Cell Content Of Bone Marrow Research Articles

Effect of intraarticular injection of chondroitin sulfate into synovial joint elements in an experiment

Objective: to study morphological and morphometric changes in the epiphysis bone in a rat during the intra-articular injection of chondroitin sulfate (CS). Mаteriаl аnd methods. The object of the study was the knee joints of 36 Wistar rats. CS injections at a dose of 0.05 ml were performed once a week into one of the knee joints (experimental joint), and isotonic NaCl solution at the same volume was injected into the opposite joint (control joint). The animals in the number of 12 units were withdrawn from the experiment on the 7th, 14th, and 21st days, which corresponded to one week after one-, two-and three-fold intra-articular injections of HC and 0.9 % NaCl. The isolated knee joints were placed in a decalcifying liquid, then were fixed in 10% neutral buffered formalin. 4 micron histological sections were stained with hematoxylin and eosin. The morphometric analysis assessed the thickness of hyaline articular cartilage, the thickness of the epiphysis growth zone cartilage, and the cell content of the subchondral bone. Results. The study of the thickness of the articular cartilage, the growth zone of epiphyseal cartilage and the cellular composition of the subchondral bone has showed a statistically significant dynamic increase in these indicators after the 2nd and 3rd intra-articular injections of CS. The assessment of the thickness of the articular cartilage on the 21st day found some statistically significant differences between the experimental and control groups (p < 0.0001), the thickness of the epiphyseal cartilage had increased significantly by that time (p < 0.0001), and the cell content of bone marrow showed statistically significant differences (p = 0.002). Conclusion. The obtained data testify to a pronounced regenerative effect of CS, injected intra-articularly into articular cartilage.

Local chemical sympathectomy of rat bone marrow and its effect on marrow cell composition.

Existing experimental studies of the effect of sympathetic nerve fibers on bone marrow cells are based on the systemic administration of neurotoxic 6-hydroxydopamine. The method of global chemical sympathectomy has some serious disadvantages and could lead to questionable results. We describe a new method of local chemical sympathectomy of rat femoral bone marrow using guanethidine (Ismelin) delivery using an osmotic mini pump. Local guanethidine treatment for 14days led to complete elimination of sympathetic fibers in femoral bone marrow in contrast to bone marrow of contralateral or naïve femurs. Ablation of sympathetic fibers was associated with a loss of rat endothelial cell marker (RECA) indicating immunophenotype changes in blood vessel endothelial cells, but no significant effect of guanethidine was found on the survival of endothelial cells and mesenchymal stem cells in vitro. Moreover, local guanethidine treatment also elicited a significant reduction of Nestin+/SDF1+ mesenchymal stem cells and c-Kit+/CD90+ hematopoietic stem cells in femoral bone marrow. Tissue-specific chemical sympathectomy of rat bone marrow by guanethidine overcomes some of the drawbacks of systemic administration of neurotoxic compounds like 6-hydroxydopamine and delivers unequivocal evidence on the effects of sympathetic innervation on the cell content of bone marrow.

Abstract 12445: A Detailed Analysis of Peripheral Blood Cytokines 2-3 weeks After Acute Myocardial Infarction: IL-6-Related Impairment of Bone Marrow Function

Background: Intracoronary infusion of bone marrow (BM) mononuclear cells (BM-MNCs) late after acute myocardial infarction (AMI) has shown no improvement in global or regional left ventricular (LV) function (LateTIME and SWISS-AMI). Studies in experimental AMI models suggest a possible cytokine-related depression of progenitor cell function. Furthermore, BM cell content is correlated with the LV functional response. Accordingly, we hypothesize that inflammatory cytokines associated with the late phase of AMI may impair BM function and alter progenitor cell subsets. Method: Patients with previous AMI (n=87) were recruited in a multicenter cell therapy trial by the Cardiovascular Cell Therapy Research Network (CCTRN LateTIME, NCT00684060). BM and peripheral blood (PB) were collected 2-3 weeks after AMI and examined for cell phenotypes and progenitor capacities as well as PB inflammatory and angiogenic cytokines in a core laboratory. Multiple regression analyses were conducted and correlations between cytokine levels and cell phenotypes, cell functions, and post-MI cardiac function were determined. BM from healthy donors, handled in the same manner, was used as a reference. Result: Of 26 cytokines analyzed, IL-6 showed a negative correlation with ECFC colony maximum in BM (estimate±SE (SEE) -0.13±0.04 P=0.007, multivariableR2: 0.59) and Healthy BM showed decreased ECFC colony outgrowth in the presence of IL-6 (P <0.05), in a dose-dependent manner. PDGF-BB positively correlated with CFU-EC colony maximum in BM (SEE 0.006± 0.002, P=0.023, R2: 0.22), MSC colony maximum in BM (SEE 0.006±0.002, P=0.023, R2: 0.17) and MSC colony maximum in PB (SSE 0.018±0.005, P=0.00005, R2:0.24). No significant correlations were found between cardiac function after AMI and PB cytokine levels. Conclusions: At 2-3 weeks after AMI, PB levels of the angiogenic cytokine, PDGF-BB and the pro-inflammatory cytokine, IL-6, were associated with BM cell phenotype and function. IL-6 has the potential to impair endothelial progenitor cell capacity; inhibiting IL-6 may be a target for improving the regenerative capacity of BM cells after AMI.

