Biomedical subjects

I Fabian

Publications and source records attributed to I Fabian.

At least 55 records · Page 3Linked to original sources

PubMed1989

Biological properties in vitro of a combination of recombinant murine interleukin-3 and granulocyte-macrophage colony-stimulating factor.

The effect of recombinant murine interleukin-3 (rIL-3) and recombinant murine granulocyte-macrophage colony-stimulating factor (rGM-CSF) on in vitro murine myeloid progenitor cell (CFU-C) growth and on the function of murine resident peritoneal macrophages was investigated. Both rIL-3 and rGM-CSF are known to support the growth of CFU-C and, when combined, were found to act synergistically to induce the development of an increased number of CFU-C. The distribution pattern of myeloid colonies in the presence of these two growth factors was in general similar to that in the presence of rGM-CSF alone. Both rGM-CSF and rIL-3 enhanced the phagocytosis of Candida albicans (CA) by mature macrophages producing an increase in the percentage of phagocytosing cells as well as an increase in the number of yeast particles ingested per cell. No additive effect on the phagocytosis was observed when the two growth factors were added concurrently. rGM-CSF, but not rIL-3, enhanced the killing of CA by macrophages. This killing was inhibited by scavengers of oxygen radicals.

Animals↗

PubMed1989

Induction of murine macrophage fungal killing by interleukin 3.

The effect of recombinant interleukin 3 (IL-3) on the function of murine resident peritoneal macrophages was investigated. IL-3 enhanced the phagocytosis of Candida pseudotropicalis and Candida albicans and enhanced killing of the former. The enhanced killing is inhibited by scavengers of oxygen radicals, suggesting that IL-3 primes macrophages for enhanced oxidative metabolism in response to Candida.

Animals↗

PubMed1988

The effect of 13-cis retinoic acid on hematopoiesis in human long-term bone marrow culture.

The modulatory effect of 13-cis retinoic acid (RA) on the growth, differentiation and function of hematopoietic cells in human long-term cultures was studied. RA (5 X 10(-8) M) induced enhancement of myeloid progenitor cell growth in the non-adherent layer throughout 6 weeks of incubation while it did not affect the number of myeloid progenitors in the adherent layer. The vitamin did not alter the differentiation pattern of colony forming unit-culture (CFU-C). The addition of RA to cultures for 5 weeks did not alter the cellular composition of the adherent layer. Prolonged exposure of hematopoietic cells to RA did not affect the functional activity of neutrophils and macrophages, i.e. the cells were active in phagocytosing Candida albicans (CA).

Bone Marrow Cells↗

PubMed1988

The effect of deoxycoformycin on bone marrow cells treated with adenosine and deoxyadenosine and hemopoietic growth factors.

Medium conditioned by pokeweed-mitogen-activated human spleen cells enhances the survival of human multipotent stem cells (CFU-mix), erythroid progenitors (BFU-E), and myeloid progenitors (CFU-C) in liquid culture. The effect of adenosine on bone marrow cell survival in liquid culture in the presence of 2'deoxycoformycin and pokeweed-mitogen spleen-conditioned medium was studied. The combination of 2'deoxycoformycin and adenosine was found to have opposite effects on T lymphocytes and hemopoietic progenitors, i.e., the latter were preserved whereas the growth of T lymphocytes was inhibited following prolonged (4-7 days) incubation in suspension culture. The combination of 2'deoxycoformycin and adenosine removed not only all antigenically detectable T cells, but also functionally detectable cells, as judged by response to mitogens. The results suggest that in vitro culture of bone marrow cells in the presence of 2'deoxycoformycin and adenosine might be considered as an alternative way for the removal of T lymphocytes for allogeneic bone marrow transplantation.

Adenosine↗

PubMed1988

Role of pokeweed mitogen spleen conditioned medium in regulating haematopoiesis in long-term human marrow cultures.

