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Results for “Granulocyte Precursor Cells”

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PubMed1993

Further study of internal autocrine regulation of multipotent hematopoietic cells.

We have extended the study of the effects of antisense oligodeoxynucleotides on hematopoietic colony formation to include the effects of antisense to granulocyte-macrophage colony-stimulating factor (GM-CSF), granulocyte colony-stimulating factor (G-CSF), and macrophage colony-stimulating factor (M-CSF) on bone marrow cultures. GM-CSF antisense and GM-CSF receptor antisense cause an increase in mixed erythroid:nonerythroid colonies and a decrease in mixed nonerythroid colonies, which is an effect opposite to that described previously for erythropoietin (Epo) and Epo receptor antisense. The effect of GM-CSF antisense oligomer is not abrogated by the presence of the ligand in the culture. Antisense oligomers to G-CSF and M-CSF have no effect. When Epo and GM-CSF antisense oligomers are added simultaneously, the effects seem to be independent, with the GM-CSF antisense predominating. These data support the hypothesis of internal autocrine regulation of multipotent hematopoietic precursor cells, and extend the concept to myeloid as well as erythroid differentiation.

Animals↗

PubMed1990

Actions of human interleukin-4/B-cell stimulatory factor-1 on proliferation and differentiation of enriched hematopoietic progenitor cells in culture.

We studied the effects of recombinant human interleukin-4 (IL-4) on colony formation by enriched hematopoietic progenitors. IL-4 alone did not support colony formation at all. When IL-4 was combined with granulocyte colony-stimulating factor (G-CSF), the number of pure neutrophil colonies increased three times over that supported by G-CSF alone. IL-4 added 5 days after the addition of G-CSF failed to exert this synergistic effect, indicating that IL-4 acts on the early stage of proliferation. The mapping experiments (sequential observation of colony formation) have clearly shown that IL-4 did not initiate progenitor cell proliferation. Based on these data, IL-4 may possess a direct action on progenitor cells; however, it can only act as a costimulant with G-CSF. In contrast, IL-4 had possible inhibitory effects on macrophage colony formation supported by interleukin-3 (IL-3) and macrophage colony-stimulating factor (M-CSF). In other words, IL-4 may induce progenitor cells to become sensitive to G-CSF and thereby induce neutrophil differentiation. Delayed addition experiments demonstrated that human IL-4, unlike murine IL-4, could support neither proliferation nor survival of erythroid burst or mixed colony forming cells. Neutrophil colony forming cells only survived and recovered after addition of G-CSF and erythropoietin on day 5 of incubation. On the other hand, IL-3 supported neutrophil, erythroid burst, and mixed colony forming cells as reported previously (Sonoda et al, Proc Natl Acad Sci USA, 85:4360, 1988). These results led us to propose that IL-4 possibly acts with more mature progenitor cells than those of IL-3 or granulocyte-macrophage (GM)-CSF.

Bone Marrow↗

PubMed1991

Action of benzene metabolites on murine hematopoietic colony-forming cells in vitro.

Five benzene metabolites--phenol, catechol, hydroquinone, parabenzoquinone, and trans,trans-muconaldehyde--were tested in vitro in murine hematopoietic cell cultures for erythrocytic (BFU-E and CFU-E) and granulocytic (CFU-C) colony growth. The dose range was 4 x 10(-4) to 4 x 10(-8) M. Of these compounds, phenol showed the lowest toxicity. In general, CFU-E cultures were far more sensitive than CFU-C and BFU-E. The results are discussed in relation to the test system used, the in vivo sensitivity of CFU-E, and the lack of knowledge about in vivo concentrations of these compounds.

Animals↗

PubMed1990

Granulocyte colony-stimulating factor.

