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J Milosevits

Publications and source records attributed to J Milosevits.

8 recordsLinked to original sources

[T-cell large granular lymphocytic leukemia associated with pure red cell aplasia, successfully treated with cyclophosphamide].

Authors report effective treatment of T-cell large granular lymphocyte (LGL) leukaemia and secondary pure cell aplasia with cyclophosphamide. The current classification of LGL proliferations is presented, with emphasis on the issues of diagnosis, clinical course and treatment. LGL proliferations are not so rare that previously thought and should be involved in the differential diagnosis of neutropenia, pure red cell aplasia, Felty's syndrome and vasculitis of unknown origin.

Antineoplastic Agents, Alkylating↗

Comparison of the lymphoid toxicities of mitobronitol and busulphan in mice: reduced B cell toxicity and improved thymic recovery as possible contributors to the reduced risk for complications following BMT with mitobronitol preconditioning.

It has previously been reported that the use of mitobronitol (dibromomannitol, DBM) instead of busulphan (BU) for myelosuppression is associated with significantly decreased risk for several complications of allogeneic bone marrow transplantation in accelerated chronic granulocytic leukemia. In exploring the pharmacologic basis for this observation, we have compared the acute and subacute cytotoxicities of DBM and BU on the spleen and thymus of mice. While there was comparable early (day 3) weight loss in both organs following these treatments, splenic B cells exhibited significantly less damage, and thymic regeneration (over weeks) was significantly faster following DBM treatment than with BU. These observations raise the possibility that improved post-BMT immune recovery could contribute to the clinical benefits observed with DBM-preconditioning.

Animals↗

Lymphocyte subset reconstitution after allogeneic bone marrow transplantation using radiation-free conditioning regimen for patients with chronic granulocytic leukemia.

Conditioning regimens for BMT are important in determining transplant outcome. A radiation-free protocol containing Mitobronitol (DBM), Cytarabine (Ara-C) and Cyclophosphamide (Cy) was used for conditioning of patients with chronic granulocytic leukemia (CGL). Using this conditioning treatment, fewer transplant related complications, including acute GVHD, VOD and severe infections, were observed. Acute GVHD did not develop, but chronic GVHD, accompanied with graft-versus leukemia, was present in half of the cases. To determine the clinical effect of the DBM/Ara-C/Cy conditioning, the recovery of peripheral blood lymphocytes was examined after allogeneic BMT for patients with CGL in comparison with TBI/Cy conditioning. The lymphocyte subsets of 11 DBM patients were followed and analyzed periodically (30-90 days, 4-12 months and > 13 months) using ten monoclonal antibodies and flow cytometry. Decreased percentage of total T cells as well as CD4+ and CD8+ subpopulations, significantly decreased T cell activation and increased proportion of TCR gamma delta + cells were found to be characteristic in the early post-transplant period in the DBM group. Early recovery and consistently higher percentage of B cells were observed for the whole follow-up period of patients receiving DBM conditioning. A high proportion of NK cells was observed in all transplant recipients. These findings suggest that the characteristic pattern of recovering lymphocytes is associated with the lack of severe transplant-related clinical complications following DBM/Ara-C/Cy conditioning.

Adolescent↗

Immunophenotypic and functional characteristics of haemopoietic cells from human cord blood.

Cord blood (CB) as a new source for bone marrow transplantation represents advantageous features concerning stem cell and leucocyte compartments and function. We attempted to get more information about the phenotypes and function of CB cells by investigating their cell surface markers and also the production of IL-2, IFN-gamma and IL-6 by mitogen and alloantigen stimulation. The CB cells were characterized by a low proportion of CD3+ T cells, CD4+ T subpopulation, activated T cells and CD3+CD16/CD56+ cytotoxic cells, suggesting reduced graft versus host potential. The significant increase of CD19/CD3 double positive cells and decrease of CD19/HLA-DR double positive mature B cells reflect that immature B cells exist in CB. In the functional studies, a 27- and 5-fold reduction was observed in the production of IFN-gamma by CB cells stimulated with PHA and allogeneic cells, respectively. The production of IL-2 in PHA-stimulated CB cells also showed a 50% determination. Decrease in the production of these cytokines by CB cells is supported by the decline of the proportion of CD3+ T cells. However, an increase was observed in the production of IL-6 by CB cells stimulated with allogeneic cells as compared with the controls. These results suggest a difference in the functional activity of the T helper cell subsets between the CB and peripheral blood and/or differences in the functional maturity of T helper cell subsets and B cells in these compartments.

