraction, from alcoholics or controls, contained two glycosylation sites and that the sites were differentially glycosylated.

Adult↗

PubMed2000

Mesenchymal progenitor cells in human umbilical cord blood.

Haemopoiesis is sustained by two main cellular components, the haematopoietic cells (HSCs) and the mesenchymal progenitor cells (MPCs). MPCs are multipotent and are the precursors for marrow stroma, bone, cartilage, muscle and connective tissues. Although the presence of HSCs in umbilical cord blood (UCB) is well known, that of MPCs has been not fully evaluated. In this study, we examined the ability of UCB harvests to generate in culture cells with characteristics of MPCs. Results showed that UCB-derived mononuclear cells, when set in culture, gave rise to adherent cells, which exhibited either an osteoclast- or a mesenchymal-like phenotype. Cells with the osteoclast phenotype were multinucleated, expressed TRAP activity and antigens CD45 and CD51/CD61. In turn, cells with the mesenchymal phenotype displayed a fibroblast-like morphology and expressed several MPC-related antigens (SH2, SH3, SH4, ASMA, MAB 1470, CD13, CD29 and CD49e). Our results suggest that preterm, as compared with term, cord blood is richer in mesenchymal progenitors, similar to haematopoietic progenitors.

Adipocytes↗

PubMed2000

Biology and clinical utilization of mesenchymal progenitor cells.

Within the complex cellular arrangement found in the bone marrow stroma there exists a subset of nonhematopoietic cells referred to as mesenchymal progenitor cells (MPC). These cells can be expanded ex vivo and induced, either in vitro or in vivo, to terminally differentiate into at least seven types of cells: osteocytes, chondrocytes, adipocytes, tenocytes, myotubes, astrocytes and hematopoietic-supporting stroma. This broad multipotentiality, the feasibility to obtain MPC from bone marrow, cord and peripheral blood and their transplantability support the impact that the use of MPC will have in clinical settings. However, a number of fundamental questions about the cellular and molecular biology of MPC still need to be resolved before these cells can be used for safe and effective cell and gene therapies intended to replace, repair or enhance the physiological function of the mesenchymal and/or hematopoietic systems.

Animals↗