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PubMed1996

The phenomenology and possible mechanisms of a new experimental method for accelerating postirradiation restoration of hemopoietic stem cell potential.

Extraction of bone marrow from one or several bones immediately after irradiation, with or without subsequent incubation for a short period under suitable conditions, and subsequent reimplantation into the same organism can reduce the lethal effect of irradiation in a number of species. Extraction plus a period of incubation is referred to as the reimplantation method. The effectiveness is roughly relative to the amount of bone marrow extracted and transplanted. This effect has been demonstrated by assays of 30-45-day survival and of hemopoietic stem cell potential. The effectiveness of the reimplantation method has been tested in a dose range of 6.5 to 8.5 Gy and was found to be 1.2-1.06 in terms of dose reduction factors assayed by bone marrow row cellularity 9 days after exposure and 1.18-1.09 for survival of bone marrow colony-forming units. The favorable effect of incubating irradiated bone marrow with cycloheximide on the stem cell potential has been proven by experiments using a donor-recipient method. The positive effect of the reimplantation procedure and the partial extraction procedure on the stem cell potential in irradiated mice can be shown as soon as 2 h after exposure and the procedures. The results suggest that ther exist some reserves that can be stimulated to accelerate hemopoietic restoration in a heavily irradiated organism. The recruitment of these reserves seems to be related to the response of the structures producing cytokines after lethal irradiation. In addition, repair processes may be involved in the rescue of lethally irradiated hemopoietic stem cells.

Animals↗
PubMed2000

Hemopoietic progenitor cells are sensitive targets of 2,3,7,8-tetrachlorodibenzo-p-dioxin in C57BL/6J mice.

Treatment of adult C57BL6J mice with tetrachlorodibenzo-p-dioxin (TCDD) elicits altered bone marrow hemopoietic cellular potentials and markedly reduced T-lymphoid-reconstituting activity. The latter has been hypothesized to play a role in TCDD-induced thymic atrophy. To investigate cellular targets responsible for reduced prothymocyte capacity, bone marrow cells from TCDD-treated C57BL/6J mice were assessed for hemopoietic alterations within the lineage-negative (lin-) compartment by the examination of Sca-1 and c-Kit levels. Lin- hemopoietic cells from C57BL/6J mice, treated with 30 microg/kg of TCDD, were assessed for phenotypic alterations following 24 h through 31 days. The responses of lin- cells to TCDD doses ranging from 0.3 to 30 microg/kg were also assessed at 2 days following TCDD treatment. The data reveal increases in the number of bone marrow lin- Sca-1+ c-Kit+ cells, relative to control, over 24 h through 31 days following treatment, as well as dose-dependent increases in this population when examined at 2 days. Increases in lin- Sca-1+ c-Kit- cells occurred on a more transient basis and were also dependent upon TCDD dose. These data suggest that proliferation and/or differentiation processes of hemopoietic stem cells are affected by TCDD and that these effects contribute to a reduced capacity of bone marrow to generate pro-T lymphocytes.

Animals↗
PubMed1982

Helper cell factors restore antibody responses of allogeneic bone marrow chimeras: evidence for ineffective cellular interactions.

We investigated the nature of deficient antibody responses to SRBC in stable, fully allogeneic bone marrow chimeras. No evidence for a suppressor cell-mediated mechanism was found. Chimera spleens possessed adequate numbers of antigen-reactive B cells to produce a normal antibody response. Using separated chimera cell populations and soluble helper factors, we assessed the functional capabilities of chimera B cells, T cells, and macrophages. Our data suggest that the failure of allogeneic chimeras to produce antibody is not the result of impaired B cell, T cell, or macrophage function, but rather that it is due in ineffective cellular interactions that normally result in the generation of helper factors. In vitro stimulation of chimera macrophages with LPS, and of chimera spleen cells with Con A, resulted in the release of soluble helper factors that were capable of fully restoring chimera B cell responses.

Animals↗
PubMed1983

Use of uridine rescue to enhance the antitumor selectivity of 5-fluorouracil.

