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Biomedical subjects

S Slavin

Publications and source records attributed to S Slavin.

At least 235 records · Page 13Linked to original sources

Enhanced marrow recovery by short preincubation of marrow allografts with human recombinant interleukin-3 and granulocyte-macrophage colony-stimulating factor.

We studied an alternative method of using hematopoietic growth factors (HGFs) to enhance hematopoietic recovery in patients undergoing bone marrow transplantation (BMT), by short in vitro preincubation. Twenty consecutive patients with leukemia received T-cell-depleted allografts using Campath-1G. Two thirds of the marrow was infused on the scheduled day of transplant and one third of the marrow following preincubation with granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-3 (IL-3) on day 4. Engraftment parameters and duration of hospitalization were compared by actuarial analysis to those of 40 historical controls. Patients receiving the incubated boost had significantly faster platelet recovery (P = .017) and shorter hospitalization period (P = .001) when compared with the control subjects. Platelet count reached greater than 25 x 10(9)/L on day 17 (median) in the study group and on day 23 in the controls. The median duration of hospitalization was 20 and 36 days, respectively. In the early posttransplantation follow-up, two of four patients in the study group died as a result of graft rejection, while all 13 deaths in the control group resulted from complications associated with marrow suppression. We suggest that pretransplant in vitro activation of bone marrow cells with IL-3 and GM-CSF may prove to be an efficient method for enhancing marrow recovery after BMT.

Adult↗

Recombinant human granulocyte-macrophage colony-stimulating factor after high-dose chemotherapy and autologous bone marrow transplantation with unpurged and purged marrow in non-Hodgkin's lymphoma: a double-blind placebo-controlled trial.

The toxicity of autologous bone marrow transplantation (ABMT) is correlated to neutropenia. Although recombinant human granulocyte-macrophage colony-stimulating factor (rhu GM-CSF) seems to hold promise in accelerating neutrophil recovery, few analyses from randomized studies are presently available. Ninety-one patients with non-Hodgkin's lymphoma receiving high-dose ablative chemotherapy followed by ABMT with unpurged or purged marrow were included in a randomized, double-blind, placebo-controlled trial. Forty-four patients received 250 micrograms rhu GM-CSF (Escherichia coli)/m2 and 47 patients received placebo. Treatment was administered daily as continuous infusion from day of ABMT until the absolute neutrophil count (ANC) reached 0.5 x 10(9)/L for 7 days or until day 30, whichever was first. With rhu GM-CSF, 50% of the patients reached an ANC count greater than 0.5 x 10(9)/L at day 14 as opposed to day 21 with placebo (P less than .0001). Patients transplanted with marrow purged by mafosfamide also recovered earlier when treated with rhu GM-CSF (16 v 20.5 days, P = .013). The hospitalization duration was shorter in the rhu GM-CSF group (median, 23 v 28 days, P less than .05). No difference was observed in fever, number of infections, and antibiotic administration between the two groups. The major adverse event ascribed to rhu GM-CSF was a capillary leak syndrome in three patients graded as severe in two patients, moderate in one, and reversible in all three patients. In addition, one patient in the rhu GM-CSF group died suddenly with no explanation. In long term follow-up, the relapse rate was identical in both groups and there was no significant difference in the number of deaths at 1 year (12 with rhu GM-CSF v 9 with placebo), although deaths seemed to occur slightly earlier in the rhu GM-CSF group. We conclude that after ABMT with purged or unpurged marrow, rhu GM-CSF (E coli) significantly reduces neutropenia duration and hospitalization stay. A positive causative relation between the study drug and/or its mode of application with an increased toxicity as compared with GM-CSF from other sources and/or other modes of application cannot be deduced from the experiences in this study. Additional randomized trials would be necessary for an appropriate answer.

Adolescent↗

Antitumor effects of human recombinant interleukin-6 on acute myeloid leukemia in mice and in cell cultures.

Interleukin-6 (IL-6) has been shown to inhibit growth and induce differentiation of several myeloid leukemia cell lines. In this work, two in vivo models of acute myeloid leukemia (AML) in mice have been used to test the therapeutic potential of recombinant human IL-6. In mice inoculated by a transplantable AML tumor, IL-6 injections inhibited the development of leukemia and increased survival. The effect was related to dose and length of treatment. In a model of radiation-induced leukemogenesis in SJL/J mice, administration of low-dose IL-6 for 10 days, 4 months after irradiation, reduced the incidence of leukemia observed during 1 year, whereas granulocyte-macrophage colony-stimulating factor (GM-CSF) increased the incidence of leukemia. In vitro liquid cultures of leukemic blood cells obtained from AML patients showed that IL-6 slowed growth and decreased the proportion of blasts with an increase in more mature myeloid elements in 72% of M1, M2, M4 AML cases. In contrast, GM-CSF less often produced differentiation but stimulated leukemic cell growth in liquid cultures, without synergism by IL-6.

Animals↗

Prevention of experimental autoimmune encephalomyelitis and induction of tolerance with acute immunosuppression followed by syngeneic bone marrow transplantation.

