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Results for “bone marrow cellularity”

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PubMed1993

Bone marrow after autologous blood stem cell transplantation and total body irradiation: magnetic resonance and chemical shift imaging.

Magnetic resonance studies of the lumbar, pelvic, and femoral bone marrow were performed in 10 patients after autologous blood stem cell transplantation, including total body irradiation and myeloablative chemotherapy. The posttreatment interval varied between 2 and 6 yr. The appearance on T1-weighted images and the quantitative data obtained from chemical shift imaging (relative fat signal) were compared to 10 age-matched healthy volunteers. The classification of the T1-weighted images yielded no significant differences between the two groups. Chemical shift imaging by determination of the relative fat signal was able to detect a significant fatty replacement of the patients' lumbar (p < .002) and pelvic marrow (p < .01), showing the clinically inapparent decreased cellularity of the bone marrow. This difference did not change within the interval of 2-6 yr after transplantation.

Acute Disease↗

PubMedDate not supplied

Functional outcome of bone marrow stem cells: mononuclear versus mesenchymal stem cells after cellular therapy in myocardial scar in Wistar rats.

Experimental studies have suggested that a bone marrow stem cell transplant into the heart produces a favorable impact on tissue perfusion, yielding a new perspective on myocardial regeneration. Studies in human beings have demonstrated an improved clinical and functional cardiac state, which has been explained mainly by the angiogenic potential of the stem cells. Our objective was to compare the functional outcome of mononuclear stem (MoSC) and mesenchymal stem (MeSC) cell therapy after myocardium infarction in rats. Forty-two rats with myocardial infarctions underwent autologous transplantation of MoSC and MeSC in animals with ejection fractions lower than 40%. The functional analysis was performed using echocardiography at baseline and at 1 month after direct injection into the ventricular wall using: 5 x 10(6) MoSC (n = 08) or 2.5 x 10(6) MeSC (n = 13) or medium controls (n = 21). Statistical significance was accepted when P < .05. Intragroup comparisons of baseline versus 1-month follow-up were performed with paired t tests. Kruskal-Wallis was used as appropriate. There was a difference in baseline left ventricular ejection fraction (LVEF) and left ventricular-end dyastolic volume between all groups. After 1 month, LVEF decreased in the control group but remained unchanged in MoSC and MeSC groups. In all groups we observed myocardial remodeling. In conclusion, we have not demonstrated functional effectiveness with either MoSC or MeSC cell type, but potentially improved myocardial perfusion needs to be analyzed.

Animals↗

PubMed1989

[Possibilities of using the peroxidase-antiperoxidase method for phenotyping cells in bone marrow and blood smears].

This method (PAP method) may be used for determining the cellular immunologic phenotype in bone marrow and blood smears, of the blast elements in hemoblastosis patients among other things. The panels of monoclonal antibodies for the PAP method should be selected by their preliminary testing in the PAP method and in immunofluorescence test. PAP method with monoclonal antibodies may be used in both hematologic and cytologic laboratories for determining the histogenetic appurtenance of the cells in dubious diagnostic cases.

Blood Cells↗

PubMed2000

Radioprotection of haemopoietic stem cells by a single injection of bacterial lysate - IRS-19 administered to mice before or after irradiation.

Data in this report describes the effect of a single injection of bacterial lysate IRS-19 prior to irradiation of C57Bl/6 mice on recovery of colony-forming cells (CFC) after sublethal and lethal doses of radiation. The injection of IRS-19 promoted an earlier recovery of colony-forming cells in the bone marrow and spleen. For example, 5 and 9 days after 7.5 Gy irradiation, the number of CFU-S per femur was approximately 1.7-2.3-fold higher in IRS-19-injected mice than in saline-injected mice. Also, pretreatment of mice with IRS-19 induced an increase in the number of endogenous haemopoietic stem cells (endoCFU-S). In the postradiation period (5-21 days) significantly increased bone marrow and spleen cellularity and accelerated myelopoietic regeneration (committed progenitor granulocyte-macrophage-colony-forming cells, GM-CFC) in the bone marrow and spleen compared with saline-treated controls. At the time of presumed irradiation, (i.e. 24 h after administration of the drug to the non-irradiated mice), there was no significant difference between the control mice and mice treated with IRS-19 in numbers of femoral and spleen GM-CFC. In contrast, the number of nucleated femoral cells decreased significantly in the group treated with IRS-19. Moreover, treatment with IRS-19 caused a sustained increase in serum colony-stimulating activity which was followed by an enhanced repopulation of GM-CFC in the femoral marrow and spleen. Administration of the agent 24 h prior to irradiation rather than postirradiation appeared most effective with respect to radioprotection. Intravenous rather than i.p. and p.o. was the most effective route of administration in the mouse. Furthermore, single, high-dose injection appeared to be more effective than repeated, lower dose injections. Results suggest that the radioprotective properties associated with the administration of IRS-19 are largely a consequence of the induction of haemopoietic colony-stimulating activities and potentially the activation and/or enhancement of cytokine cascades in the recipient animals. These changes may ultimately impact the cell cycle profile of the haemopoietic cells and therefore their ability to withstand and/or recover from radiation insult.