Granulocyte colony-stimulating factor was discovered during attempts to define the normal regulators present in cell supernatants that could induce terminal differentiation of the murine myeloid leukemic cell line WEHI-3B D+. The purification and subsequent cloning of both murine and human G-CSF allowed the normal functions of this molecule to be elucidated and indicated that it was a relatively lineage-specific stimulator of the survival, proliferation, and differentiation of precursor cells of the neutrophilic granulocyte cell lineage as well as an activator of mature neutrophil function. Murine and human G-CSFs as well as the ligand-binding domains of G-CSF receptors have been strongly conserved so that the biological activities and receptor-binding characteristics of G-CSFs are completely species cross-reactive. The evolutionary conservation of G-CSFs is suggestive of an important role for the molecule in maintaining neutrophil levels and activity in vivo, a role amply supported by a series of animal experiments and clinical trials that have been performed recently. These experiments and trials have suggested that G-CSF will be clinically useful in augmenting patients' resistance to certain infections, in enhancing the neutrophil responses of some patients with reduced granulocyte counts or defective granulocytes, and in reducing the decline in granulocytes that occurs during chemotherapy or irradiation therapy and bone marrow transplantation. The special capacity of G-CSF among the CSFs to induce terminal differentiation in some myeloid leukemias is not understood in molecular terms. However, the capacity of G-CSF to stimulate proliferation in some myeloid leukemias as well argues that caution needs to be exercised in the timing of G-CSF administration and patient selection before considering this form of therapeutic approach.

Amino Acid Sequence↗

PubMed1990

Effects of recombinant human interleukin-3 on human hematopoietic progenitor and precursor cells in vivo.

DNA-synthesis rates and concentrations of bone marrow (BM) and peripheral blood (PB) progenitor cells were studied in 22 patients treated with recombinant human interleukin-3 (rhIL3) as part of a clinical phase I/II study. Recombinant hIL3 at doses of 60 to 500 micrograms/m2 was administered by subcutaneous bolus injection for 15 days to 13 patients with solid tumors and preserved hematopoietic function and to nine patients with bone marrow failure, including five with myelodysplastic syndromes. Following treatment with rhIL3, the percentage of actively cycling BM erythroid (BFU-E) and multilineage (CFU-GEMM) progenitors in patients with preserved hematopoietic function increased from 16% to 36% (P less than .05) and from 10% to 40% (P less than .01), respectively. The DNA-synthesis rates of early and late granulocyte macrophage progenitor cells increased from 11% to 26% (CFU-GM day 14; P less than .02) and from 13% to 30% (CFU-GM day 7; P less than .05). There was an increase in BM cellularity from 37% to 58%, and of the myeloid to erythroid ratio from 1.4 to 3.2, while the concentration of marrow progenitors on a per cell basis was unchanged or slightly decreased. The frequencies of blast cells in the BM were unchanged. Mean levels of PB CFU-GM day 14 and CFU-GEMM were 100% and 72% above baseline values after 7 days of rhIL3 but only 25% and 28% above initial levels at the end of treatment. Peripheral blood BFU-E were reduced in the majority of patients with normal marrow after both 7 and 15 days of rhIL3. No augmentation of circulating BFU-E and CFU-GEMM was seen in 5 patients with MDS who had few or no PB BFU-E or CFU-GEMM initially. Total leukocyte, neutrophil, and eosinophil counts increased significantly (P less than .01) in 21 of 22 patients with a peak response after a median of 13 days of rhIL3. While a small increase in reticulocytes was not accompanied by an elevation of the hemoglobin or hematocrit, platelet counts increased by 50% in patients with preserved marrow function. Thus, rhIL3 induces a multilineage response in vivo, apparently by stimulating proliferation of multipotential and lineage-restricted progenitors. It remains to be determined whether this is due to direct or indirect effects on the progenitor cells.

Adult↗

PubMed1995

Synergism of interleukin-12 and interleukin-3 on development of hematopoietic progenitors.

The recently cloned cytotoxic lymphocyte maturation factor [CLMF] also called NK cell stimulatory factor [NKSF] or interleukin-12 [IL-12] has been described as a growth factor for mature lymphoid cells. The present study investigated whether purified recombinant human IL-12 could stimulate CFU colony growth. Source of progenitor cells were peripheral blood cells depleted of adherent, CD2- and CD56-positive cells. RhIL-12 was investigated either alone or in combination with rhIL-3, rhIL-6 and rhGM-CSF. RhIL-12 alone did not support colony formation of myeloid or erythroid progenitors. RhIL-12 in combination with rhIL-3 increased the numbers of BFU-E and CFU-GM. No synergism or additive effect was seen with the combination of rhIL-12 and rhGM-CSF or rhIL-12 and rhIL-6. An additive increase in the number of granulocytic colonies was observed when rhIL-3, rhIL-6 and rhGM-CSF were used together with rhIL-12. Our results therefore suggest that, in addition to being a potent lymphopoietic stimulator, IL-12 acts synergistically with IL-3 in enhancing the sensitivity of hemopoietic progenitors to IL-3.

