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Biomedical subjects

Roberto M Lemoli

Publications and source records attributed to Roberto M Lemoli.

24 records · Page 2Linked to original sources
PubMed2003

Autologous transplantation of granulocyte colony-stimulating factor-primed bone marrow is effective in supporting myeloablative chemotherapy in patients with hematologic malignancies and poor peripheral blood stem cell mobilization.

We assessed the hematopoietic recovery and transplantation-related mortality (TRM) of patients who had failed peripheral blood stem cell mobilization and subsequently received high-dose chemotherapy supported by granulocyte colony-stimulating factor (G-CSF)-primed bone marrow (BM). Studied were 86 heavily pretreated consecutive patients with acute leukemia (n = 21), refractory/relapsed non-Hodgkin lymphoma (n = 41) and Hodgkin disease (n = 17), and multiple myeloma (n = 7). There were 78 patients who showed insufficient mobilization of CD34+ cells (< 10 cells/microL), whereas 8 patients collected less than 1 x 106 CD34+ cells/kg. BM was primed in vivo for 3 days with 15 to 16 microg/kg of subcutaneous G-CSF. Median numbers of nucleated cells, colony-forming unit cells (CFU-Cs), and CD34+ cells per kilogram harvested were 3.5 x 10(8), 3.72 x 10(4), and 0.82 x 10(6), respectively. Following myeloablative chemotherapy, median times to achieve a granulocyte count higher than 0.5 x 10(9)/L and an unsupported platelet count higher than 20 and 50 x 10(9)/L were 13 (range, 8-24), 15 (range, 12-75), and 22 (range, 12-180) days, respectively, for lymphoma/myeloma patients and 23 (range, 13-53), 52 (range, 40-120), and 90 (range, 46-207) days, respectively, for leukemia patients. Median times to hospital discharge after transplantation were 17 (range, 12-40) and 27 (range, 14-39) days for lymphoma/myeloma and acute leukemia patients, respectively. TRM was 4.6%, whereas 15 patients died of disease. G-CSF-primed BM induces effective multilineage hematopoietic recovery after high-dose chemotherapy and can be safely used in patients with poor stem cell mobilization.

Adolescent↗
PubMed2003

Generation of dendritic cells from CD14+ monocytes positively selected by immunomagnetic adsorption for multiple myeloma patients enrolled in a clinical trial of anti-idiotype vaccination.

Circulating monocytes from multiple myeloma patients enrolled in a clinical study of anti-idiotype vaccination were labelled with clinical-grade anti-CD14 microbeads and positively selected with the CliniMACS instrument. Cells were then grown, according to good manufacturing practice guidelines, in fetal-calf-serum-free medium in cell culture bags and differentiated to dendritic cells (DC) with granulocyte-macrophage colony stimulating factor plus interleukin 4 (IL-4), followed by either tumour necrosis factor-alpha (TNF-alpha) or a cocktail of IL-1beta, IL-6, TNF-alpha and prostaglandin-E2. The CD14+ cell yield was increased from 17.6 +/- 6.5% to 93.8 +/- 6.3% (recovery 64.4 +/- 15.4%, viability > 97%). After cell culture, phenotypic analysis showed that 86.7 +/- 6.8% of the cells were DC: 2.27 +/- 0.9 x 108 DC/leukapheresis were obtained, which represented 20.7 +/- 4.6% of the initial number of CD14+ cells. Notably, the cytokine cocktail induced a significantly higher percentage and yield (28.6 +/- 3% of initial CD14+ cells) of DC than TNF-alpha alone, with secretion of larger amounts of IL-12, potent stimulatory activity on allogeneic T cells and efficient presentation of tumour idiotype to autologous T cells. Storage in liquid nitrogen did not modify the phenotype or functional characteristics of preloaded DC. The recovery of thawed, viable DC was 78 +/- 10%. Finally, interferon-alpha-2b was at least as efficient as IL-4 in inducing the differentiation of mature, functional DC from monocytes.

Antibodies, Anti-Idiotypic↗
PubMed2003

Functional and kinetic characterization of granulocyte colony-stimulating factor-primed CD34- human stem cells.