Adjuvants, Immunologic↗

PubMed1982

Bone-marrow imaging with indium-111 chloride in aplastic anemia and myelofibrosis: concise communication.

Twenty-nine patients with aplastic anemia and 11 patients with myelofibrosis were evaluated with indium-111 chloride bone-marrow imaging, ferrokinetics, and bone-marrow core biopsies. There was good correlation between the erythrocyte cellularity of the marrow and the In-111 bone-marrow scan grades in most patients. In some, the overall scan grade tended to underestimate the erythroid elements because the core biopsy had been taken from the area of the greatest radionuclide concentration on the scan. In patients with aplastic anemia, there was good correlation between the plasma iron clearance t1/2 and the scan grade. Less agreement was found in the comparison between the Fe-59 sacral and organ counts and the red-cell iron utilization. In patients with myelofibrosis, there was poor correlation between the surface counts over the sacrum and the red-cell iron utilization. Plasma iron clearances were abnormally short and were unrelated to the transferrin saturation levels. Eighteen patients were studied several times to evaluate their responses to steroid therapy. In all, there was good correlation between the bone-marrow imaging, the erythrocyte cellularity, ferrokinetics, and the patient's response to therapy. Indium-111 bone-marrow imaging is useful both in evaluating marrow erythroid activity and in following the response to therapy in patients with these diseases.

Adolescent↗

PubMed1991

Chronic myelomonocytic leukemia transformation in polycythemia vera.

Myelodysplasia is an increasingly recognized complication of polycythemia vera (PCV) which often precedes leukemic transformation. This paper describes two patients with aggressive chronic myelomonocytic leukemia, previously undescribed as a complication of PCV. Both patients presented with rapidly increasing splenomegaly which was resistant to treatment with hydroxyurea and external beam irradiation. Splenectomy precipitated fatal hepatic failure in one patient. The other died shortly after transformation to acute myelomonocytic leukemia (FAB M4 classification). Pathology of the bone marrow, spleen, and liver was remarkable for extensive infiltration by dysplastic myeloid elements. Survival was short, only 4-6 months from diagnosis. The unique characteristics in these patients were: (i) prior history of PCV; (ii) rapidly increasing splenomegaly resistant to standard therapy; (iii) absence of overt marrow fibrosis; (iv) hypercellularity (greater than or equal to 90% cellular) of the bone marrow with dysplasia in the myeloid, erythroid, and megakaryocytic cell lines; (v) peripheral monocytosis greater than 1 x 10(9); and (vi) extensive infiltration of the spleen and liver by dysplastic myeloid cells. In addition, the patient who subsequently developed acute leukemia had been treated with hydroxyurea under the PVSG-08 protocol, providing further evidence of the potential leukemogenic effects of this agent.

Aged↗

PubMed1984

Ectopic bone marrow development in experimental busulfan-induced hypoplastic anemia in mice.

The intramuscular implantation of devitalized bone matrix in 42 mice with busulfan-induced bone marrow failure and in 42 control mice led to the sequential formation of ectopic cartilage, bone and bone marrow. The morphological volumetric estimation of these components in the hypoplastic mice showed a significant increase in cartilage and a decrease in hematopoietic bone marrow as compared with control mice. The cellularity in the ectopic hematopoietic bone marrow was similar to that of sternal bone marrow. The possible significance of these findings is discussed.

Anemia, Aplastic↗

PubMed2001

Role of stromal cells in osteoclast differentiation in bone marrow.