Dose-Response Relationship, Drug↗

PubMed1978

Effect of surgery on granulocyte/macrophage colony-stimulating factor.

Eighteen surgical patients were studied to determine the effect of anesthesia (general or spinal) and surgery on serum and urinary colony-stimulating factor(s) (CSF). CSF is a leukopoietin that stimulates proliferation of macrophages and granulocytes from bone marrow precursor cells. CSF was assayed by adding aliquots of serum or urine to semisolid agar cultures of bone marrow cells and scoring the number of colonies developing after 7 days of incubation. In all but 1 case, a 3- to 30-fold increase in the 24 hour excretion of urinary CSF was seen on the day of surgery and the first postoperative day. CSF urinary excretion began declining toward normal by the second postoperative day. A parallel increase in granulocyte count, a delayed rise in monocytes, and a decline in absolute lymphocyte counts were also observed. The data suggest that immediately postoperatively there may be a strong stimulus to granulocyte/macrophage proliferation. More rapidly proliferating cells would be anticipated to have increased vulnerability to toxicity from cell cycle-active chemotherapeutic agents.

Adult↗

PubMed2005

Bone marrow features in children with HIV infection and peripheral blood cytopenias.

HIV infection is associated with numerous abnormalities affecting both the myeloid and lymphoid lineages. We studied the features associated with peripheral cytopenias as the first sign of HIV infection in children. Peripheral blood (PB) counts, PB and bone marrow (BM) lymphocyte subsets, as well as viral load and serum levels of ferritin, vitamin B12, and folic acid were determined. Five children were naive of treatment (Group 1) and three were under HAART (Group 2). In Group 1 all patients had anemia of chronic disease. One had a bone marrow culture positive for Mycobacterium avium intracellulare and pancytopenia. Besides this, neutropenia and thrombocytopenia were seen in one patient each. In Group 2 anemia was found in all, neutropenia in one, and thrombocytopenia in two patients. Peripheral blood cytopenias were due to HAART toxicity in one patient. In the other two they were due to iron or folate deficiency. Bone marrow cytology showed cell abnormalities mainly in granulocytic precursors and megakaryocytes. All except two (taking HAART) patients had a high viral load. There was a straight correlation between viral load in PB and bone marrow. Viral load was correlated with peripheral CD4 but not with CD8 lymphocytes. A decrease in bone marrow B lymphocytes was seen in all patients. The introduction of HAART improved peripheral cytopenias. Bone marrow examination was useful for determining the etiology of the cytopenias and for detection of opportunistic infection. Hemopoietic cell abnormalities were similar to those seen in adults and indicative of HIV infection.

Anemia, Aplastic↗

PubMed1979

Stimulation of human haemopoietic cells by colony stimulating factors: sensitivity of leukaemia cells.

The sensitivity of populations of human granulocyte precursors to factors with colony stimulating activity (CSA) was assessed in agar culture in vitro. The mean threshold of stimulation was estimated by analysis of dose-response curves of clone growth against concentration of CSA. This method of assessment has the advantage that CSA production by cells contaminating the population under test does not affect results. Marrow cells from patients with acute myeloid leukaemia were less sensitive to CSA than marrow cells from normal individuals. Sensitivities of cells from chronic granulocytic leukaemia and from chronic myelomonocytic leukaemia were within the normal range, but this group also tended to require more CSA than controls. In addition, sensitivities of granulocyte precursors from patients with acute myeloid leukemia were closely related to the culture pattern, and thus to the remission probability. The significance of this relationship is discussed.

Adolescent↗

PubMedDate not supplied

[Proliferative and differentiation properties of bone marrow hematopoietic stem cells in CBA mice of various ages].

Hemopoietic bone marrow stem cells (CFCs) of young (3-5 months) and old (23-24 months) were studied according to their ability to form colonies in spleens of the lethally irradiated animals. The number, morphology and volume of CFCs were microscopically examined. The content of CFCs remained unchanged during aging. The number of erythroid colonies decreased in old mice, while that of granulocyte-macrophage and mixed colonies did not change. The megakaryocyte colonies showed even an increase with age. Volumes of all the colony types, except megakaryocyte, reduced. The results obtained thus reflect some age-related features of early stages of the stem-cell differentiation.

Aging↗

PubMed1991

Hemin stimulation of hemopoiesis in murine long-term bone marrow culture.