Cells, Cultured↗

Changes in adhesion molecule expression and function in B-cell chronic lymphocytic leukaemia after in vitro interferon-alpha stimulation.

Peripheral blood mononuclear cells (PBMCs) from 10 B-CLL patients were investigated after 24 hours of in vitro interferon-alpha (IFN-alpha) stimulation. The constitutional expression of the L-selectins (LECAM-1), LFA-1/CD11a, VLA alpha-4/CDw49d and ICAM-1/CD54 adhesion molecules was detected, and changes in their density after IFN-alpha stimulation were compared to results obtained by the high endothelial venule (HEV)-binding assay and a carbohydrate (phosphonomannan core polysaccharide: PPME and fucoidin) immobilization test. The LECAM-1 and ICAM-1 molecules were expressed on the great majority of CLL cells, while the LFA-1 and VLA-4 alpha-chains were expressed by only a small number of cells. Statistically significant changes (p < 0.001) were observed in LECAM-1 antigen density (changes in mean cell fluorescence), as well as in functional tests (HEV-, PPME- and fucoidin-binding; p < 0.01) after in vitro IFN-alpha stimulation. Based on a prior study (Jewell et al., Leukemia 1992: 6: 400-404) and on the present findings, not only an increased expression but also an enhanced function of the L-selectins seem to be well substantiated after IFN-alpha stimulation, which may explain the therapeutic effect of IFN-alpha in reducing the accumulation of leukaemic B cells in the blood. The remarkably high expression of ICAM-1 in this series necessitates further studies to clarify the exact expression rate and role of this molecule.

Adult↗

Role of complement activation in hypersensitivity reactions to doxil and hynic PEG liposomes: experimental and clinical studies.

Pegylated liposomal doxorubicin (Doxil) and 99mTc-HYNIC PEG liposomes (HPL) were reported earlier to cause hypersensitivity reactions (HSRs) in a substantial percentage of patients treated i.v. with these formulations. Here we report that (1) Doxil, HPL, pegylated phosphatidylethanolamine (PEG-PE)-containing empty liposomes matched with Doxil and HPL in size and lipid composition, and phosphatidylglycerol (PG)-containing negatively charged vesicles were potent C activators in human serum in vitro, whereas small neutral liposomes caused no C activation. (2) Doxil and other size-matched PEG-PE and/or PG-containing liposomes also caused massive cardiopulmonary distress with anaphylactoid shock in pigs via C activation, whereas equivalent neutral liposomes caused no hemodynamic changes. (3) A clinical study showed more frequent and greater C activation in patients displaying HSR than in non-reactive patients. These data suggest that liposome-induced HSRs in susceptible individuals may be due to C activation, which, in turn, is due to the presence of negatively charged PEG-PE in these vesicles.

Animals↗

Expression and function of L-selectin molecules (LECAM-1) in B-cell chronic lymphocytic leukemia.

BACKGROUND: The notion that adhesion molecules play a crucial role in lymphoma/leukemia dissemination is widely accepted. Individual cases of B-cell chronic lymphocytic leukemia (B-CLL) show well-defined variables in the extent and pattern of peripheral blood and nodal involvement. The L-selectin adhesion molecule (TQ1/Leu-8, LAM series and LECAM-1) initiates the attachment of lymphocytes to the high endothelial venules (HEVs), and as a consequence the entrance of lymphocytes from the blood into the peripheral lymph node (recirculation which may be operative in lymphoma/leukemia dissemination as well). MATERIALS AND METHODS: The constitutional expression of L-selectin molecules (LECAM-1) on peripheral blood mononuclear cells (PBMCs) from B-CLL (16 cases) was examined and correlated with receptor function in an HEV-binding assay and in a ligand immobilization test. RESULTS AND CONCLUSIONS: A correlation was found between constitutional expression and function of the L-selectins, namely the higher the number of cells expressing L-selectin molecules at a measurable level on the cell surface, the greater the number of cells showing attachment in the tests. It is suggested that many aspects of the biological and clinical heterogeneity of B-CLL will be explained by revealing the exact adhesion profile and function in different subtypes of the disease.

Aged↗