We examined the ability of uridine to increase the therapeutic index of 5-fluorouracil (FUra) against C57BL/6 X DBA/2 F1 mice bearing a Day 1 B16 melanoma or L1210 leukemia. FUra (400, 600, or 800 mg/kg, i.p.) followed in 24 hr by a 5-day s.c. infusion with uridine (5 g/kg/day, s.c.) was compared with the maximum tolerated dose of FUra (200 mg/kg, i.p.) plus a 5-day infusion with 0.9% NaCl solution. High-dose FUra plus delayed infusion with uridine was more effective than FUra (200 mg/kg) in inhibiting the growth of the B16 melanoma. High-dose FUra plus uridine rescue was, however, no more effective than FUra (200 mg/kg) in increasing the survival times of mice bearing the L1210 leukemia. To see if uridine rescue from FUra toxicity correlated with effects against a sensitive normal tissue, bone marrow nucleated cellularity of normal, non-tumor-bearing mice was monitored after drug treatment. In mice treated with FUra (200 mg/kg) followed in 24 hr by a 5-day infusion with either uridine (5 g/kg/day) or 0.9% NaCl solution, there was not as great a decrease in cellularity at the nadir with uridine, and, in addition, uridine accelerated recovery as compared to 0.9% NaCl solution. Furthermore, uridine (5 g/kg/day), but not thymidine (dThd) (5 g/kg/day) or 2'-deoxyuridine (dUrd) (5 g/kg/day), had a sparing effect on the depression in bone marrow nucleated cellularity seen at the nadir on Day 4 after Fura (200 mg/kg). The specificity of uridine to rescue mice from the lethal toxicity of the related fluorinated pyrimidines, 5-fluorouridine and 5-fluoro-2'-deoxyuridine, was also examined. Mice were treated with 5-fluorouridine (250 mg/kg, i.p.) followed in 24 hr by a 5-day infusion with uridine (1, 5, or 10 g/kg/day), dThd (1, 5, or 10 g/kg/day), or dUrd (1 or 5 g/kg/day). Uridine (1, 5, or 10 g/kg/day) rescued mice from the lethal toxicity of 5-fluorouridine, whereas dThd or dUrd was ineffective. Similarly, a 5-day infusion with uridine, but not dThd or dUrd, rescued mice from the lethal toxicity of 5-fluoro-2'-deoxyuridine (1800 mg/kg, i.p.).

Animals↗
PubMed2004

[Evaluation of bone marrow biopsy and smear examinations in differential diagnosis for patients with pancytopenia by simultaneously compartive study].

To simultaneously compare and evaluate the examinations of bone marrow smear and trephine biopsy in differential diagnosis and therapeutical effect of pancytopenia patients, the differences between bone marrow smear and trephine biopsy in degree of cellularity, misdiagnosis rate and therapeutical effect for 71 patients with pancytopenia were analyzed. The results showed that the degree of cellularity in bone marrow biopsy for cytologic morphology was higher than that from the smear, but misdiagnosis rate in the biopsy was lower than that in the smear. In conclusion, bone marrow biopsy is necessary to the differential diagnosis and more valuable for evaluation of therapeutical effect and prognosis of pancytopenia patients.

Adolescent↗
PubMed2006

Recent molecular and cellular advances in pediatric bone marrow transplantation.

The field of allogeneic transplantation has made vast improvements since its inception in 1968. Improvements in supportive care have greatly improved survival. Delayed immune reconstitution, graft versus host disease, and relapse of disease still pose great obstacles. This article has highlighted novel strategies for using cellular therapy in conjunction with hematopoietic cell transplantation (HCT) that potentially may lead to improved clinical outcomes for patients undergoing HCT in the future.

DNA Virus Infections↗
PubMed2000

Hematological toxicity associated with tiazofurin-influence on erythropoiesis.