The effect of various concentrations of exogenous hemin on cellularity and hemopoietic clonal potential of cells maintained in murine long-term marrow cultures (LTBMC) was studied. Hemin, at concentrations of 1 and 10 microM, was added weekly to LTBMC and was found to produce a significant increase in cellularity for up to 8 weeks in culture. Lower concentrations of hemin (0.1 microM) were more effective for sustained cellularity in older cultures (10-12 weeks). Prior exposure of the adherent cell layer to high concentrations of hemin (10 microM) was found to have a beneficial effect on the support of newly seeded cultures; however, the effect of lower hemin concentrations (0.1-1 microM) on stromal cell layer formation was not significant. Supplementation of hemin for the first week in culture increased cumulative cell production as well as the number of granulocyte-macrophage colony-forming units (CFU-GM), and longevity of hemopoiesis in LTBMC was significantly increased with 0.1 microM hemin. In contrast with data obtained in short-term cultures, hemin in this system primarily affected the myeloid line of differentiation, whereas there was a less noticeable effect on the early erythroid progenitors (erythroid burst-forming units, BFU-E). Hemin, at 0.1 microM, increased spleen colony-forming units (CFU-S) to numbers several-fold higher than those of the control. Results suggest that hemin may produce mobilization of hemopoietic cells and committed precursors from adherent cells into suspension. Further, supplementation with hemin in LTBMC significantly increased the myeloid progenitor compartment and longevity of culture without altering the erythroid compartment.

Animals↗

PubMed2005

Correlation between differentiation plasticity and mRNA expression profiling of CD34+-derived CD14- and CD14+ human normal myeloid precursors.

In spite of their apparently restricted differentiation potentiality, hematopoietic precursors are plastic cells able to trans-differentiate from a maturation lineage to another. To better characterize this differentiation plasticity, we purified CD14- and CD14+ myeloid precursors generated by 'in vitro' culture of human CD34+ hematopoietic progenitors. Morphological analysis of the investigated cell populations indicated that, as expected, they consisted of granulocyte and monocyte precursors, respectively. Treatment with differentiation inducers revealed that CD14- cells were bipotent granulo-monocyte precursors, while CD14+ cells appeared univocally committed to a terminal macrophage maturation. Flow cytometry analysis demonstrated that the conversion of granulocyte precursors to the mono-macrophage maturation lineage occurs through a differentiation transition in which the granulocyte-related myeloperoxidase enzyme and the monocyte-specific CD14 antigen are co-expressed. Expression profiling evidenced that the observed trans-differentiation process was accompanied by a remarkable upregulation of the monocyte-related MafB transcription factor.

Antigens, CD34↗

PubMed1994

Peripheral blood mononuclear cells from patients with rheumatoid arthritis suppress erythropoiesis in vitro via the production of tumor necrosis factor alpha.

Anemia is a frequent manifestation of rheumatoid arthritis, with a probably multifactorial etiology. We investigated the effect of peripheral blood mononuclear cell supernatants (PBMCS) from rheumatoid arthritis (RA) patients on hematopoietic colony formation in vitro, by using a methylcellulose assay. PBMCS from patients suppress in vitro erythroid (BFU-E), mixed-lineage (CFU-GEMM) and to a lesser degree granulocyte-macrophage (CFU-GM) progenitors. PBMCS from anemic RA patients were more suppressive for BFU-E than those from non-anemic patients. Addition of antibodies to tumor-necrosis factor alpha (TNF alpha) almost completely reversed the inhibition of BFU-E and CFU-GEMM, but had little effect on the CFU-GM colony formation. Antibodies to interferon-gamma (IFN gamma) and interleukin-1 (IL-1) were not effective. The above data suggest that PBMCS from RA patients suppress in vitro erythropoiesis via the production of TNF alpha; a pathogenetic role for TNF alpha in the anemia of RA can be implied.

Adult↗

PubMed1994

Interleukin-10 promotes the growth of megakaryocyte, mast cell, and multilineage colonies: analysis with committed progenitors and Thy1loSca1+ stem cells.