We assessed the functional properties and the kinetic status in vitro, and the engraftment potential in vivo of human haematopoietic stem cells according to the expression of CD34 antigen. Lin-CD34- and Lin-CD34+ cells were isolated from granulocyte colony-stimulating factor-primed peripheral blood (PB) cells of healthy donors. The CD34- cell fraction did not contain either clonogenic cells in semisolid culture or long-term culture initiating cells (LTC-IC). However, stroma-dependent liquid cultures and cytokines induced CD34 expression on a minority of stem cells, acquisition of clonogenic capacity and generation of LTC-IC. Significantly higher percentages of quiescent G0 cells and lower percentages of cycling G1 cells were found in Lin-CD34- cells when compared with Lin-CD34+ cells. Kinetic quiescence of Lin-CD34- cells was associated with a significantly higher expression of the negative regulators of the cell cycle, p27Kip1 and p21(cip1/waf1). Cytokine-mediated induction of CD34, in vitro, resulted in cycling of stem cells and downregulation of p27. There was a higher rate of human long-term engraftment in immunocompromised non-obese diabetic (NOD)/recombination activating gene 1null and NOD/severe combined immunodeficient-beta2microglobulin(null) mice injected with CD34+ cells. Thus, our study indicated that CD34 expression on human PB stem cells was associated with haematopoietic activity, cell-cycle recruitment and downregulation of p27Kip1 in vitro and higher engraftment capacity in vivo.

Animals↗
PubMed2002

Dendritic cells are functionally defective in multiple myeloma: the role of interleukin-6.

We studied concentration, phenotype, and function of peripheral blood (PB) dendritic cells (DCs) from patients with multiple myeloma (MM). The absolute number of circulating precursors of myeloid and plasmacytoid DCs was significantly lower in MM patients than in healthy subjects. After maturation, PBDCs from MM patients showed significantly lower expression of HLA-DR, CD40, and CD80 antigens and impaired induction of allogeneic T-cell proliferation compared with controls. Remarkably, they were not capable of presenting the patient-specific tumor idiotype to autologous T cells. Conversely, DCs generated in vitro from CD14(+) monocytes from the same patients, and PBDCs freshly isolated from healthy donors efficiently stimulated allogeneic and autologous T cells. To clarify the mechanism of PBDC deficiency in MM, we investigated the effects of the main plasma cell growth factor, interleukin-6 (IL-6), on the development of DCs from CD34(+) cells. IL-6 inhibited the colony growth of CD34(+) DC progenitors and switched the commitment of CD34(+) cells from DCs to CD14(+) CD1a(-) CD86(-)CD80(-) CD40(+/-)HLA-DR +/- monocytic cells exerting potent phagocytic activity but no antigen-presentation capacity. This effect was reversed by anti-IL-6 antibodies. Growing CD34(+) cells in the presence of autologous serum (without IL-6) also suppressed the development of functional DCs. This study demonstrates that PBDCs from MM patients are functionally defective, partially because of IL-6-mediated inhibition of development. This brings into question the advisability of using PBDCs as antigen carriers for immunotherapy trials in MM. The results also suggest a novel mechanism whereby myeloma cells escape immune recognition.

Antigen Presentation↗
PubMed2002

Interleukin-11 induces proliferation of human T-cells and its activity is associated with downregulation of p27(kip1).

BACKGROUND AND OBJECTIVES: We have recently shown that interleukin (IL-)11 induces polarization of human T-cells by inhibiting macrophage production of IL-12 and by exerting a direct effect on CD4+ T-cells. In this study, we investigated the effects of IL-11 on the kinetic activation and apoptosis of T-cell subsets stimulated with anti-CD3/CD28 antibodies, anti-CD3 and IL-2 or dendritic cells. DESIGN AND METHODS: Apoptosis and cell cycle analysis of T-cells were assessed by double staining with propidium iodide and intracellular Ki-67 and by acridine orange staining. The expression of the negative regulator of the cell cycle p27Kip1 (p27) was also determined by flow cytometry. RESULTS: Our results show that 18 hours of incubation with IL-11 resulted in a significantly higher number of cycling CD4+ cells, CD4+CD45RA+ naive T-cells and CD4+CD45RO+ memory T-cells, but not of CD8+ cells. The kinetic activity of IL-11 was observed up to 72 hours, when the peak value of S-phase cells occurred. IL-11 also significantly enhanced CD4+ and CD4+CD45RA+ cell proliferation when T-cells were co-incubated with allogeneic dendritic cells. Conversely, IL-11 did not protect any of the T-cell subsets from apoptosis. At the functional level, a type-2 cytokine pattern of cultured T-lymphocytes was observed after 5 days of incubation with IL-11. Proliferation and functional activation of T-cells were preceeded by downregulation of p27, which occurred as early as 12 hours after incubation with IL-11. INTERPRETATION AND CONCLUSIONS: IL-11 induces Th-2 polarization and cell-cycle entry of human CD4+, CD4+CD45RA+ and CD4+CD45RO+cells and their activation is associated with the downregulation of p27.

Apoptosis↗