In this study hematological toxicity was analyzed after the single and repeated applications of tiazofurin (TZF). Cellularity of bone marrow, spleen and peripheral blood was examined, spanning the period of fifty days after the initial application. Analysis of hematological parameters was performed by slightly modified conventional techniques. The fraction of erythroid series was monitored during the experiment. Presented data describe kinetics of damage and recovery of hemopoietic tissue. Our results indicate that the effect of tiazofurin on cellularity of bone marrow and spleen and on erythropoiesis is reversible and dose dependent within tested dose range and therapeutic regimes. Twenty days after the application normal function of hemopoietic tissues was restored. This approach and results can be useful in defining the timing for sequencing and combination therapy with tiazofurin.

Alopecia↗
PubMed2006

Osteogenic progenitors in bone marrow aspirates from smokers and nonsmokers.

UNLABELLED: Bone marrow aspirates contain connective tissue progenitor cells which can proliferate to form cell colonies that express connective tissue phenotypes. The number of osteogenic connective tissue progenitor cells can be estimated by counting colonies that express alkaline phosphatase, an early marker of osteoblastic differentiation. Because tobacco use is associated with decreased bone mass and fracture nonunion, we tested the hypothesis that current or previous tobacco use is an independent determinant of marrow cellularity or prevalence of osteogenic connective tissue progenitor cells among marrow-derived cells. Marrow aspirates were obtained from the anterior iliac crest of 62 patients who were grouped as never smoked, past smokers, or current smokers. The number of nucleated cells per aspirate was determined. Cells were cultured for 6 days in osteogenic media. The prevalence of osteogenic connective tissue progenitor cells was determined by counting colony forming units. The area of each colony was assessed using quantitative image analysis. Cellularity of bone marrow was found to decrease with age. We observed no relationship between smoking status and marrow cellularity, colony prevalence, or colony area. This suggests that tobacco use is not associated with a change in prevalence of osteogenic connective tissue progenitor cells in bone marrow, or their intrinsic biologic capacity to undergo early osteoblastic differentiation. LEVEL OF EVIDENCE: Diagnostic Study, Level I (testing of previously developed diagnostic criteria on consecutive patients--with universally applied reference "gold" standard). See the Guidelines for Authors for a complete description of levels of evidence.

Adult↗
PubMed1981

EAE in rat bone marrow chimeras: analysis of the cellular mechanism of BN resistance.

Unlike Lewis strain, BN rats do not develop EAE when given 10 microgram GPBP + CFA. Their resistance is mediated via the MHC-linked gene Ir-EAE-. The cellular mechanism of BN resistance can be probed using bone marrow chimeras between susceptible LBNF1 strain and BN. F1 leads to BN chimeras can develop EAE when actively sensitized with GPBP + CFA, but are markedly more resistant than F1 leads to F1. By contrast, F1 leads to BN chimeras are highly susceptible to passively transferred EAE from an F1 donor. F1 rats reconstituted with BN bone marrow, i.e., BN leads to F1 chimeras, are completely resistant to EAE induced by active sensitization, but they too are susceptible to passively transferred EAE. We argue that Ir-EAE- blocks the development of T cells reactive to self myelin, and that this occurs at the level of macrophage presentation of antigen to the T cell. Suppressor mechanisms do not appear to play a major role.

Animals↗
PubMed1977

Normal human bone marrow cultures in vitro: cellular composition and maturation of the granulocytic colonies.

The analysis of single haemopoietic colonies grown in methylcellulose and in agar was performed at intervals by a cytocentrifugation method. Correlation was established between morphology of the whole colonies and their cellular content. Three main cell lines predominated: neutrophils, macrophages, eosinophils; a few colonies contained a pure population of basophil-like granulocytes. Development was followed from myeloblasts to polymorphs, both being present in most of the colonies. Cumulated results showed that (1) the proliferating compartment remained quite large till day 14, with 58% of cells in S phase, and rapidly decreased after day 16, and that (2) the polymorphs rapidly disappeared from the culture medium. Differentiation proceeded at different rates from one colony to the other, thus suggesting heterogeneity between colony forming cells (CFC). Neutrophil colonies appeared and lysed more rapidly than did eosinophil colonies. Macrophages arose from large immature cells with many promyelocyte features; such cells were present in mixed colonies, containing both neutrophils and macrophages. It is very likely that granulopoiesis results from the development of distinct committed CFC. This work was carried out using normal human bone marrow and may be a useful tool for studying pathological material in the future.