The growth-promoting activities of interleukin-10 (IL-10) were assessed in hematopoietic colony-forming assays. We found that IL-10 failed to support the clonal growth of normal and lineage-depleted (Lin-) bone marrow (BM) cells. Furthermore, IL-10 neither enhanced nor suppressed colony formation by eosinophil, neutrophil, or macrophage progenitors when combined with a variety of factors. IL-10 stimulated a modest increase in erythropoietin (Epo)-dependent erythroid colonies but had no effect on the burst-promoting activities of IL-3. However, the combination of IL-10 plus IL-3 resulted in the enhanced growth of mast cell progenitors. In addition to its mast cell stimulating activity, IL-10 promoted the growth of megakaryocyte (Mk) and Mk-mixed colonies when combined with Epo or with Epo plus IL-3, IL-6, or IL-11. Comparative studies showed that the megakaryocyte potentiating activity of IL-10 is roughly equivalent to that of IL-6 and IL-11. In experiments using Thy1loSca1+ stem cells, IL-10 was shown to enhance the number of cells initiating IL-3-dependent colony formation. IL-10 also costimulated increased colony formation when used with IL-3 and another factor such as IL-1, IL-6, and granulocyte colony-stimulating factor (G-CSF). Cellular analysis of the resulting colonies indicated that IL-10 increases the formation of multilineage colonies containing erythrocytes, megakaryocytes, and/or mast cells. The ability of IL-10 to cooperatively regulate various stages of hematopoietic development is discussed.

Animals↗

PubMed1983

In vitro migration of avian hemopoietic cells to the thymus: preliminary characterization of a chemotactic mechanism.

Hemopoietic cells differentiating in the thymus have an extrinsic origin; it has been suggested that, in avian embryos, the thymic epithelium can recruit precursor cells at several precisely determined periods by a chemotactic mechanism. We have used a chemotactic chamber (Zigmond, S.H.: J. Cell Biol. 75, 606-616 (1977] to analyse quantitatively the behaviour of hemopoietic precursor cells confronted with thymuses. The embryonic bone marrow was found to be a rich source of precursor cells carrying thymic lymphocyte potentialities. In the Zigmond chamber, precursor cells exhibited a strong chemotactic response to a concentration gradient of substances secreted by attractive thymuses from 7 1/2-day-old chick embryos; the mesonephros from embryo of the same age had no effect. In addition 7 1/2-day-old attractive and 10-day-old refractory chick thymuses induced a net increase of adhesiveness and speed of locomotion. The chemotactic factor secreted by an attractive thymic epithelium was not retained by a 12 kdalton cut-off dialysis membrane, whereas the chemokinetic activity was associated with material of molecular weight higher than 50 kdaltons. Refractory thymuses freed of most of their homopoietic cells became attractive and produced a chemotactic factor of a molecular weight close to 1 kdalton. When introduced into the two separate compartments of the chemotactic chamber, the chemokinetic and the chemotactic activities could complement each other to produce a full response identical to that obtained with attractive thymuses. The two factors, synthesized exclusively by the thymus, were effective on basophilic precursor cells but not on granulocytes. A theoretical model for random cell migration described in the Appendix showed that the standard deviation of the chemotactic index was greatly influenced by the degree of persistence in the direction of movement, the duration and the number of cells recorded. The high values obtained for the standard deviations are fully explained by the persistence in the direction of movement of the basophilic bone marrow cells. In all cases, a clear distinction could be made between a chemokinetic and a chemotactic response. For the first time, a chemotactic mechanism has been demonstrated to control the directed migration of embryonic cells. Our data fully support the hypothesis proposed by Le Douarin (1978, in: Cold Spring Harbor Conferences on Cell Proliferation, pp. 5-31) that the homing of hemopoietic precursor cells into the thymus is controlled by a chemotactic mechanism.

Animals↗

PubMed1998

Expression of CD86 on human marrow CD34(+) cells identifies immunocompetent committed precursors of macrophages and dendritic cells.