Bone marrow stromal cells have been considered to play an important role in osteoclast differentiation. However, the interaction of these cells in vivo has not been clearly demonstrated. To clarify this, we examined the distribution of alkaline phosphatase (ALPase) and tartrate-resistant acid phosphatase (TRAPase) activities as markers of osteoblastic and osteoclastic cells, respectively. Rat tibiae were fixed and embedded in Technovit 8100 or paraffin. ALPase and TRAPase activities were detected simultaneously on a plastic section by the azo-dye method. ALPase activity was detected on the plasma membranes of osteoblasts and some bone marrow fibroblastic stromal cells. These ALPase-positive cells were connected to each other by cytoplasmic processes, forming a cellular network in bone marrow. The ALPase activity of fibroblastic stromal cells tended to be stronger in those cells close to the bone surface than in the cells in the center of bone marrow. Reticular fibers in bone marrow were found to form a network. The ALPase-positive fibroblastic stromal cells may be reticular cells, because the localization of those cells was in accord with the localization of reticular fibers. The TRAPase-positive mononuclear cells and osteoclasts were mostly observed to be associated with the intensely ALPase-positive fibroblastic stromal cells. Immunoreactivity of osteoclast differentiation factor (ODF) was found in the fibroblastic stromal cells. These findings suggest that the network of ALPase-positive fibroblastic stromal cells in bone marrow serves as a guide for the migration of osteoclast precursor cells toward the bone surface, and may control the differentiation and activity of osteoclasts.

Acid Phosphatase↗

PubMedDate not supplied

[Pathohistological characteristics of myelodysplastic syndromes: diagnostic and prognostic significance].

INTRODUCTION: Pathohistological (PH) analysis is recommended as basic diagnostic procedure during the investigation of myelodysplastic syndromes (MDS). AIM: The aim of this paper was to investigate diagnostic and prognostic significance of bone marrow PH features in patients with MDS, and its relation to cytological characteristics of bone marrow aspirate. METHODS: Cellularity, disorder of marrow histotopography, quantity of hematopoiesis lineages, cellular atypia, the amount of myeloblasts, and stromal changes were particularly analyzed in trephines of 236 patients with primary MDS. RESULTS: In most cases (78.4%) hypercellular bone marrow was observed, although in 10.2% patients hypocellular subtype of MDS was diagnosed. Erythropoiesis dislocation was present in 64.7% patients, dislocation of MK-poiesis in 50.9% patients, while 61.3% had dislocation of granulopoesis (so-called ALIP phenomenon). In most cases three lineage hyperplasia was present, while relative hypoplasia of E- and MK-lineage was found in 1/4 cases, each, particularly in advanced MDS. Morphological features of dyseritropoiesis and dysmegakaryocytopoiesis were present in 42.5% and 75.7% cases, respectively. Different stages of reticulin and collagen fibrosis were observed in 55.5% patients, while 7.6% had hyperfibrotic subtype of MDS. Comparative analysis of cytological and histological features of MDS bone marrow showed positive correlation between two methods only in respect of estimation of eritropoiesis quantity, presence of dismegakaryocytopoiesis and "reactive" cells. The univariate analysis showed that MK- and G-lineage dislocation, quantity of E- and G-lineage, and presence of dysmegakaryocytopoiesis, were prognostic indicators for short survival and evolution of the disease in MDS patients. However, multivariate analysis showed that only G-lineage dislocation was independent prognostic variable for survival in MDS cases. CONCLUSION: PH analysis is irreplaceable diagnostic procedure during MDS investigation, since it provides reliable information of cellularity, architectural disorganization, number of megakaryocytes and alterations of marrow stroma. In addition, PH analysis provides numerous important prognostic information.

Bone Marrow↗

PubMed2004

Differential inhibition of invasion and proliferation by bisphosphonates: anti-metastatic potential of Zoledronic acid in prostate cancer.