Adult↗
PubMed2006

Comparative analysis of mesenchymal stem cells from bone marrow, umbilical cord blood, or adipose tissue.

Mesenchymal stem cells (MSCs) represent a promising tool for new clinical concepts in supporting cellular therapy. Bone marrow (BM) was the first source reported to contain MSCs. However, for clinical use, BM may be detrimental due to the highly invasive donation procedure and the decline in MSC number and differentiation potential with increasing age. More recently, umbilical cord blood (UCB), attainable by a less invasive method, was introduced as an alternative source for MSCs. Another promising source is adipose tissue (AT). We compared MSCs derived from these sources regarding morphology, the success rate of isolating MSCs, colony frequency, expansion potential, multiple differentiation capacity, and immune phenotype. No significant differences concerning the morphology and immune phenotype of the MSCs derived from these sources were obvious. Differences could be observed concerning the success rate of isolating MSCs, which was 100% for BM and AT, but only 63% for UCB. The colony frequency was lowest in UCB, whereas it was highest in AT. However, UCB-MSCs could be cultured longest and showed the highest proliferation capacity, whereas BM-MSCs possessed the shortest culture period and the lowest proliferation capacity. Most strikingly, UCB-MSCs showed no adipogenic differentiation capacity, in contrast to BM- and AT-MSCs. Both UCB and AT are attractive alternatives to BM in isolating MSC: AT as it contains MSCs at the highest frequency and UCB as it seems to be expandable to higher numbers.

Adipose Tissue↗
PubMed2001

Enforced expression of GATA-3 severely reduces human thymic cellularity.

Following bone marrow transplantation, patients often suffer from immune incompetence by reduced or late T cell development. Moreover, adult bone marrow stem cells have a lower capacity to generate T cells compared with fetal liver- and umbilical cord blood-derived progenitors. Therefore, enhancing thymic-dependent T cell generation might hold great therapeutic potential. GATA-3 is a transcription factor that is essential in T cell development. In this study we examined the therapeutic potential of GATA-3 to enhance T cell generation by overexpressing GATA-3 in T cell progenitors followed by fetal thymic organ culture (FTOC). We observed that early during FTOC, there was an enhanced differentiation toward the double positive stage of T cell development. From day 10 of FTOC, however, overexpression of GATA-3 induced a severe reduction in thymic cellularity, which probably correlates with the absence of a functional TCR-beta chain. We further show that the frequency of apoptosis was increased in GATA-3-transduced thymocytes. Despite the absence of a functional TCR-beta chain, GATA-3 transduced progenitors were able to differentiate into CD8beta(+) double positive thymocytes. This study shows that a strictly regulated expression of GATA-3 is essential for normal T cell development and this puts severe restrictions on the potential therapeutic use of continuously overexpressed GATA-3.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1985

Verapamil potentiation of melphalan cytotoxicity and cellular uptake in murine fibrosarcoma and bone marrow.

Growth delay by melphalan of two fibrosarcomas in CBA mice was prolonged by intraperitoneal (i.p.) verapamil, 10 mg kg-1. Verapamil also increased the area under the blood concentration time curve and the gastrointestinal toxicity of melphalan. Verapamil promoted melphalan cytotoxicity to murine bone marrow both in vivo, by CFU-S assay, and in vitro, by CFU-GM assay. In 1 microgram ml-1 [14C]-melphalan, verapamil (10 micrograms ml-1) increased by 1.5 times the [14C]-melphalan accumulation by murine bone marrow, reversibly and independently of external calcium. Efflux of [14C]-melphalan from murine bone marrow was retarded by verapamil. Verapamil increased [14C]-melphalan uptake by disaggregated fibrosarcoma cells but had no effect on melphalan accumulation and cytotoxicity in human bone marrow. Although verapamil affected melphalan pharmacokinetics, enhancement of cellular melphalan uptake by verapamil in murine fibrosarcoma and bone marrow appeared to account for much of the increase in melphalan cytotoxicity. The lack of potentiation of melphalan by verapamil in human marrow suggests differences in melphalan transport or in verapamil membrane interactions in mouse and man.

