This study reports the development of an assay, the Pre-colony-forming unit (CFU) assay, which detects human hematopoietic precursors. The Pre-CFU assay is based on the observation that precursors to CFU-granulocyte-macrophage (CFU-GM) that are undetectable in clonogenic assays differentiate into CFU-GM preferentially following treatment in suspension culture with recombinant human interleukin-...

We have investigated the effects of in vivo treatment with flt3 ligand (FL) on murine hematopoiesis, including mobilization of progenitors into the peripheral blood (PB). Mice were injected once daily with 10 micrograms recombinant human FL for 15 days. On days 3, 5, 8, 10, 15, and 22, mice were killed and analyzed for the number of leukocytes and colony-forming units (CFU) in bone marrow (BM),...

Low-dose actinomycin D (Acto) selectively suppresses murine erythropoiesis without decreasing erythropoietin (Ep) production. We used the plasma clot system to determine the stage of erythroid differentiation at which this inhibition occurs. Late erythroid precursors, CFU-E, and less differentiated committed erythroid stem cells, BFU-E, were assayed in CF1 mice given Acto 75-82 microgram/kg/day...

When introduced intranasally, P. cepacia AC1100 (approximately 10(8) CFU/animal) and P. aeruginosa AC869 (approximately 10(3) CFU/animal) were readily cleared from the mouse. However, a approximately 10(7)-CFU dose of AC869 persisted for 14 days. Strain AC869 had a 50% lethal dose of 2.7 x 10(7) CFU. Slight morbidity occurred in animals treated with approximately 10(7) CFU of AC869 or approxima...

background and aims. bacterial contamination of dental unit water supplies (duws) has attracted a lot of attention in recent years due to the emergence of serious infections in susceptible dental patients. the aim of the present study was to evaluate the presence of gram-negative bacterial contamination in duws at tabriz university of medical sciences faculty of dentistry. materials and methods...

UNLABELLED We describe the effects of 4-hydroperoxycyclophosphamide (4-HC) on the hematopoietic and stromal elements of human bone marrow. Marrow cells were exposed to 4-HC and then assayed for mixed (CFU-Mix), erythroid (BFU-E), granulomonocytic (CFU-GM), and marrow fibroblast (CFU-F) colony-forming cells and studied in the long-term marrow culture (LTMC) system. The inhibition of colony forma...

Hematopoiesis is thought to be modulated by interactions of progenitor cells with hematopoietic growth factors. We have shown that colony-forming units-spleen (CFU-S) and repopulating stem cells require interleukin-3 (IL-3) to survive in vitro, and that CFU-S number and long-term repopulating ability can be increased by culture in the combination of IL-3 and IL-6. In this report, we describe th...

The effects of recombinant human tumor necrosis factor (rH-TNF) on the colony growth of human leukemia progenitor cells (L-CFU), granulocyte-macrophage progenitor cells (CFU-GM), and erythroid progenitor cells (BFU-E) were studied. L-CFU was assayed with leukemia cells obtained from patients with acute myelogenous leukemia. CFU-GM and BFU-E were assayed with bone marrow cells obtained from hema...