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S Slavin

Publications and source records attributed to S Slavin.

At least 73 records · Page 4Linked to original sources
PubMed1988

Bone marrow transplantation in beta-thalassemia major. The Israeli experience.

The present report summarizes our experience in applying a new approach in bone marrow transplantation for the treatment of beta-thalassemia major. Ex-vivo pretransplant T-lymphocyte depletion with CAMPATH-1 was used for prevention of acute and chronic graft versus host disease and total lymphoid irradiation was added for the conditioning regimen for abrogation of potential rejection of T-cell depleted marrow allografts. Ten patients with homozygous beta-thalassemia major were 9-48 months of age (median 18.5 months) and received HLA-identical allogeneic T-cell depleted marrow after treatment with total lymphoid irradiation, busulfan and cyclophosphamide. Seven patients are alive and free of disease, 3-46 months post-transplantation. The actuarial probability of survival and of disease-free survival at two years was 70%. Three patients died: one of intracranial hemorrhage post-transplantation, one from busulfan interstitial pneumonitis, and one who rejected the first graft and developed fatal chronic graft versus host disease after a second transplant. Seven patients are alive and well with follow-up of 3-45 months, with no signs of acute or chronic GVHD. We conclude that T-cell depleted bone marrow transplantation is indicated for homozygous transfusion dependent young patients with beta-thalassemia who are minimally transfused, particularly in areas where optimal conventional therapy is not feasible.

Bone Marrow Transplantation↗
PubMed1988

Interstitial pneumonitis in T cell-depleted bone marrow transplantation.

The incidence of interstitial pneumonitis (IP) was reviewed in 80 consecutive patients who received allogeneic T lymphocyte-depleted bone marrow transplantation (BMT) for malignant and non-malignant diseases. Pretransplant conditioning used in malignant disorders included total lymphoid irradiation (TLI) 150 cGy x 4, total body irradiation (TBI) 200 cGy x 6, and cyclophosphamide (CY) 120 mg/kg. In non-malignant diseases conditioning included no TBI, but adjusted doses of TLI in addition to CY (severe aplastic anemia) or CY and busulfan (severe beta-thalassemia major). In the malignant group only one patient developed graft-versus-host disease (GVHD) grade I; IP developed in 12 out of 61 patients (19.7%) and IP-associated fatality occurred in five patients (8.2%). Cytomegalovirus (CMV) was associated with only two of the five fatal IP. In the non-malignant group there was no GVHD; one patient out of 19 (5.2%) had IP, which was fatal and not associated with CMV. These data indicate that fatal IP may appear in the absence of GVHD. The relatively low incidence of IP-related mortality in recipients of allogeneic T lymphocyte-depleted BMT suggests that although prevention of GVHD and elimination of drugs used for GVHD prevention may reduce the incidence of fatal pulmonary complications, other approaches have to be investigated for complete prevention of IP which still represents a major complication in patients with malignant hematologic disorders treated by allogeneic BMT.

Adult↗
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↗
PubMed1988

Preliminary characterization of functional residual host-type T lymphocytes following conditioning for allogeneic HLA-matched bone marrow transplantation (BMT).

Host T lymphocytes which escape the effects of chemoradiotherapy may proliferate and lead to graft rejection, particularly in recipients of T cell-depleted bone marrow (BM) allografts. We studied the efficacy of several conditioning regimens including a new immunosuppressive regimen--total lymphoid irradiation (TLI) plus conventional chemotherapy and total body irradiation (TBI)--in abrogating residual host T lymphocytes as assessed by their ability to grow in vitro. A total of 38 patients were evaluated, 29 with hematologic malignancies, six with severe aplastic anemia (AA) and three with beta-thalassemia major (TM), of whom 32 were transplanted with HLA-identical T cell-depleted allogeneic BM from sibling donors. The median observation period was 15 months (range 3-21) posttransplant. Peripheral blood mononuclear cells (PBMC) taken from each patient on the day of transplant were cultured with interleukin 2 (IL-2) + phytohemagglutinin + irradiated donors' PBMC. Survival of cells for less than 2 weeks in vitro without proliferation was observed in 20 of 29 cases with malignancies and was considered negative. In this group only two leukemia (L) patients rejected the graft. Limited cell growth (less than or equal to 3 weeks) was seen in four L patients, two of whom showed early graft failure. Vigorous T cell growth (greater than 5 weeks, 62-96% CD4+ cells) was noted in eight cases (two L, four AA, two TM; none received TBI). In this group, sustained engraftment was observed in 7/7 patients who were treated with cyclosporin A (CSA) post grafting. Overall, we could demonstrate no clear correlation between graft failure and cell growth in vitro. The proliferating cells exhibited considerable cytotoxic activity in vitro against several tumor cell lines and were susceptible to pharmacological doses of CSA. The low incidence of continuous T cell proliferation in vitro in PBMC of L patients suggests that a combination of TLI, TBI and cyclophosphamide (CY) is highly effective in abrogating the host T cells and subsequent graft rejection. Since a rather small number of patients was included in this study, further studies are needed to determine the possible value of the in vitro T cell proliferation assay as a means for predicting graft failure.