Clopidogrel Modulates LPS-Induced Systemic Inflammation Through a P2Y12 receptor Independent Pathway

Thienopyridines are a class of anti-platelet drugs that are metabolized in the liver to several metabolites of which only one active metabolite can irreversibly antagonize the platelet P2Y12 receptor. Possible effects of these drugs and the role of activated platelets in inflammatory responses have previously been investigated in a variety of animal models, demonstrating that thienopyridines could alter inflammation. Interestingly, P2Y12 may also be expressed in other cells of the immune system, indicating that the effects of the drug could directly target other cells rather than platelets. Furthermore, neutrophil functions could be inhibited by the in vitro generated metabolites of a thienopyridine such as prasugrel, although these cells did not express P2Y12 receptor. Hence, it is not clear whether thienopyridine effects are caused only by the P2Y12antagonism or whether also off-target effects of other metabolites intervene.To address this question, we investigated P2Y12 deficient mice (KO) during a LPS-induced model of systemic inflammation (3mg/kg for 4 days). In addition, we also treated these KO mice with a thienopyridine drug, clopidogrel (loading dose: 30kg/kg; maintenance dose: 10kg/kg). We investigated possible changes in spleen and bone marrow cell content and lung injury.Data show that spleen cell content, in terms of neutrophil accumulation, CD11b and CD25 expression, was altered in LPS-treated P2Y12 KO mice compared with the wild-type (WT) counterpart (Fig. 1). Interestingly, clopidogrel treatments could influence changes in cell content and receptor expression in LPS-treated deficient mice as well as in WT (Fig. 1). [Display omitted] Our results indicate that, also in the bone marrow, the lack of the receptor shows an increase in cell content and CD11b and CD25 expression (Fig. 2), suggesting a role for P2Y12 in regulation of bone marrow cellular composition during inflammation. It is interesting to notice that cell content observed in both spleen (Fig. 1) and bone marrow (Fig. 2) of healthy KO mice was different from the data obtained in healthy WT, suggesting that this receptor may be involved in the physiological cell composition of these organs. Furthermore, clopidogrel treatment could again alter KO mice response to inflammation, indicating that this drug may also have P2Y12 independent effects (Fig. 2). Finally, LPS-induced injury was more severe in the lungs of KO mice, compared to WT, since an increase in myeloperoxidase (MPO) expression was noted in LPS-exposed KO lungs compared with LPS-exposed WT (Fig. 3). [Display omitted] [Display omitted] In conclusion, our study shows that P2Y12 receptor deficiency could enhance LPS-induced inflammation. This finding is in contrast with some previous data presenting clopidogrel treatments as playing a protective role. The observed disparity suggests that the lack of P2Y12 receptor may have different implications in different stages of inflammation. Furthermore, our findings underline that P2Y12 receptor could be involved in regulation of cellular composition even in healthy animals, thus modifying their responsiveness to inflammation. Finally, since clopidogrel treatment could alter KO mice, this drug could have P2Y12 independent effects that need to be further investigated. Disclosures:No relevant conflicts of interest to declare.

CD2 antigen expression on leukemic cells as a predictor of event-free survival after chemotherapy for T-lineage acute lymphoblastic leukemia: a Children's Cancer Group study

We examined the prognostic impact of CD2 antigen expression for 651 patients with T-lineage acute lymphoblastic leukemia (ALL), who were enrolled in front-line Childrens Cancer Group treatment studies between 1983 and 1994. There was a statistically significant correlation between the CD2 antigen positive leukemic cell content of bone marrow and probability of remaining in bone marrow remission, as well as overall event-free survival (EFS) (P = .0003 and P = .002, log-rank tests for linear trend). When compared with patients with the highest CD2 expression level (> 75% positivity), the life table relative event rate (RER) was 1.22 for patients with intermediate range CD2 expression level (30% to 75% positivity) and 1.81 for “CD2-negative” patients (< 30% positivity). At 6 years postdiagnosis, the EFS estimates for the three CD2 expression groups (low positivity to high positivity) were 52.8%, 65.5%, and 71.9%, respectively. CD2 expression remained a significant predictor of EFS after adjustment for the effects of other covariates by multivariate regression, with a RER of 1.47 for CD2- negative patients (P = .04). Analysis of T-lineage ALL patients shows a significant separation in EFS after adjustment for the National Cancer Institute (NCI) age and white blood cell (WBC) criteria for standard and high-risk ALL (P = .002, RER = 1.67). The determination of CD2 expression on leukemic cells helped identify patients with the better and poorer prognoses in both of these risk group subsets. For standard risk T-lineage ALL, CD2-negative patients had a worse outcome (P = .0007, RER = 2.92) with an estimated 5-year EFS of 55.9% as compared with 78.3% for the CD2-positive patients. Thus, CD2 negativity in standard risk T-lineage ALL identified a group of patients who had a worse outcome than high-risk T-lineage ALL patients who were CD2 positive. The percentage of CD2 antigen positive leukemic cells from T- lineage ALL patients is a powerful predictor of EFS after chemotherapy. This prognostic relationship is the first instance in which a biological marker in T-lineage ALL has been unequivocally linked to treatment outcome.

