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Biomedical subjects

A Porcellini

Publications and source records attributed to A Porcellini.

At least 91 records · Page 5Linked to original sources
PubMed1984

Allogeneic marrow transplantation for thalassemia.

Thirteen patients with homozygous beta thalassemia underwent allogeneic marrow transplantation from sibling donors, 12 of whom were heterozygous for beta thalassemia. Six patients were transplanted in an advanced stage of their disease while seven were transplanted early in their disease course. Donors and recipients were genotypically identical for the HLA-A, -B and -D loci in 11 cases and mismatched for the D locus in two. A variety of preparative regimens was utilized involving high doses of busulphan (Bu) and/or cyclophosphamide (CY) and/or total body irradiation (TBI). Failure of engraftment or autologous hematologic recovery after transient engraftment was seen after intensive preparative regimens including: CY 200 mg/kg and 800 rad of TBI; Bu 8 mg/kg and CY 200 mg/kg; and Bu 8 mg/kg, CY 200 mg/kg, and 300 rad of TBI. A regimen of Bu 16 mg/kg, CY 200 mg/kg, and 400 rad of TBI resulted in deaths from transplant-related causes in the three patients treated with this regimen. Seven of the 13 patients are surviving 363-665 days after transplant. Five of the seven failed to achieve engraftment or had autologous reconstitution after transient engraftment. Five of the six deaths were transplant related, and one patient died of cardiac failure one year after an unsuccessful transplant attempt. Two patients are surviving with engraftment and without thalassemia major 363 and 491 days after transplantation. Both of these patients were transplanted early in their disease course.

Adolescent↗
PubMed1984

Effect of two cyclophosphamide derivatives on hemopoietic progenitor cells and pluripotential stem cells.

The studies described herein were undertaken to help define the effects of certain cyclophosphamide derivatives that have been used for selective removal of leukemic cells from marrow samples used for autologous transplantation. We have tested the effect of 4-HC and another cyclophosphamide congener, ASTA-Z 7557, on pluripotent stem cells (CFU-S) and committed progenitor cells (CFU-GM) in mice. The CFU-S were evaluated by the spleen colony assay at eight days and 12 days after transplant. The eight-day colonies are transient in nature, rapidly growing, mainly erythroid, and lack pluripotential precursors. The 12-day colonies are believed to provide a measure of hemopoietic stem cells as they slowly grow and do contain primitive precursors. Our data show that at the maximum dose levels tested, both drugs caused a 100% loss of CFU-GM and about 80%-95% inhibition of early transient CFU-S. In contrast, about 70% of the pluripotent 12-day CFU-S were spared. These data appear to explain the hemopoietic recovery seen in man after transplantation with marrow cells treated with 4-HC despite their relative absence of hemopoietic progenitor cells.

Animals↗
PubMed1983

Ontogeny of granulocyte-macrophage progenitor cells in the human fetus.

The CFU-Gm content of liver, spleen and bone marrow of human fetuses was determined from the 8th to 28th week of gestational age. The study of progenitor cells from 43 fetal livers revealed that the CFU-Gm increased from 8 to 12 weeks, was relatively stable through 16 weeks and thereafter declined by 22 to 24 weeks. The total number of liver CFU-Gm rose from 10(4) to greater than 10(6) CFU-Gm by the 16th week of gestation and declined to approximately 4 X 10(5) progenitor cells by 22 to 24 weeks. Peak values of bone marrow CFU-Gm were noted at 10 to 14 weeks of gestation. Generally, the numbers of these progenitor cells declined by 16 to 18 weeks; however, several high values were obtained at later times. Splenic CFU-Gm were relatively constant in number between 12 and 28 weeks of gestation with no correlation with fetal age. Thus, these studies indicate that certain fetal tissues contain substantial numbers of hemopoietic progenitor cells. Based on the quantity of CFU-Gm obtained, it appears feasible to use fetal liver cells as a source of progenitor cells for transplantation.

Bone Marrow↗
PubMed1983

Identification of hemopoietic cells responsive to colony-stimulating factor by autoradiography.

Binding of radiolabeled L-cell colony-stimulating factor (CSF) was studied using murine bone marrow and fetal liver cells. With 10(7) cells, saturation of binding was seen with approximately 500,000 cpm of 125I-CSF. Minimal binding was detected after one hour incubation with tracer at 37 degrees C; however, marked cellular uptake of radioactivity was noted after 24-hr exposure to CSF. As judged by autoradiographs, small numbers of myeloblasts, promyelocytes, and large mononuclear cells were labeled with 1-hr exposure to tracer. By 6 hr of incubation, 50%-70% of myeloblasts and promyelocytes and small numbers of late granulocytic cells were labeled. Virtually all myeloblasts and promyelocytes and approximately 50% of myelocytes, metamyelocytes, polymorphonuclear granulocytes, and monocytes were labeled after 24-hr exposure to the radioiodinated CSF. Label was not detected on erythroblasts, eosinophils, or megakaryocytes. Suspensions of fetal liver cells had lower uptake of radioactivity than bone marrow cells. This appeared to result from a lesser concentration of granulocytic cells in fetal liver, as labeling of individual cells was similar with both tissues. In additional experiments, CSF binding to marrow cells was assessed after 30-min exposure to tracer at 0 degrees C. Uptake of 125I-CSF exceeded that observed after 24-hr incubation at 37 degrees C. With this technique, cellular label was also confined to granulocytic and monocytic cells. These findings suggest that purified CSF reacts with and may stimulate immature and mature cells of the granulocytic and monocytic lineages.

Animals↗
PubMed1982

Fetal liver transplantation in 2 patients with acute leukaemia after total body irradiation.

