In vitro cell cycle dynamics of primitive hematopoietic cells from human umbilical cord blood.

The goal of the present study was to investigate the specific way in which recombinant stimulatory cytokines modulate the cell cycle dynamics of primitive hematopoietic cells in vitro. A human cord blood-derived cell population, enriched for CD34(+) Lin(-) cells, was obtained by negative selection and cultured in liquid cultures, in the absence or presence of recombinant stimulatory cytokines. The proportion of cells in each phase of the cell cycle, as well as the expression of cyclin D3, cyclin-dependent kinase-4 (cdk4), p16, p21 and p27, was determined at different time points.

Cell cycle differences in vitro between primitive hematopoietic cell populations from adult and umbilical cord blood.

Lineage-negative (Lin(-)) cell populations, obtained by negative selection from umbilical cord blood (UCB) and adult mobilized peripheral blood (aMPB), were cultured in serum-free liquid cultures supplemented with a mixture of seven stimulatory cytokines. On specific days, proliferation potential was assessed and cell cycle status was determined by DNA content. Expression of the cell cycle regulators cyclin D3 (cD3), cyclin-dependent kinase 4 (cdk4), p21(cip1/waf1) (p21), and p27(kip1) (p27) was also determined.

Low serum levels of dehydroepiandrosterone and cortisol in human diffuse cutaneous leishmaniasis by Leishmania mexicana.

Low levels of dehydroepiandrosterone (DHEA) and cortisol hormones produced by the suprarenal cortex have been associated with diseases involving chronic inflammation, low interferon (IFN)-gamma, and high interleukin (IL)-6. Diffuse cutaneous leishmaniasis (DL), a long-lasting intracellular parasitic infectious disease, can spread unknown levels of DHEA and cortisol. Serum concentrations of both were measured in 5 patients with DL, in 15 patients with localized lesions produced by Leishmania (LL), and in 20 healthy volunteers.