The modulatory effect of pokeweed mitogen spleen conditioned medium (PWM-SCM) on the growth of myeloid progenitors (CFU-C) and on the composition of the stromal layer in human bone marrow long-term cultures was studied. In the presence of PWM-SCM there was enhanced CFU-C growth in the adherent layer throughout 6 weeks of incubation, with 2-fold, 2-fold and 3.4-fold increases during wk 2, 4 and 6 respectively (p less than 0.05). In the non-adherent layer of control cultures, however, there was a rapid decline in haematopoiesis which could not be offset by PWM-SCM. The differentiation pattern of CFU-C (entailing monocyte - macrophage progenitors CFU-M, granulocytic progenitors CFU-G or monocyte - granulocyte progenitors CFU-GM) was not altered by PWM-SCM. Fewer lipid-containing cells developed in the adherent layer of cultures treated with PWM-SCM than in control cultures, but the distribution pattern of monocytes - macrophages or granulocytes was not affected. These results suggest that in long-term cultures of human marrow cells there may be extensive haematopoiesis in the presence of PWM-SCM. Whether this is a direct effect on progenitor cells of stimulating factors, or rather of accessory cells in the adherent layer, remains to be clarified.

Bone Marrow Cells↗

PubMed1988

Therapeutic potential of recombinant granulocyte-macrophage colony-stimulating factor and interleukin-3 in murine B-cell leukemia.

The antileukemic activity of murine recombinant granulocyte-macrophage colony-stimulating factor (rGM-CSF) and a combination of rGM-CSF and recombinant interleukin-3 (rIL-3) was examined by using a murine model of spontaneous B-cell leukemia (BCL1) in BALB/c mice. All untreated mice inoculated with 2 x 10(2) BCL1 cells developed leukemia within 4 weeks, with extreme lymphocytosis and a massive increase in both spleen weight and cell number while the number of myeloid progenitors (CFU-C) per spleen was decreased. In contrast, rGM-CSF-or rGM-CSF- and rIL-3-treated recipients did not show any evidence of leukemia or splenomegaly at 4 weeks and showed a significant increase in CFU-C per spleen. Hematologic parameters in the peripheral blood of untreated mice showed anemia and thrombocytopenia. Significant elevations in these parameters were recorded in mice treated with either protocol of CSF. Treatment of recipient mice with either rGM-CSF or rGM-CSF and rIL-3 prolonged their median survival from 6 weeks in untreated controls (range, 5 to 9 weeks) up to the time they were killed at 105 days. Adoptive transfer of spleen cells obtained from mice treated with rGM-CSF, mice treated with a combination of rGM-CSF and rIL-3, and untreated controls, into normal secondary recipients indicated improved survival in recipients inoculated with rGM-CSF. These data indicate that CSFs may inhibit in vivo expansion of leukemic cells of lymphoid origin.

Animals↗

PubMed1987

In-vitro growth and differentiation of marrow cells from myelodysplastic patients in the presence of a retinoidal benzoic acid derivative.

The proliferation and differentiation effects of the synthetic retinoid TTNPB and of 13-cis retinoic acid (RA) on hemopoietic progenitors from bone marrow of myelodysplastic syndrome (MDS) patients were compared. The addition of TTNPB or RA to culture plates containing MDS patient's marrow cells stimulated myeloid colony (CFU-C) growth and caused a significant increase in granulocytic colonies (CFU-G). In the presence of RA the increase in CFU-G was statistically insignificant. Cellular differentiation studies in liquid suspension culture revealed that the two retinoic acid analogues cause a marked decrease in immature granulocytes and an increase in mature granulocytes. There was further an increase in the number of cells that reacted positively with monoclonal antibodies (McAb) binding specifically to granulocytes (B4,3,B13,9 and Leu M4) and a decrease in the percentage of cells reacting with the McAb against Ia-like determinants. These findings indicate that TTNPB is as active as RA in stimulating the growth of hemopoietic progenitors from MDS patients and in enhancing granulocytic differentiation in liquid culture.