Animals↗
PubMed1987

Detection of malignant cells in histologically normal bone marrow using culture techniques.

Cellular material retained on screens used to filter aspirated bone marrow for future autologous marrow transplantation was studied using long-term culture techniques in 20 consecutive patients. All patients had marrow aspirate and biopsy specimens that were normal histologically. Cultures from five patients grew malignant cells similar to those of the known underlying malignancy. Two types of culture methods were used in these studies. Method I consisted of a long-term bone marrow culture system which predominantly favors adherent cells, and Method II consisted of a suspension type culture system favoring expansion of mononuclear cell types. These findings suggest that tumor cells are reinfused more often at the time of autologous bone marrow transplantation than has been previously suspected. Although the clinical significance of these findings is not known, it is clear that culture techniques combined with special stains and molecular probing will allow the improved detection of occult tumor cells in bone marrow from patients undergoing autologous marrow transplantation. These observations emphasize the need for a comprehensive study of histologically normal autologous marrow using culture techniques to determine the frequency of occult involvement by viable malignant cells and the clinical implications of these findings.

Adult↗
PubMed2004

Multifactorial risk analysis of bone marrow histiocytic hyperplasia with hemophagocytosis in critically ill medical patients--a postmortem clinicopathologic analysis.

OBJECTIVE: Systematic studies of the prevalence and risk factors of histiocytic hyperplasia with hemophagocytosis (HHH) in critically ill patients are lacking. The aim of our study was a) to determine the frequency and intensity of HHH in the bone marrow of patients who died on the medical intensive care unit; b) to analyze morphologic bone marrow changes; and c) to identify possible risk factors and their interactions in the pathogenesis of HHH. DESIGN: A retrospective observational analysis of clinical data and autopsy findings including histologic and immunohistological analysis of bone marrow to characterize cellularity, siderosis, hemophagocytosis, and T-cell infiltrates. SETTING: The medical intensive care unit of a university hospital. PATIENTS: Patients were 107 consecutive patients who died and underwent autopsy. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: HHH was identified in 69 of the 107 patients (64.5%). Moderate to severe HHH was present in 35 of the 107 bone marrows. Univariate risk factor analysis showed that HHH was associated with various intrinsic and extrinsic factors. However, multivariate analysis identified the intensity of therapeutic interventions--represented by the Therapeutic Intervention Scoring System--as the only positive, and cardiovascular disease as the only significant negative, predictor of HHH (p <.05). Routine laboratory tests were of no value in predicting the presence of HHH. The intensity of HHH correlated significantly with siderosis and T-cell infiltrates (p <.05) but not with bone marrow cellularity. CONCLUSIONS: HHH is common in medical intensive care unit nonsurvivors. Treatment intensity and a noncardiovascular cause of death are predictors of HHH. Sepsis and blood transfusion may have a synergistic effect on the triggering of HHH. HHH in bone marrow is associated with enhanced T-cell infiltrates, suggesting that T cells may play an important role in its mediation.

Aged↗
PubMed1976

Cellular composition of the bone marrow in the chicken. I. Identification of cells.

Incorporation of Fe55 in vivo was used for verifying on radioautographs the identity of chicken bone marrow cells that are in the process of hemesyntheses. Under the experimental conditions all labeled cells may be considered to be linked with erythroid differentiation. They were classified into five maturational stages according to their morphology and capacity for DNA synthesis. Granulocytes were identified by the presence of specific granules. All mononuclear cells were classified as lymphocytes which had a pachychromatic nucleus, a high nucleocytoplasmic ratio, lacked the capacity for DNA synthesis, and resembled small lymphocytes of the bursa, spleen and bone marrow that bound, in vitro, anti-chicken gamma globulins labeled with I125. Radioautography with H3TdR was used to identify proliferating and non-proliferating members of each cell population.

Animals↗