Macrophages and dendritic cells derive from a hematopoietic stem cell and the existence of a common committed progenitor has been hypothesized. We have recently found in normal human marrow a subset of CD34(+) cells that constitutively expresses HLA-DR and low levels of CD86, a natural ligand for the T cell costimulation receptor CD28. This CD34(+) subset can elicit responses from allogeneic T cells. In this study, we show that CD34(+)/CD86(+) cells can also present tetanus toxoid antigen to memory CD4(+) T cells. CD86 is expressed at low levels in macrophages and high levels in dendritic cells. Therefore, we have tested the hypothesis that CD34(+)/CD86(+) cells are the common precursors of both macrophages and dendritic cells. CD34(+)/CD86(+) marrow cells cultured in granulocyte-macrophage colony-stimulating factor (GM-CSF)-generated macrophages. In contrast, CD34(+)/CD86(-) cells cultured in GM-CSF generated a predominant population of granulocytes. CD34(+)/CD86(+) cells cultured in GM-CSF plus tumor necrosis factor-alpha (TNF-alpha) generated almost exclusively CD1a+/CD83(+) dendritic cells. In contrast, CD34(+)/CD86(-) cells cultured in GM-CSF plus TNF-alpha generated a variety of cell types, including a small population of dendritic cells. In addition, CD34(+)/CD86(+) cells cultured in granulocyte colony-stimulating factor failed to generate CD15(+) granulocytes. Therefore, CD34(+)/CD86(+) cells are committed precursors of both macrophages and dendritic cells. The ontogeny of dendritic cells was recapitulated by stimulation of CD34(+)/CD86(-) cells with TNF-alpha that induced expression of CD86. Subsequent costimulation of CD86(+) cells with GM-CSF plus TNF-alpha lead to expression of CD83 and produced terminal dendritic cell differentiation. Thus, expression of CD86 on hematopoietic progenitor cells is regulated by TNF-alpha and denotes differentiation towards the macrophage or dendritic cell lineages.

Antigen Presentation↗

PubMed1990

Growth and differentiation of a murine interleukin-3-producing myelomonocytic leukemia cell line in a protein-free chemically defined medium.

We established the continuous growth of WEHI-3B D+ cells in protein-free chemically defined F-12 medium by stepwise decreases in the concentration of fetal calf serum. This cell line, designated as WEHI-3B-Y1, has now been propagated in protein-free F-12 medium for 3 years. The population-doubling time of the cells in culture is about 24 hr. WEHI-3B-Y1 cells are immature undifferentiated cells which show positive staining for naphthol ASD chloroacetate esterase and alpha-naphthyl butyrate esterase and spontaneously exhibit a low level of differentiation to mature granulocytes and macrophages. Medium conditioned by WEHI-3B-Y1 cells stimulated the proliferation of an interleukin-3 (IL-3)-dependent FDCP-2 cell line. This conditioned medium was shown to have erythroid burst-promoting activity when assayed using normal murine bone marrow. The colony formation of WEHI-3B-Y1 cells in semi-solid agar culture was not stimulated by purified recombinant human granulocyte colony-stimulating factor (rhG-CSF). However, in the presence of human transferrin, rhG-CSF enhanced the number of colonies of WEHI-3B-Y1 cells but did not induce their differentiation. These results suggest that WEHI-3B-Y1 cells cultured in protein-free medium produced murine IL-3. In addition, human G-CSF enhanced the clonal growth but did not induce the differentiation of WEHI-3B-Y1 cells cultured in serum-free medium.

Animals↗

PubMed1991

Potential use of human stem cell factor as adjunctive therapy for human immunodeficiency virus-related cytopenias.

Hematopoietic dysfunction with peripheral cytopenias is a common complication of human immunodeficiency virus (HIV) infection. Symptomatic anemia is the most common cytopenia and occurs in the presence and absence of myelosuppressive drug therapy such as zidovudine. Drug-induced neutropenia and immune thrombocytopenia are also frequent and occur in up to 50% of acquired immunodeficiency syndrome (AIDS) patients. Attempts to reduce the impact of bone marrow failure have focused on dose reduction of zidovudine, ganciclovir, and chemotherapy, and the use of recombinant hematopoietic hormones such as erythropoietin (EPO) and granulocyte colony-stimulating factor (G-CSF). Despite these maneuvers, approximately 30% of patients with AIDS receiving zidovudine will become transfusion-dependent. This has led to investigations of other cytokines that may increase blood cell formation. The recent identification of decreased number and proliferation of hematopoietic progenitors in patients with HIV infection suggests that agents which have activity on progenitor cell pools may have clinical utility. We demonstrate that human stem cell factor (HuSCF) increases burst-forming unit-erythroid (BFU-E), colony-forming unit-granulocyte-monocyte (CFU-GM), and CFU-Mix formation in vitro in normal and HIV-infected individuals. HuSCF also decreases the sensitivity of BFU-E to inhibition by zidovudine without altering HIV replication in lymphocytes or monocytes, altering peripheral blood mononuclear cell proliferation to phytohemagglutinin (PHA) and interleukin-2 (IL-2) or altering the effectiveness of zidovudine or dideoxyinosine in inhibiting HIV replication in lymphocytes or monocytes. These studies suggest that HuSCF may have clinical utility in HIV infection as an adjunctive treatment for HIV-related cytopenias.

AIDS-Related Complex↗