Benzoates↗

PubMed1987

Induction of morphological and functional differentiation of human myeloid leukemia cells (HL-60 and LK) by a benzoic acid derivative of retinoic acid.

In previous studies we have shown that the synthetic retinoid (E)-4[2-5,6,7,8-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl-1- propenyl]benzoic acid (TTNPB) stimulates the growth of myeloid progenitors from normal and myelodysplastic patients. In the present study we compared TTNPB with 13-cis-retinoic acid (RA) in its potential to inhibit cell growth and to induce morphological differentiation and functional activity in two cell lines established in vitro from either acute promyelocytic (HL-60) or acute myelomonocytic (LK) patients. Both agents, 10(-6) M, were found to effectively inhibit cell growth and cause a significant decrease in number of immature granulocytes in both cell lines. However, while in HL-60 cells this decrease was associated with a concomitant increase in fully mature granulocytes (neutrophil-like cells) the maturation of LK cells was blocked at the metamyelocyte stage. Study of the functional activity of the induced cells revealed that the rate of superoxide (O-2) production, as assayed by superoxide dismutase-inhibitable ferricytochrome c reduction, was faster in RA treated HL-60 cells than in TTNPB treated cells (0.41 vs. 0.25 nmol. O2-/10(6) cells/60 min). Superoxide production by LK cells treated by either TTNPB or RA was negligible. The percentage of O2(-)-producing cells was determined cytochemically by their ability to reduce the dye nitroblue tetrazolium (NBT). The results showed that production of O2-by LK cells exposed to TTNPB or RA was negligible by this method as well. A higher percentage of HL-60 cells reduced NBT following incubation with RA than with TTNPB (93 +/- 4% vs 26 +/- 2%), but neither of the two retinoids affected the ability of LK cells to reduce NBT. TTNPB thus proved less effective than RA in inducing morphological and functional differentiation in HL-60 cells, whereas in LK cells both agents inhibited cell growth but induced only partial cell differentiation.

Benzoates↗

PubMed1987

The effect of low dose ARA-C on in-vitro haemopoiesis of marrow cells from myelodysplastic patients.

The effect of low dose (10(-12)-10(-7) M) ARA-C on differentiation and proliferation in liquid and semisolid culture of marrow cells from 13 patients with myelodysplastic syndrome (MDS) were studied following incubation in liquid culture with low dose ARA-C. In six of ten patients an increasing number of myeloid cells acquired the morphologic appearance of mature monocyte-macrophages. Increasing number of cells reacted positively to fluoride sensitive naphthyl acetate esterase and specifically bound MY4 monoclonal antibody. Phagocytosis and killing of Candida albicans by monocyte-macrophages incubated with low dose ARA-C was normal and similar to that of the untreated cells. All MDS patients showed reduced myeloid colony and increased cluster formation. Low dose ARA-C had slight but non-significant inhibitory effects on myeloid colony growth. The results indicated that the differentiation pattern of myeloid precursor cells form a subset of MDS patients was altered by exposure to low dose ARA-C in vitro.

Bone Marrow↗

PubMed1987

Myeloid progenitors from the bone marrow of patients with vitamin D resistant rickets (type II) fail to respond to 1,25(OH)2D3.