Adolescent↗
PubMed1988

Optimal time interval between myeloablative whole body irradiation and reconstitution with syngeneic bone marrow graft.

The optimal time interval between termination of radiation therapy and marrow grafting has been studied in an animal model of syngeneic bone marrow transplantation, using a limiting number of bone marrow cells. Optimal survival was achieved when reconstitution took place 24 h following termination of radiation therapy at all cell doses studied, including 5 x 10(4), 2 x 10(5) and 1 x 10(6) cells/recipient. The worst results were observed when bone marrow cells were infused immediately after irradiation. These results suggest that reconstitution of lethally irradiated recipients requires migration of irradiated host marrow cells and establishment of adequate 'bone marrow space', which is optimal at 24 h following termination of whole body irradiation.

Animals↗
PubMed1988

In vitro and in vivo cytokine-induced facilitation of immunohematopoietic reconstitution in mice undergoing bone marrow transplantation.

The aim of this study was to test whether colony stimulating factors (CSF) and other cytokines facilitate the recovery of a variety of immunohematopoietic functions in lethally irradiated mice undergoing bone marrow transplantation (BMT). Two experimental systems were employed: (a) lethally irradiated mice transplanted with syngeneic or T cell-depleted semi-allogeneic bone marrow (BM) cells (0.1-10 x 10(6)), subsequently treated by multiple doses of cytokines; and (b) lethally irradiated mice transplanted with BM cells that had previously been cultivated with cytokines. The cytokines used were: pure natural mouse interleukin-3 (IL-3); recombinant mouse granulocyte-macrophage CSF (rGM-CSF); recombinant human interleukin-2 (rIL-2); and crude cytokine preparations obtained from the culture supernatants of murine leukemia WEHI-3b cells (containing mainly IL-3), and of phorbol myristate acetate (PMA)-stimulated EL4 leukemia cells and concanavalin A-stimulated rat splenocytes (each containing a multitude of cytokines). For BM cultures (1-9 days), the cytokines were used at a dosage of 1-100 U/ml; for in vivo treatment, 2 x 10(2)-5 x 10(4) units were administered intraperitoneally and subcutaneously at different schedules for varying periods (1-3 weeks). The following parameters were tested 1-10 weeks post-BMT: white blood cell count, colony formation in agar and in the spleen of lethally irradiated mice, proliferative responses to mitogens and alloantigens, allocytotoxicity and antibody production (serum agglutinins and plaque-forming cells) against sheep red blood cells. Under appropriate conditions, cytokine treatment either in vitro or in vivo significantly enhanced (2- to 50-fold compared with controls) most functions tested at 2-8 weeks post-BMT, and shortened the time interval required for full immunohematopoietic recovery by 2-5 weeks. In recipients of semi-allogeneic, T lymphocyte-depleted BM no evidence of graft-versus-host disease was found. It is suggested that judicious application in vitro and/or in vivo of certain pure cytokines (e.g. GM-CSF, IL-3) or cytokine 'cocktails' might be beneficial in enhancing hematopoiesis and in the treatment of immunodeficiency associated with BMT.

Animals↗
PubMed1988

Prevention of herpes simplex virus (HSV) infection in recipients of HLA-matched T-lymphocyte-depleted bone marrow allografts.