OBJECTIVES: To determine the mode of action of Zoledronic acid in the inhibition of metastasis in prostate cancer and the reduction of prostate cancer bone metastases. METHODS: Benign and malignant primary prostatic epithelial cells (PEC) and the PC-3 prostate cancer cell line were studied in co-culture using human bone marrow stroma in the presence of escalating doses of EDTA, Clodronate, Pamidronate and Zoledronic acid. PEC binding and colony growth in bone marrow stroma was measured using standardised quantitative techniques. PEC cellular invasion through Matrigel and an endothelial monolayer was measured either in invasion chambers or by the measurement of endothelial monolayer permeability to fluorescent dextran. Co-culture supernatants were assayed for specific cytokine levels. Bone marrow cellular toxicity was assessed using a standard Mix assay. RESULTS: Treatment of PEC with up to 100 microM bisphosphonate did not affect their ability to bind to bone marrow endothelium or stroma. Bone marrow endothelial permeability was reduced by 100 microM Zoledronic acid by 3.8% (p = 0.03856). Both Pamidronate (40% at 100 microM, p < or = 0.05) and Zoledronic acid inhibited PEC invasion, with Zoledronic acid being the most potent (40% at 10 microM, p < or = 0.05 rising to 91% at 100 microM, p < or = 0.001). Zoledronic acid inhibits malignant PEC proliferation in bone marrow stroma co-culture (26.5% at 10 microM rising to 66.5% at 40 microM). This was accompanied by changes within the cytokine milieu with a >800% rise in TIMP-2. CONCLUSION: Zoledronic acid is a potent inhibitor of PEC invasion across bone marrow endothelium and colony formation with the bone marrow stroma, affecting the MMP: TIMP-2 balance to favour MMP inhibition.

Antineoplastic Agents↗

PubMed1994

Hematopoietic colony stimulatory factor formation by murine mesangial cells: gene expression and biological activity.

This study examined the ability of mesangial cells to synthesize colony-stimulating factors (CSF), cytoregulatory peptides associated with the differentiation and proliferation of hematopoietic cells. Conditioned media obtained from SV-40 transformed murine mesangial cells stimulated the growth of murine bone marrow progenitor cells of the myeloid series. Differential analysis of these cells showed the presence of both macrophages and granulocytes. Cellular identification of bone marrow colonies stimulated in response to mesangial cell conditioned media was examined by flow cytometric analysis and revealed the presence of F4/80 antigen positive macrophages (67%) and Gran-1 antigen positive granulocytes (21%). Neutralizing antibodies to macrophage colony-stimulating factor (M-CSF) and granulocyte-macrophage colony-stimulating factor (GM-CSF) but not antibody to interleukin-3 (IL-3), or stem cell factor (SCF) significantly inhibited the growth of the progenitor cells induced by mesangial cell conditioned media. Utilizing Northern blot analysis, murine mesangial cells expressed mRNA transcripts for M-CSF, GM-CSF, and granulocyte colony-stimulating factor (G-CSF). Further studies were performed to determine optimal incubation conditions for mesangial cell CSF gene expression. These studies revealed that both GM-CSF and G-CSF mRNA were maximally expressed at early time points (4 and 8 h of incubation), while M-CSF mRNA expression remained unchanged during the incubation of mesangial cells from 4-48 h. Incubation of mesangial cells with various concentrations of fetal bovine serum (FBS, 0.5-15%) markedly increased the mRNA expression of M-CSF, GM-CSF and G-CSF in a dose-dependent manner. These studies indicated that transformed murine mesangial cells are able to synthesize and secrete biologically active CSF that are associated with the migration and proliferation of circulating mononuclear cells in the glomerulus. Furthermore, observations regarding the role of duration of incubation and the media concentration of FBS on mesangial cell CSF mRNA expression may provide useful data to understand the optimal conditions for studies that examine the gene expression of basal or inducible CSF in mesangial cells.

Animals↗

PubMed2007

Manipulation of proliferation and differentiation of human bone marrow-derived neural stem cells in vitro and in vivo.