2 patients with acute leukaemia in relapse were transplanted with fetal liver cells following a conditioning regimen of cyclophosphamide (120 mg/kg) and total body irradiation (1000 r). Each patient achieved a remission with haematopoietic recovery that was rapid in one case and delayed in the other. In one case there was evidence of chimerism as demonstrated by the presence of the XYY karyotype of the donor fetus in 20% of marrow metaphases, by the presence of double Y bodies in the peripheral blood, by the appearance of new HLA-antigens, and by red cell isoenzyme phenotypes of donor origin. In the second case there was prompt haematopoietic recovery and the appearance of red cell isoenzyme phenotype of donor origin. Survival was 153 and 30 d, respectively, and both patients died of interstitial pneumonia without evidence of graft versus host disease.

Acute Disease↗
PubMed1982

Electron microscopy of human fetal erythroid cells before and after cryopreservation.

Fetal erythropoiesis was studied in human livers at 10 to 12 weeks of gestation. The most primitive blood cells were often observed in large indentations of the surface of hepatocytes and the plasma membranes of the two cell types were adherent at sites of attachment. Erythroid cell maturation occurred predominantly in the lumen of the sinusoids. Cell suspensions obtained from fetal livers were centrifuged, frozen at -196 degrees C, thawed and studied by electron microscopy. The primitive cells were morphologically altered by these procedures. Changes included damage to mitochondria and cell membranes and vacuole formation. Erythroblasts, by comparison, were virtually intact and even displayed some indications of reestablished functions within 10 minutes after thawing.

Cell Communication↗
PubMed1981

The effects of calusterone on hemopoiesis in mice after busulfan-induced suppression of hemopoietic stem cells.

Studies were undertaken in mice to determine the effect of calusterone (a weakly androgenic steroid) on hemopoiesis. Animals were myelosuppressed with a single injection of the alkylating agent busulfan and subsequently treated with varying courses of calusterone. Simultaneous injection of calusterone did not prevent the rapid decline in CFU-S or CFU-C. Daily administration of calusterone for 12 to 14 days after busulfan had little influence on bone marrow cellularity; however, a twofold increase in peripheral blood neutrophils was observed. Bone marrow CFU-S and CFU-C were twofold to threefold higher after 8 to 14 days of treatment with calusterone, but there were no progressive increments in these hemopoietic stem cells during this time interval. In contrast to the granulocyte series, erythroid recovery was rapid after busulfan. Marrow erythroid precursors and CFU-E returned to normal levels by day 8. Daily treatment with calusterone accelerated recovery and led to an overshoot in these parameters of marrow erythropoiesis. Although an early course of calusterone treatment had only modest effects on CFU-S and CFU-C, delayed treatment was clearly stimulatory. A 10-day course of calusterone from days 14 to 24 after busulfan increased bone marrow CFU-S and CFU-C from 5% to 23% of controls to near normal values. Thus calusterone appears to stimulate all classes of hemopoietic progenitor cells. Its effects after busulfan are highly time-dependent, with greatest activity observed in those cellular compartments undergoing proliferative expansion.

Animals↗
PubMed1981

[The use of autologous bone marrow transplants in malignant hemopathies and solid tumors].

Bone marrow collected from patients with hematologic malignancies were cryopreserved using DMSO as a cryoprotective agent. The growth kinetics of hemopoietic stem cells frozen to -196 degrees C were monitored immediately after thawing by the semisolid agar CFU-C assay and 2 different methods of cell reconstitution were compared. In the first way, thawed cells were plated after the removal of DMSO by washing the cell suspension, in the second, cell suspensions were cultured after a simple 1:1 dilution of DMSO with medium. The number of CFU-C per 2 X 10(5) cells plated was higher washing out the DMSO in all the groups studied. However, the absolute numbers of CFU-C contained in the whole ampoules after the freezing procedures was approximately the same with both methods. It is concluded that washing the cells only apparently yielded a better cloning efficiency, suggesting that such a procedure led to a higher mature nucleated cell loss with the consequence of a CFU-C concentration. This trend seems particularly evident in the AML and CML patients.

Bone Marrow Transplantation↗
PubMed1979

[Effect of calusterone on the stem cell compartment after suppression with busulfan in mice].

These studies were undertaken to evaluate the effect of Calusterone (a weakly androgenic steroid) on hemopoiesis in mice. Cellular proliferation was suppressed by a single (IP) injection of busulfan (BU) (40 mg/Kg). Calusterone (CA) was administered s.c. SC daily (10 mg/Kg); controls received an equivalent injection of oil vehicle. Hemopoiesis was characterized by measurement of peripheral blood neutrophils, bone marrow cellularity, differentials and stem cell content. This included pluripotent (CFU-S), granulocytic (CFU-C) and erythroid (CFU-E) progenitor cells. Only a minimal decrease in narrow cellularity was observed after busulfan; similar values were obtained in calusterone recipients. Neutrophils fell by day 4, showed an abortive rise on day 8 and subsequently fell to 32% of control values. Calusterone recipients showed a 2 fold higher value (62%) on day 12. CFU-S, CFU-C, and CFU-E were depressed to 20-40% of control values by day 2 after busulfan. Although CFU-S and CFU-C remained depressed through the 14th day, CFU-E recovered by day 8 CA stimulated an overshoot in these cells to 288% of control values. These findings correlated with an increase in marrow erythroid cells to 182% on day 10. CFU-S remained low (20%) by day 14 and gradually increased to 50% of control by day 24. A delayed 10 day course of CA more than doubled the CFU-S recovery. These findings show that BU markedly suppress hemopoietic stem cells: a differential recovery is noted between CFU-E and the other progenitor cells. CA increase the recovery of all 3 hemopoietic stem cell compartments when given either immediately or in a delayed schedule. This suggests that this compound may be of use in the therapy of bone marrow hypoplasia.

Animals↗