Number Of Nucleated Cells In Bone Marrow Research Articles

Characteristics of Bone Marrow Progenitor Cells of C57BL/6N Mice after 30-Day Hindlimb Suspension and 12-Hour Readaptation to Support Loading

The functional status of bone marrow (BM) progenitor cells, which provide hematopoiesis and homeostasis of bone tissue, determines many processes which take a place in spaceflight (SF) and subsequent recovery to gravity. It is known that SF factors and simulation of their effects do irreversible damage to the pool of hematopoietic and stromal progenitor cells. Meanwhile, changes in the functional activity of BM progenitor cells after simulation of SF effects were more pronounced than in the case of a real SF. The aim of the study was to examine processes of recovery of the functional activity of BM progenitor cells during readaptaion to loading after 30-day hindlimb suspension. Studies were performed on three groups of male mice: vivarium control, suspension, and readaptation. The following characteristics were monitored: number of nucleated BM cells, immunophenotype, proliferative activity of stromal BM cells, number of hematopoietic colony-forming units (CFU), CFUs of fibroblasts, and differentiating capabilities of BM hematopoietic and stromal precursors. Hindlimb suspension resulted in decreased number of fibroblast and hematopoietic CFU, inhibition of spontaneous osteodifferentiation of stromal progenitors and decreased expression of stromal markers. The readaptaion period was accompanied with restoration of the functional activity of stromal progenitors, while complete recovery of hematopoiesis was not observed.

Decorporating efficacy of catecholaminocarboxylate chelating agents for thorium-234 and protective effects on associated radiation injury

The aim was to identify the decorporation and anti-oxidation efficacy of prompt and delayed consecutive administration of the catecholicpolyaminopolycarboxylate ligands 9501 and 7601 for radiothorium in vivo. The chelating agents 9501 or 7601 were administered intramuscularly to ICR mice 3 min or 3 days after intraperitoneal injection of 30 MBq kg – 1 234Th-citrate for 3 consecutive days. The animals were killed 4 or 5 days after administration of the chelating agents, respectively. The 234Th radioactivity in the whole-body and its retention in liver and skeleton were determined. Malondialdehyde (MDA) production, as an index of 234Th-induced lipid peroxidation in bone marrow and liver, was assayed and the number of bone marrow nucleated cells (NBMNC) were counted. The pathological changes of bone marrow and liver tissue were observed. CaNa3-diethylenetriaminepentaacetate (DTPA) and vitamin E were used as controls. The competitive ability of 9501 and 7601 to mobilize thorium with bovine serum albumin (BSA) was studied. Their inhibitory effect on superoxide anion radicals was measured by electron spin resonance. When promptly injected, 9501 or 7601 were superior to CaNa3-DTPA for reducing 234Th retention in mouse. Their different bioactivity for decorporation of 234Th was consistent with their competitive ability to mobilize thorium with BSA. Although the removal effectiveness of 9501 and 7601, given by delayed injection, was lower than that of the prompt administration, they could inhibit 234Th-induced lipid peroxidation. This caused significant reductions of MDA content in bone marrow and liver and markedly ameliorated histological changes to bone marrow and liver tissue in 234Th-treated mice. Their protective effects were better than CaNa3-DTPA and vitamin E. 9501 and 7601 could directly scavenge . Their effects as scavengers were very significant. The chelating agents 9501 and 7601 are able to remove thorium as effectively as other commonly used agents like CaNa3-DTPA and reduce radiation dose. In addition, these agents have anti-oxidative action reducing both cell killing in the bone marrow and malondialdehyde levels, a measure of lipid peroxidation, in the bone marrow and liver. The protection from internally deposited radioactive material was predictable by the chelators' competitive ability to chelate thorium from BSA and their ability to act as an oxygen free-radical scavenger. The duel effect of reducing radiation dose and response could be important in reducing the risk from internally deposited gamma radionuclides.

Effects of short-term administration of G-CSF (filgrastim) on bone marrow progenitor cells: analysis of serial marrow samples from normal donors.

To determine the effect of G-CSF administration on both the total number of CD34+ cells and the primitive CD34+ subsets in bone marrow (BM), we have analyzed BM samples serially obtained from 10 normal donors in steady-state and during G-CSF treatment. Filgrastim was administered subcutaneously at a dosage of 10 microg/kg/day (n = 7) or 10 microg/kg/12 h (n = 3) for 4 consecutive days. Peripheral blood sampling and BM aspirates were performed on day 1 (just before G-CSF administration), day 3 (after 2 days of G-CSF), and day 5 (after 4 days of G-CSF). During G-CSF administration, a significant increase in the total number of BM nucleated cells was observed. The percentage (range) of CD34+ cells decreased in BM from a median of 0.88 (0.47-1.44) on day 1 to 0.57 (0.32-1.87), and to 0.42 (0.16-0.87) on days 3 and 5, respectively. We observed a slight increase in the total number of BM CD34+ cells on day 3 (0.66 x 10(9)/l (0.13-0.77)), and a decrease on day 5 (0.23 x 10(9)/l (0.06-1.23)) as compared with steady-state (0.40 x 10(9)/l (0.06-1.68)). The proportion of primitive BM hematopoietic progenitor cells (CD34+CD38-, CD34+HLA-DR-, CD34+CD117-) decreased during G-CSF administration. In parallel, a significant increase in the total number of CD34+ cells in peripheral blood was observed, achieving the maximum value on day 5. These results suggest that in normal subjects the administration of G-CSF for 5 days may reduce the number of progenitor cells in BM, particularly the most primitive ones.

A morphological analysis of the short-term effects of benzene on the development of the hematological cells in the bone marrow of mice and the effects of interleukin-1 alpha on the process.

Chronic exposure of humans to benzene (BZ), a widely used industrial chemical and a ubiquitous environmental pollutant, causes aplastic anemia and acute myeloid leukemia. The purpose of the studies reported here was to determine whether the observed depression of bone marrow (BM) cellularity in mice administered benzene was reflected in a suppression of development of all of the hematopoietic lineages and to confirm the ability of interleukin-1 alpha (IL-1 alpha) to prevent BZ-induced BM cell depression. We report that BZ, administered twice per day for 2 days to C57B1/6J mice at a dose of 600 mg/kg body weight, caused a significant depression of the total number of nucleated BM cells per femur when measured on day 3. The observed depression reflects a complex situation that represents the net effect of a decrease in the total number of cells of the lymphocytic and erythroid lineages, along with an increase in the number of intermediate and terminally differentiated cells of the granulocytic lineage. An experiment to monitor the effects of BZ over a 7-day period showed a progressive depressive effect on the lymphocytes and an initial depression of the erythroid cells at day 3 that remained constant until day 7. Conversely, the numbers of intermediate and terminally differentiated granulocytes progressively increased over the 7 days. The BM appeared to recover from the depressive effects of BZ immediately upon cessation of exposure, as the number of nucleated BM cells began to rise by day 5 and was equal to that of the control group by day 7. The results expand our earlier finding (Renz and Kalf 1991) that the overall depression of BM cellularity occurs because of an inability of the stromal fibroblast to produce colony-stimulating factors essential for stem and progenitor cell survival. This results from inhibition by the BZ metabolite, hydroquinone (HQ), of the processing of pre-IL-1 alpha to the mature cytokine.(ABSTRACT TRUNCATED AT 250 WORDS)