The active metabolite of vitamin D, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), has been shown to enhance the growth of human granulocyte/macrophage haemopoietic progenitors in vitro and to induce these cells to differentiate along the monocyte/macrophage pathway. In order to evaluate the relationship between specific receptors for 1,25(OH)2D3 and the role of 1,25(OH2D3 in the regulation of haemopoietic cell differentiation, we examined the effect of haemopoietic cell differentiation, we examined the effect of 1,25(OH)2D3 on the in vitro growth and differentiation patterns of marrow myeloid progenitor cells from two patients with 1,25(OH)2D3 resistant rickets, resulting from defective receptors to vitamin D. A significant rise in the frequency of myeloid colonies in control marrow cell cultures was induced by 2 X 10(-9) to 2 X 10(-7)M 1,25(OH)2D3. This rise reached a plateau at 2 X 10(-9)_2 X 10(-8) M 1,25(OH)2D3, resulting in a maximal 54 +/- 9% increase in colony numbers. In contrast, no stimulatory effect could be detected when 1,25(OH)2D3 was added to cultured marrow cells from the patients with 1,25(OH)2D3 resistance. Analysis of colony composition revealed that 2 X 10(-8) and 2 X 10(-7) M, 1,25(OH)2D3 induced a 50 +/- 26% increase in the frequency of colonies composed only of monocytes/macrophages in control, but not in the patients' marrow cell cultures. The effect of 2 X 10(-8) and 2 X 10(-7) M 1,25(OH)2D3 on progenitor cell differentiation towards monocytes/macrophages was also observed in marrow cell suspension cultures. Whereas 1,25(OH)2D3 induced a 81-136% increase in the frequency of monocytes in control marrow cells, no effect could be detected on the generation of mature monocytes in marrow cells of the 1,25(OH)2D3 resistant patients. Our results show that marrow granulocyte/macrophage progenitor cells from patients with 1,25(OH)2D3 resistance fail to respond to 1,25(OH)2D3. We thus demonstrate that the effect of 1,25(OH)2D3 on the proliferation and differentiation of haemopoietic progenitor cells is mediated through its binding to specific cytoplasmic receptors.

Bone Marrow↗

PubMed1987

The effect of 1,25-dihydroxyvitamin D3 on hematopoiesis in long-term human bone marrow cultures.

The modulatory effect of 1,25-dihydroxyvitamin D3 (vit D) on the growth of myeloid progenitors and on the composition of the stromal layer in human bone marrow long-term cultures was studied. Vit D (2 X 10(-8) M) caused an enhancement in myeloid progenitor cell (CFU-C) growth in the nonadherent and adherent layers during the entire 5-week incubation period. The vitamin did not alter the differentiation pattern of CFU-C (monocyte-macrophage progenitors CFU-M, granulocytic progenitors CFU-G, or monocyte-granulocyte progenitors CFU-GM). Vit D caused a marked increase in the percentage of lipid-containing cells in the adherent layer and an increase in the number of cells that specifically bound My4 monoclonal antibody (McAb), that reacted positively to fluoride-sensitive alpha-naphthyl acetate esterase, and that phagocytosed Candida albicans (CA). Concentrated supernatants harvested from control cultures showed significant levels of myeloid colony stimulating factor (CSF) activity. The addition of vit D to cultures for 5 weeks did not alter CSF levels. These results suggest that vit D may play a role in hematopoiesis by acting directly on the progenitor cells or via the stromal cell production of stimulatory factor(s).

Bone Marrow Cells↗

PubMed1987

Biosynthetic granulocyte-macrophage colony-stimulating factor enhances neutrophil cytotoxicity toward human leukemia cells.

Purified biosynthetic (recombinant) human granulocyte-macrophage colony-stimulating factor (GM-CSF) enhances antibody-dependent cell-mediated cytotoxicity (ADCC) of human neutrophils toward human promyelocytic leukemia cells (HL-60), B-lymphoma cells, and human T-leukemia virus II-infected human B-lymphoblastoid cells. The stimulation of antibody-dependent cell-mediated cytotoxicity is rapid (less than an hour), occurs at picomolar concentrations of GM-CSF, and does not require the presence of GM-CSF during the killing reaction. Therefore, neutrophils may be targeted toward tumor cells by antibody and their tumoricidal activity enhanced by GM-CSF in vitro. These results suggest that GM-CSF may have therapeutic utility in cancer therapy by increasing the number and activity of effector cells directed toward tumors by receptors to the immunoglobulin Fc fragment.

Antibody-Dependent Cell Cytotoxicity↗

PubMed1987

Enhanced reconstitution of hematopoietic organs in irradiated mice, following their transplantation with bone marrow cells pretreated with recombinant interleukin 3.