The occurrence of HSV infection and the effect of prophylaxis with oral acyclovir were evaluated prospectively in 34 consecutive patients undergoing bone marrow transplantation (BMT). All allogeneic BMT procedures involved T-lymphocyte depletion for prevention of graft-vs.-host disease (GVHD). Five HSV-seronegative patients did not receive acyclovir, and they did not develop HSV infection. Oral acyclovir was administered to 15 HSV-seropositive BMT recipients; 14 untreated HSV-seropositive BMT recipients served as a control group. The adult dose of acyclovir was 400 mg three times a day on Days -6 to +14 and 200 mg three times a day on Days +15 to +90. Children received 500 mg/m2 per day divided into three equal doses on Days -6 to +14 and 250 mg/m2 per day again divided into three on Days +15 to +90. In the group on prophylaxis, only one developed HSV infection during the time prior to engraftment. In the reference group, 12 of 14 (85.7%) developed oral HSV infection within 0 to 16 days (median 11 days) after the transplantation. Time for engraftment (duration of neutropenia) was shorter in patients receiving acyclovir. After engraftment, HSV infection was not observed during administration or following discontinuation of acyclovir on Day 90, but occurred in three patients in whom acyclovir was discontinued on Days 25, 35 and 40 after BMT. In the untreated group, two patients had recurrence of HSV infection on Days 40 to 60, and one had two infectious episodes. GVHD occurred in only two recipients, neither of whom had HSV infection. We conclude that the incidence of HSV infection during the period until engraftment in recipients of T-lymphocyte-depleted BMT is high, similar to that reported by others in recipients of whole BMT. Relatively low-dose oral acyclovir administered for 90 days can effectively prevent HSV infections in previously HSV-seropositive BMT recipients and may also shorten the period until engraftment.

Acyclovir↗
PubMed1987

Alloantigen persistence in induction and maintenance of transplantation tolerance.

Infusion of parental bone marrow cells into F1 hybrids conditioned by total lymphoid irradiation (TLI) results in chimeras with a high percentage of donor-type cells, and without clinical signs of graft-vs.-host reaction. In these chimeras, a state of tolerance has been shown to be associated with paucity of cytotoxic T lymphocyte percursors (pCTL) reactive with host-type alloantigens. To determine whether the presence of tolerizing alloantigens is essential for maintenance of unresponsiveness, lymphohematopoietic cells obtained from such tolerant chimeras were transferred into supralethally irradiated recipients of two different genotypes: in one case the adoptive recipients were syngeneic with host-type cells, and in the other they were syngeneic with donor-type cells of the original chimeras, thus providing the chimeric cells with a tolerogen-free environment. After "parking" for 4 d in syngeneic donor-type mice, the transferred cells displayed a marked increase in the frequency of pCTL directed against tolerizing alloantigens, whereas a low pCTL frequency directed against the same H-2 target cells was maintained in allogeneic tolerizing-type adoptive recipients. Multiple injections of adoptive donor-type mice with tolerizing-type cells of the original chimera reestablished a low level of cytotoxic precursors. Cytotoxic activity against unrelated alloantigens was independent of the presence of tolerogen-presenting cells in the adoptively transferred mice. Our experimental model suggests that persistence of cells bearing tolerizing alloantigens is an essential requirement for maintenance of previously established tolerance.

Animals↗
PubMed1987

Suppressor T cells in allogeneic bone marrow chimeras.

Immunosuppression is believed to play a role in the maintenance of stable bone marrow (BM) chimeras. This study investigates the nature and specificity of the suppression that lymphocytes from allogeneic BM chimeras exert upon the alloreactivity of donor and recipient lymphocytes. Lethally irradiated CBA/J (H-2k) mice were infused with 10(7) unseparated (WBM) or T cell-depleted BM (TDBM) cells of B10.BR mice (H-2k, disparate at minor histocompatibility antigens). Mixtures consisting of spleen cells (SC) from BM chimeras and SC from either normal donor, recipient, or third party (C3H, H-2k) mice, were sensitized with irradiated BALB/c (H-2d) leukocytes, then assayed for proliferative and anti-H-2d cytotoxic activity and compared with those of appropriate control cultures. The alloreactivity of all three types of normal SC was non-specifically suppressed by SC from both WBM and TDBM chimeras taken 2 weeks post-BM transplantation (BMT). In contrast, at 4 weeks post-BMT, SC from both chimeras suppressed the alloreactivity of recipient-type cells whereas only SC from WBM, but not from TDBM chimeras, suppressed normal donor-type response, and neither could suppress the response of normal third party cells. The suppression of donor-type alloreactivity diminished with time, while that exerted on recipient-type lasted for at least 10 weeks post-BMT. The suppression of donor alloreactivity was mediated by radioresistant Thy1.2+, Lyt1+2+ cells while that exerted upon recipient's alloreactivity was mediated by radiosensitive Thy1.2+, Lyt1+2- cells. Both types of suppressor cells were of donor origin. The potential biological role of the suppressive activity in the engraftment of allogeneic BM is discussed.