Recent evidence has demonstrated that neural stem cells (NSC) can be expanded from a variety of sources, including embryos, fetuses, and adult bone marrow and brain tissue. We have previously reported the generation of adult rat bone marrow-derived cellular spheres that are morphologically and phenotypically similar to neurospheres derived from brain NSC. Here we show that adult human bone marrow-derived neural stem cells (HBM-NSC) are capable of generating spheres that are similar to brain neural-derived neurospheres. Additionally, we sought to promote proliferation and differentiation of HBM-NSC through transduction with nonreplicative recombinant adenovirus encoding the cDNA sequence for Gli, rADV-Gli-1; sonic hedgehog, rADV-Shh; or Nurr1, rADV-Nurr1. Immunocytochemistry and RT-PCR analysis showed that HBM-NSC could be efficiently expanded and differentiated in vitro and that HBM-NSC transduced with rADV-Gli-1 or rADV-Shh dramatically increased NSC time-related proliferation; however, Nurr1 had no effect on proliferation. We also transplanted HBM-NSC into chicken embryos to examine their potential function in vivo. We found that transduction of HBM-NSC with rADV-Gli-1 or rADV-Shh and subsequent transplantation into chicken embryos increased HBM-NSC proliferation, whereas rADV-Nurr1 promoted migration and differentiation in vivo. Our findings suggest that HBM-NSC can be efficiently expanded and differentiated in vitro and in vivo by overexpressing Gli-1, Shh or Nurr1.

Animals↗

PubMed2001

Modeling pO(2) distributions in the bone marrow hematopoietic compartment. II. Modified Kroghian models.

Hematopoietic cells of various lineages are organized in distinct cellular architectures in the bone marrow hematopoietic compartment (BMHC). The homogeneous Kroghian model, which deals only with a single cell type, may not be sufficient to accurately describe oxygen transfer in the BMHC. Thus, for cellular architectures of physiological significance, more complex biophysical-transport models were considered and compared against simulations using the homogeneous Kroghian model. The effects of the heterogeneity of model parameters on the oxygen tension (pO(2)) distribution were examined using the multilayer Kroghian model. We have also developed two-dimensional Kroghian models to simulate several cellular architectures in which a cell cluster (erythroid cluster) or an individual cell (megakaryocyte or adipocyte) is located in the BMHC predominantly occupied by mature granulocytes. pO(2) distributions in colony-type cellular arrangements (erythroblastic islets, granulopoietic loci, and lymphocytic nodules) in the BMHC were also evaluated by modifying the multilayer Kroghian model. The simulated results indicate that most hematopoietic progenitors experience low pO(2) values, which agrees with the finding that low pO(2) promotes the expansion of various hematopoietic progenitors. These results suggest that the most primitive stem cells, which are located even further away from BM sinuses, are likely located in a very low pO(2) environment.

Erythrocytes↗

PubMed1990

[Classification of erythroblastic islets of the bone marrow and the study of their cellular composition].

Cell composition of erythroblastic islands (EI), normal and at the phase of stimulation and inhibition of erythropoiesis at modelling of heat adaptation has been studied on hemopoietic tissue of 108 rats. In the hemopoietic tissue, together with EI of the 1st, 2nd and 3d classes of maturity, that have in their composition correspondingly up to 8, from 9 up to 16 and above 16 nuclei-containing erythroid cells, there are involutive and reconstructing EI. The involutive EI are presented as nuclei-containing erythroid cells, that are not able to divide and are at late stages of differentiation: polychromatophilic and oxyphilic normoblasts, as well as reticulocytes. The reconstructing EI have in their composition both erythroid cells, that are not able to divide, and erythroid cells (pro-, erythroblasts and basophilic normoblasts), that are at early stages of differentiation. Application of the EI classification suggested, takes into account the rate, with which the erythroid cell-predecessors are drawn into erythropoiesis and intensity of erythroid differentiation. Therefore, it is possible to obtain earlier and more exact data on the state of hemopoiesis in comparison with traditional hematological methods.

Animals↗

PubMed1989

Haemopoiesis in murine bone marrow and spleen after fractionated irradiation and repeated bone marrow transplantation. I. Erythropoiesis.

Erythropoiesis was studied in mice repeatedly subjected to individual doses of 3 Gy of 60Co gamma-rays at 4-day intervals up to a total dose of 24 Gy on the basis of total bone marrow and spleen cellularity follow-up and analysis of myelograms and splenograms. Half of the mice received 10(6) nuclear cells of syngeneic bone marrow after each fractional radiation dose. It was mainly the spleen which was involved in the adaptation and regeneration of erythropoiesis, its contribution to total erythropoiesis in bone marrow recipients having been as much as 73.9% (day 20 of experiment, total dose 15 Gy). In mice only irradiated, the number of nuclear cells of erythroid lineage decreased to zero values sooner in the spleen (day 16 of experiment, total dose 12 Gy) when compared to the bone marrow (day 24 of experiment, total dose 18 Gy). Analysis of the results of collections made on day 9 after the last irradiation, however, revealed that the haemopoietic microenvironment of the spleen and haemopoietic cells capable of differentiation in the erythroid direction are so resistant to irradiation in only irradiated mice that erythropoiesis in their spleens exhibits signs of regeneration even after the highest total dose of 24 Gy.