Lethally irradiated C3H/eb mice were injected with syngeneic bone marrow cells that had been exposed for 4 h in vitro to purified bacterially synthesized interleukin 3 (rIL-3). Control mice were injected with cells exposed to incubation medium only. Mice injected with rIL-3-treated cells exhibited, on day 10 after transplantation an 8.2-fold and 2.7-fold increase in number of myeloid progenitors in their spleen and bone marrow, respectively, but the in vitro differentiation pattern of the myeloid progenitors was not affected. There was, however, an increase in the number of cells per individual in vitro myeloid colony (CFU-C) of the rIL-3-treated mice. The latter mice also showed a 1.6-fold increase in the number of splenic colony-forming units (CFU-S), a higher self-renewal capacity of hematopoietic progenitors, and a higher number of leukocytes in the peripheral blood. These results indicate that the injection into lethally irradiated recipients of bone marrow cells briefly pretreated in vitro with rIL-3 significantly enhances the reconstitution of their hematopoietic organs, and suggest that the in vitro pretreatment of bone marrow cells with appropriate stimulating factors could be useful in bone marrow transplantation.

Animals↗

PubMed1987

Effect of 1,25-dihydroxyvitamin D3 and 13-cis-retinoic acid on in vitro hematopoiesis in the myelodysplastic syndromes.

The effect of 2 X 10(-10) to 2 X 10(-7) mol/L 1,25-dihydroxyvitamin D3 (1,25[OH]2D3) and 10(-9) to 10(-6) mol/L 13-cis-retinoic acid on in vitro differentiation and proliferation of marrow cells from patients with myelodysplastic syndrome (MDS) was assessed. Cells from 17 patients were studied by the semisolid technique, and cells from seven patients by both liquid and semisolid cultures. After incubation in liquid culture with 1,25(OH)2D3, in six of seven patients evaluated an increasing number of myeloid cells (185% to 470%) acquired the morphologic appearance of mature monocyte-macrophages, and a decrease in the number of immature myeloid cells (26% to 75%) was observed. Phagocytosis and killing of Candida albicans by monocyte-macrophages incubated with 1,25(OH)2D3 were normal and similar to those processes in untreated cells. 1,25(OH)2D3 increased the percentage of monocytes that phagocytosed C. albicans in three patients. Thirteen of 17 patients showed reduced myeloid cloning, and eight showed increased cluster formation. Cloning efficiency was significantly lower in patients with refractory anemia with excess of blasts and chronic myelomonocytic leukemia. Concentrations of 2 X 10(-9) to 2 X 10(-8) mol/L 1,25(OH)2D3 and 10(-8) to 10(-7) mol/L retinoic acid had a stimulatory effect on myeloid colony growth in five of the six patients with sideroblastic and refractory anemia, but in only two of the 11 patients with refractory anemia with excess of blasts and chronic myelomonocytic leukemia. The results indicate that the differentiation pattern of myeloid precursor cells from a subset of patients with MDS was altered by exposure to 1,25(OH)2D3.

Adolescent↗

PubMed1986

Alteration of antigenic expression of human myeloid precursor cells (CFU-GM) in long-term cultures.

Comparison of myelopoiesis in continuous human bone marrow and cord blood cultures was performed. The presence of major histocompatibility complex (MHC) antigens on myeloid precursors (CFU-GM) from cord blood was confirmed using monoclonal antibodies (MoAb) defining class I (i.e., anti-beta 2-microglobulin (B2, MG1) anti-HLA-A,B heavy chain (W6/32), and anti-HLA locus B(4E), and class II (HLA-DR (7,2] antigens. The effect of long-term culture on the expression of these antigens was investigated. Our studies indicate that following prolonged in vitro culture there is a decrease in the expression of MHC antigens on CFU-GM. Our observations provide a rationale for considering the use of cord blood leukocytes subjected to long-term culture as an alternative to allogeneic hematopoietic cell transplantation.