CD2 Antigen Expression on Leukemic Cells as a Predictor of Event-Free Survival After Chemotherapy for T-Lineage Acute Lymphoblastic Leukemia: A Children’s Cancer Group Study

AbstractWe examined the prognostic impact of CD2 antigen expression for 651 patients with T-lineage acute lymphoblastic leukemia (ALL), who were enrolled in front-line Childrens Cancer Group treatment studies between 1983 and 1994. There was a statistically significant correlation between the CD2 antigen positive leukemic cell content of bone marrow and probability of remaining in bone marrow remission, as well as overall event-free survival (EFS) (P = .0003 and P = .002, log-rank tests for linear trend). When compared with patients with the highest CD2 expression level (>75% positivity), the life table relative event rate (RER) was 1.22 for patients with intermediate range CD2 expression level (30% to 75% positivity) and 1.81 for “CD2-negative” patients (<30% positivity). At 6 years postdiagnosis, the EFS estimates for the three CD2 expression groups (low positivity to high positivity) were 52.8%, 65.5%, and 71.9%, respectively. CD2 expression remained a significant predictor of EFS after adjustment for the effects of other covariates by multivariate regression, with a RER of 1.47 for CD2-negative patients (P = .04). Analysts of T-lineage ALL patients shows a significant separation in EFS after adjustment for the National Cancer Institute (NCI) age and white blood cell (WBC) criteria for standard and high-risk ALL (P = .002, RER = 1.67). The determination of CD2 expression on leukemic cells helped identify patients with the better and poorer prognoses in both of these risk group subsets. For standard risk T-lineage ALL, CD2-negative patients had a worse outcome (P = .0007, RER = 2.92) with an estimated 5-year EFS of 55.9% as compared with 78.3% for the CD2-positive patients. Thus, CD2 negativity in standard risk T-lineage ALL identified a group of patients who had a worse outcome than high-risk T-lineage ALL patients who were CD2 positive. The percentage of CD2 antigen positive leukemic cells from T-lineage ALL patients is a powerful predictor of EFS after chemotherapy. This prognostic relationship is the first instance in which a biological marker in T-lineage ALL has been unequivocally linked to treatment outcome.

Bone marrow cell content and osteoclasts in crista biopsies.

The bone marrow cell content was investigated by counting the percentage of cells in the areas between the trabeculae in crista biopsies. There was a decrease in the percentage of cells in bone marrow in osteoporotic women compared with our normal material. In patients undergoing haemodialysis there was a positive correlation between bone marrow cell content and osteoclasts, which could indicate a possible connection between osteoclasts and bone marrow cells.

Initial Investigations of the Changes in the Stem Cell Compartment of Murine Bone Marrow During Post-Hypoxic Polycythemia

Abstract As assessed by its spleen colony-forming ability, the stem cell content of bone marrow from mice recovering from hypoxia increases with the duration of erythropoietic depression, and is directly proportional to the number of marrow lymphocytes.

Studies of the Reticuloendothelial Mass and Sequestering Function of Rat Bone Marrow

Abstract Quantitative studies were made in rats of the total reticuloendothelial cell content of bone marrow and of the ability of marrow to sequester antibody-treated red cells, immature red cells and carbon particles. Although normal marrow played a relatively minor role in clearing cells and particles from the blood stream, its clearing activity increased markedly when the marrow was depleted of its blood-forming cells. The greatly enhanced ability of hypoplastic marrow to trap immature red cells suggests that this may be a homeostatic mechanism for repopulating the depleted marrow. Carbon blockade resulted in decreased liver and spleen uptake of sensitized red cells, but enhanced the marrow uptake. This suggests that marrow sequestration of cells, in contrast to that in the liver and spleen sequestration, is not affected by phagocytic activity. In their functions and reactions the RE cells of the marrow usually acted in parallel with those of the liver and reciprocally with those of the spleen.

Fat and cell content of bone marrow in hyper- and hypothyroidism

Fat and cell content of bone marrow in hyper- and hypothyroidism