Animals↗

PubMedDate not supplied

[Action of thymosin on the ultrastructure of the bone marrow in the rat].

A preparation isolated from thymus extract and possessing thymosin-like activity was studied for its influence on the ultrastructure of the rat bone marrow cells. A dose of the preparation adequate to therapeutic one (7 mg/kg) causes a transitory "irritation" (dystrophy and stimulation) in cellular elements of bone marrow. A supertherapeutic dose (70 mg/kg) has a definitely toxic effect on its cells and is characterized by an expressed tropism to the endothelium of sinusoids and capillaries.

Animals↗

PubMed2006

Preparing the "soil": the premetastatic niche.

Current focus on cancer metastasis has centered on the intrinsic factors regulating the cell autonomous homing of the tumor cells to the metastatic site. Specific up-regulation of fibronectin and clustering of bone marrow-derived cellular infiltrates coexpressing matrix metalloproteinases in distant tissue sites before tumor cell arrival are proving to be indispensable for the initial stages of metastasis. These bone marrow-derived hematopoietic progenitors that express vascular endothelial growth factor receptor 1 mobilize in response to the unique array of growth factors produced by the primary tumor. Their arrival in distant sites represents early changes in the local microenvironment, termed the "premetastatic niche," which dictate the pattern of metastatic spread. Focus on the early cellular and molecular events in cancer dissemination and selectivity will likely lead to new approaches to detect and prevent metastasis at its earliest inception.

Bone Marrow Cells↗

PubMed1983

Characteristics of the adenylyl cyclase system of differentiating rabbit bone marrow erythroblasts.

Changes in the cellular content of cyclic AMP and in the activities of adenylyl cyclase, cyclic AMP phosphodiesterase and cyclic AMP-dependent protein kinases during differentiation of rabbit bone marrow erythroid cells were investigated. The cells were separated by velocity sedimentation at unit gravity into six fractions corresponding to different stages of development: proerythroblasts, basophilic erythroblasts, polychromatic cells, early orthochromatic and late orthochromatic cells and reticulocytes. Adenylyl cyclase activity was found to decrease continuously as the cells developed, from approx. 180 pmoles cyclic AMP formed/mg of protein/20 min in proerythroblasts to 10 pmoles in circulating reticulocytes. The proerythroblasts were the richest cells in cyclic AMP which is present at a cellular concentration of approx. 1.4 microM. In basophilic cells the cyclic AMP content was about 80% lower than in proerythroblasts. No further changes in cyclic AMP levels were observed after the final cell division. Cyclic AMP phosphodiesterase was found to be very active in the most immature cells, the proerythroblasts. After differentiation into basophilic erythroblasts, a 4-fold decrease in cyclic AMP phosphodiesterase activity occurred. In polychromatic cells there was a further drop in phosphodiesterase activity and after the last cell division the enzyme activity was constant and very low. Both cytosolic cyclic AMP-binding capacity and cytosolic cyclic AMP-dependent protein kinase activity decreased in dividing rabbit bone marrow erythroblasts when calculated in terms of cell number but remained constant per cell volume. After the final cell division, cyclic AMP-dependent protein kinase activity did not change further, whereas cyclic AMP-binding capacity declined. There were no qualitative but only quantitative changes in the cyclic AMP-binding proteins that are present in the cytosol of developing erythroblasts. In the immature cells, the apparent Kd for the interaction of binding proteins with cyclic AMP was 4 . 10(-8) M. The data suggest that changes in cyclic AMP-binding activity during differentiation of erythroid cells are due both to changes in the amount of binding proteins and their affinity for cyclic AMP. The phosphorylation of rabbit erythroblast plasma membrane proteins by membrane-associated protein kinase(s) was found to be cyclic AMP-dependent in dividing cells during the early stages of differentiation. When the erythroid cells reach the non-dividing stage in their development, autophosphorylation of membrane ghosts was no longer stimulated by cyclic AMP.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenylyl Cyclases↗