Animals↗
PubMed1987

Bone marrow transplantation with T-cell-depleted grafts. II. Reconstitution of immunohemopoietic functions in lethally irradiated mice transplanted with unseparated or T-cell-depleted bone marrow grafts disparate at minor histocompatibility antigens.

Graft-versus-host disease (GVHD), a serious complication of allogeneic bone marrow transplantation (BMT), can be prevented by in vitro depletion of T cells from the bone marrow (BM) prior to transplantation. The purpose of this study was to assess the role of BMT cells in the reconstitution of various immune functions following BMT across minor histocompatibility barriers. Lethally irradiated CBA/J (H-2k) mice were grafted with either 10(7) unseparated or T-cell-depleted BM cells from B10.BR (H-2k, minor-histoincompatible) mice. Blood counts, BM colonies in agar, and various immune functions of spleen cells from the recipient mice were tested 2-12 weeks post-BMT and compared with those of normal donors. The following observations were made: (A) Peripheral blood lymphocyte counts decreased to 30% of normal 2 weeks post-BMT with almost normal recovery at 8 weeks. (B) The percentage of Thy1.2+ splenocytes reached normal levels at 8 weeks post-BMT. (C) The number of BM colonies (GM-CFU) was reduced to 10% at 2 weeks and fully recovered at 12 weeks. (D) Proliferative response to the B-cell mitogen LPS was fully reconstituted after 4 weeks; however, anti-SRBC PFC (following Mishell-Dutton cultures) was restored 50% at 8-12 weeks. (E) Reconstitution of T cell functions including proliferative responses to concanavalin A, phytohemagglutinin, and allogeneic leukocytes, and allocytotoxicity, did not exceed 50% even 12 weeks post-BMT. Overall, depletion of T cells from donor BM allografts incompatible at minor histocompatibility loci, did not seem to significantly alter the rate of immunohematopoietic reconstitution in the lethally irradiated BM recipients.

Animals↗
PubMed1987

Purging breast cancer cells in preparation for autologous bone marrow transplantation.

Mixtures of the T-47D human breast cancer cell line and normal human bone marrow cells were used for studying a new approach for purging epithelial tumor cells for autologous bone marrow transplantation (BMT) in breast cancer. Breast cancer cell line T-47D cells were shown to bind soybean agglutinin (SBA) in a specific fashion that could be blocked by D-galactose. Tumor cells were effectively purged by both SBA agglutination and depletion of cells bound to magnetic beads (0.7-5.0 micron) covalently linked to SBA. A depletion of 3-4 orders of magnitude of tumor cells was consistently accomplished by combining one step of agglutination followed by one cycle of SBA-magnetic bead depletion. Neither procedure affects stem cell recovery. We suggest that effective purging of breast cancer cells can be accomplished using SBA for autologous BMT in patients with advanced breast cancer.

Agglutination↗
PubMed1987

The effect of T lymphocyte depletion on susceptibility to influenza virus infection and development of anti-viral immunity in lethally irradiated mice reconstituted with syngeneic bone marrow grafts.

Lethally irradiated Balb/c mice reconstituted with syngeneic T cell-depleted or syngeneic untreated bone marrow (BM) were able to produce equal levels of hemagglutination inhibition (HI) antibodies at 4 weeks after bone marrow transplantation (BMT) in response to nasal infection with A/PR8 influenza virus given 1 week after BMT. Likewise, no differences in mortality rates could be observed following influenza virus infection 1 day after BMT. Antibody production was detected in 10-20% of BMT recipients. All animals responded to a secondary infection given 2 months later by production of secondary IgG-type HI antibodies. Mice reconstituted with BM enriched with spleen cells obtained from immune donors showed an improved survival rate as compared with recipients of naïve BM, immune BM or T-depleted BM obtained from immune mice. Our results indicate that T cell depletion by itself does not increase susceptibility of syngeneic BMT recipients to virus infection. However, immune spleen cells may play a significant role in conveying protection against influenza virus infections. Although recipients of both immune and naïve intact BM may mount better anti-influenza titers as compared with T-lymphocyte-depleted BMT recipients, it appears that the proportion of immune donor T cells in the marrow inoculum is insufficient for protection against influenza virus infection. Generation of memory cells to influenza viral antigens in the post-BMT period is not impaired in recipients of T-depleted marrow grafts, suggesting that memory cell precursors are unaffected by the T cell depletion procedure, or else that they were regenerated during the immediate post-BMT period from Thy 1.2-negative precursors.

Animals↗