Aging↗

PubMed1986

Differentiation of bone marrow cells from myelodysplastic patients in the presence of 1,25 dihydroxyvitamin D3 or 13-cis retinoic acid.

The separate effects of vitamin D3 (1,25(OH)2D3) and 13-cis retinoic acid on the differentiation in liquid culture of marrow cells from seven patients with myelodysplastic syndrome (MDS) were studied. Following incubation with 1,25(OH)2D3, an increasing number of myeloid cells acquired the morphological appearance of mature monocyte-macrophages and reacted positively to fluoride-sensitive naphthyl acetate esterase and specifically bound My4 monoclonal antibody (McAb). Incubation of bone marrow cells with 13-cis retinoic acid enhanced the number of cells with the morphological appearance of metamyelocytes and mature granulocytes as well as those that reacted positively with AS-D naphthol chloroacetate esterase. The results suggest that the differentiation pattern of myeloid precursor cells from MDS patients can be modulated by 1,25(OH)2D3 and 13-cis retinoic acid.

Aged↗

PubMed1986

Effect of cytosine arabinoside on differentiation of normal human bone marrow cells.

Human normal bone marrow cells were evaluated for alteration of differentiation after exposure for seven days to 10(-12)-10(-9) M cytosine arabinoside (ARA-C) in liquid culture. An increased number of induced cells had the morphologic appearance of mature monocytes-macrophages; they adhered to petri dishes, reacted positively to fluoride-sensitive naphthyl acetate esterase, and specifically bound My4 monoclonal antibody (MCAb). Assessment of phagocytosis and killing of Candida albicans (CA) by cultured monocytes-macrophages exposed to ARA-C demonstrated that treated cells had the same capacity to phagocytose and kill CA as did untreated cells. In semisolid culture, low doses of ARA-C did not affect myeloid colony growth. These studies indicate that ARA-C enhances monocytic differentiation of normal human bone marrow cells in liquid culture.

Bone Marrow↗

PubMed1986

Effect of 1,25 dihydroxyvitamin D3 and retinoic acid on normal human pluripotent (CFU-mix), erythroid (BFU-E), and myeloid (CFU-C) progenitor cell growth and differentiation patterns.

The modulatory effect of 1,25 dihydroxyvitamin D3 (vit D) and 13 cis retinoic acid (retinoic acid) on the growth and differentiation of normal human pluripotent stem cell, erythroid, and myeloid progenitor cell growth was studied using semisolid methylcellulose clonal assay. Dose response curves showed that maximal increments of myeloid colony (CFU-C) growth (150%) occurred with vit D at 2 X 10(-9) -2 X 10(-8) M and with retinoic acid (184%) at 1 X 10(-7) M. Vit D caused a 134% increase in macrophage colonies (CFU-M) and a decrease in granulocytic (CFU-G) and granulocyte-macrophage colonies (CFU-GM) (50% and 58%, respectively, as compared to the control). Retinoic acid did not alter the differentiation pattern of myeloid colonies (CFU-M, CFU-G, and CFU-GM). Vit D at 2 X 10(-8) M had an inhibitory effect on BFU-E (62% growth of control) and did not affect CFU-mix growth. Retinoic acid at 10(-7) M did not alter the growth of either BFU-E or of CFU-mix. Cellular differentiation studies in liquid suspension showed that vit D caused a 213% increase in monocyte-macrophages and a 56% and 26% decrease in immature and mature granulocytes, respectively. Retinoic acid caused a marked (79%) decrease in immature granulocytes whereas the percentage of mature granulocytes and monocyte-macrophages was not changed. Assessment of phagocytosis and killing of Candida albicans (C.A.) by cultured monocyte-macrophages and granulocytes exposed to vit D and retinoic acid demonstrated that treated cells had the same capability to phagocytose and kill C.A. as did untreated cells.

Bone Marrow Cells↗