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L Grassia

Publications and source records attributed to L Grassia.

7 recordsLinked to original sources

Influence of marrow CFU-GM content on engraftment and survival after allogeneic bone marrow transplantation.

The influence of the CFU-GM content of donor marrow on the outcome of allogeneic marrow transplantation (BMT) has been debated. We now report 38 patients (25 acute leukemias, 10 chronic myeloid leukemias, two myeloma; 24 in first CR/CP and 14 in more advanced phases of their disease) undergoing unmanipulated HLA-identical sibling BMT following conditioning with cyclophosphamide and total body irradiation (TBI). The median number of nucleated cells infused was 4.3 x 10(8)/kg (range 1.5-8.4); median CFU-GM numbers were 2.4 x 10(4)/kg (range 0.1-46). End-points of the study were (1) speed of neutrophil and platelet engraftment; (2) quality of engraftment beyond day +50 after BMT; and (3) transplant-related mortality in patients stratified according to whether they had received less than (n = 18) or more than (n = 20) 2.4 x 10(4)/kg CFU-GM. These two groups were comparable for diagnosis, disease status, donor sex, donor age, recipient sex, recipient age, CVHD prophylaxis, number of cells infused and CMV serology. Neutrophil counts were comparable at all time intervals. There was also no difference in platelet counts on days +7 to +50. However, patients who had received higher CFU-GM numbers had significantly higher platelet counts on day +80 (149 vs. 75 x 10(9)/L; P = 0.002), day +100 (153 vs. 77 x 10(9)/L; P = 0.0009) and day +150 (179 vs. 95 x 10(9)/L; P = 0.01). The 2-year actuarial transplant-related mortality was 5% vs. 53% (P = 0.007) in patients receiving high or low numbers of CFU-GM.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

In vitro effect of stem cell factor on colony growth from acquired severe aplastic anemia.

In this study we review our present understanding of the effect of stem cell factor (SCF) on the in vitro growth of hemopoietic progenitors from patients with acquired severe aplastic anemia (SAA). We have run three separate sets of experiments. First, we have tested the expression of receptor mRNAs for granulocyte-macrophage colony stimulating factor/interleukin 3 (GM-CSF/IL-3) and for c-kit protein on bone marrow (BM) cells from SAA patients. Molecular analysis revealed the presence of normal transcripts for alpha and beta chains of GM-CSF/IL-3 receptor and for c-kit protein by Northern blot analysis. Second, we have tested the in vitro response to SCF of BM cells derived from 11 SAA patients: SCF induced a significant enhancement of erythroid burst forming unit (BFU-E) growth (8 to 29, p = 0.01) and allowed the formation of granulocyte/erythroid/macrophage/megakaryocyte (GEMM) colonies which were not scored in baseline culture conditions (0 to 8, p = 0.01). Granulocyte-macrophage colony forming unit (CFU-GM) growth was also enhanced (4 to 20, p = 0.3). This was true for patients both at diagnosis and after antilymphocyte globulin (ALG) treatment. We concluded that SCF can promote the in vitro growth of hemopoietic progenitors in patients with acquired SAA. Third, we have tested the response to SCF of peripheral blood (PB) hemopoietic progenitors collected from patients receiving in vivo long-term treatment with granulocyte CSF (G-CSF). When PB cells were plated directly in the presence of GM-CSF there was no colony formation.(ABSTRACT TRUNCATED AT 250 WORDS)

Anemia, Aplastic↗

Long-term hyposensitization and adverse immunologic responses. A laboratory evaluation.

Ninety atopic patients with allergic asthma and/or rhinitis were classified into three groups: group A, consisting of 30 patients never subjected to immunotherapy; group B, 30 patients receiving immunotherapy for various allergies for 3 to 24 months; group C, 30 patients receiving immunotherapy for 5 or more years. The following studies were performed using standard techniques: quantitative determination of serum immunoglobulin concentrations IgA, IgG, IgM, rheumatoid factor, C3 and C4 concentrations, antinuclear antibodies (ANA). Circulating immune complexes were detected by a competitive immuno-enzyme assay. No statistical differences were found in the groups studied for every parameter considered. Although signs and symptoms of autoimmune disease were not present, an elevated incidence of ANA in the entire group (23.3%) was found.

Adolescent↗

Early hemopoietic progenitors in the peripheral blood of patients with severe aplastic anemia (SAA) after treatment with antilymphocyte globulin (ALG), cyclosporin-A and G-CSF.

BACKGROUND AND OBJECTIVE: We previously reported that patients with acquired severe aplastic anemia (SAA) treated with antilymphocyte globulin (ALG), 6-methylprednisolone, cyclosporin A (CyA) and granulocyte colony-stimulating factor (G-CSF) can mobilize peripheral blood hemopoietic progenitors (PBHP). The aim of the present study was to assess phenotypic and functional properties of these PBHP. METHODS: We studied seven patients who underwent 43 leukophereses (median 5) between day +30 and +80 following ALG, while in treatment with CyA and G-CSF. Mobilized peripheral blood hemopoietic progenitors were analyzed using surface markers, conventional assays for clonogenic cells (CFU-GM, BFU-E, CFU-GEMM) as well as the recently developed assay for long-term culture initiating cells (LTC-ICs). RESULTS: The proportion of CD34+ cells ranged between 0% and 5.4% (median 0.3%), CD34+DR between 0% and 3.5% (median 0.1%) and CD8+ cells between 3.3% and 56% (median 31%). When light density mononuclear cells (MNC) were plated in vitro, we could grow colony-forming units-granulo-macrophage (CFU-GM) (range 0-45/10(5) MNC; normal controls 21-200/10(5) MNC), burst-forming units-erythroid (BFU-E) (range 0-5/10(5) MNC; normal controls 0-6/10(5) MNC), multipotent colonies (CFU-GEMM) (range 0-3/10(5) MNC; normal controls 0-6/10(5) MNC) and high proliferative potential colony-forming cells (HPP-CFC) (range 0-3.4/10(5) MNC). We studied long-term culture-initiating cells (LTC-ICs) in 18 leukophereses from 4 patients; in 7/18 samples LTC-ICs were grown at low frequency (range 0.4-2/10(6) MNC) (normal controls 5-130/10(6) MNC), and in one patient in the absence of CFU-GM growth. The total yield of LTC-ICs in two patients was 7.64 and 10.5 x 10(2)/kg of body weight. INTERPRETATION AND CONCLUSIONS: This study suggests that cells with the phenotype and in vitro function of early hemopoietic progenitors are found, though in small numbers, in the peripheral blood of patients with SAA after treatment with immunosuppressants and prolonged G-CSF administration. Whether G-CSF-mobilized progenitors contribute to hemopoietic recovery in these patients remains to be determined.

Adolescent↗