Experimental autoimmune encephalomyelitis (EAE) is an inducible autoimmune disease widely used as a model of the acute/relapsing stage of multiple sclerosis. In the present study we examined the effect of acute immunosuppression induced by total body irradiation (TBI) (900 to 1100 centigray (cGy)) or by a single high dose of cyclophosphamide (CY) (300 mg/kg), followed by syngeneic bone marrow transplantation (SBMT), on the development of EAE in SJL/J mice. EAE was induced in SJL/J mice by immunization with spinal cord homogenate in adjuvant. Treatment with TBI (900 cGy) and SBMT on day 6 postimmunization caused a delayed onset and a marked reduction in the incidence and severity of EAE. A higher dose of irradiation (1100 cGy) or the administration of CY followed by SBMT completely abrogated the development of paralysis. None of the 21 mice treated with CY and SBMT, and only 1 of 7 mice treated with TBI (1100 cGy) and SBMT developed clinical signs of EAE during a period of 3 months. Furthermore, mice treated with CY and SBMT became resistant to rechallenge with the same encephalitogenic inoculum. In addition, the lymphocytes obtained from these mice did not proliferate in vitro in response to myelin basic protein or tuberculin-purified protein derivative, unlike lymphocytes from immunized but untreated animals. This absence of reactivity was not associated with alterations in the proportion of the L3T4 and Lyt-2 T-cell subsets nor with a loss in T cell competence as evidenced by the full response of lymphocytes to the T cell mitogen Con A and to a nonrelevant Ag (OVA). Our results indicate that the elimination of effector lymphocytes either by myeloablative doses of CY or ionizing irradiation followed by rescue with SBMT inhibits the development of the autoimmune process in EAE and leads to induction of tolerance to the immunizing Ag by newly developing lymphocytes. This approach of combining immunoablation and reconstitution with autologous bone marrow transplantation may be applicable in the treatment of life-threatening neurologic autoimmune diseases.

Animals↗

Superoxide dismutase inhibits radiation-induced lung injury in hamsters.

An animal model of pulmonary radiation-induced lung injury was established in the hamster and the effects of pretreatment with recombinant human CuZn superoxide dismutase (SOD) on the development of the lesion were evaluated. Hamsters exposed to a single irradiation dose of 2000 cGy delivered to the thorax were treated with 150 mg/kg body weight of SOD or an equivalent volume of saline intraperitoneally 75 min and subcutaneously 5 min before receiving irradiation. At 4, 8, and 16 weeks following irradiation, pulmonary injury was evaluated by the grading of morphologic changes semiquantitatively, measurement of lung hydroxyproline content, and analysis of bronchoalveolar lavage fluid for total and differential cell counts and total protein concentration. Radiation-induced lung injury in saline-pretreated animals was documented at 16 weeks by histologic morphology and increased protein in bronchoalveolar lavage fluid. SOD protected against radiation-induced pulmonary injury as indicated by the absence of severe histopathologic changes and prevention of elevation in bronchoalveolar lavage protein levels. The beneficial effects of SOD in preventing radiation-induced pulmonary toxicity suggests that this recombinant enzyme may play a role in protection against radiation-induced pulmonary injury in humans.

Animals↗

Immunological evaluation of patients with hematological malignancies receiving ambulatory cytokine-mediated immunotherapy with recombinant human interferon-alpha 2a and interleukin-2.

Immunological parameters were evaluated in patients treated with cytokine-mediated immunotherapy (CMI) consisting of low doses of recombinant human interferon alpha 2a (rIFN alpha) and recombinant human interleukin-2 (rIL-2) administered either concomitantly or sequentially by subcutaneous self-injections in an outpatient setting. Twenty-six patients with hematological malignancies and 2 metastatic melanoma patients in a progressive stage were enrolled in this clinical trial. Of the 26 patients, 24 were at a stage of minimal residual disease, including 14 patients who had received autologous bone marrow transplantation (ABMT) 2-5 months previously, 7 chronic myelogenous leukemia (CML) and 3 acute myeloid leukemia (AML) patients. Two patients (1 CML and 1 mult. myeloma) were treated at a stage of progressive disease. Non-MHC-restricted cytotoxicity directed against natural-killer(NK)-resistant (Daudi) and NK-sensitive (K562) target cells was assessed before, during and after CMI, either in fresh peripheral blood samples (spontaneous activity) or after in vitro rIL-2 activation (induced activity). Spontaneous killing activity was low prior to treatment, but increased upon termination of treatment in 10/15 evaluated cycels. rIL-2-activated cytotoxicity in vitro was markedly elevated in 8/12 and 6/8 patients after one and two cycles, respectively, of sequential treatment, as well as in 3/8 CML and 5/6 patients after one and two cycles, respectively, of concomitant treatment. Activation of the T cell mitogenic response was demonstrated in 6/9 patients after concomitant CMI, while no such effect was observed throughout a sequential treatment in lymphoma and leukemia patients after ABMT. Although a direct correlation between immune stimulation and the in vivo antitumor response cannot yet be determined, our clinical observations support a beneficial therapeutic effect in a substantial number of patients. These results indicated that the ambulatory CMI protocol of rIL-2 and rIFN alpha could stimulate the host defense immune system and may be helpful in mediating the in vivo antitumor response in patients with minimal residual disease.

Adolescent↗

Effects of interleukin 2 on engraftment following autologous bone marrow transplantation (ABMT) in dogs.

Beagle dogs were treated with recombinant human interleukin 2 (IL-2) 6 x 10(6) International Units (IU)/day for 7 consecutive days following conditioning with sublethal (200 cGy) or lethal (400 cGy) doses of high-dose rate whole body irradiation (WBI) and reconstitution with 2 x 10(8)/kg autologous bone marrow cells, in order to assess the effect of IL-2 on engraftment. Engraftment of dogs conditioned by lethal doses of WBI was not impaired following treatment with IL-2 6 x 10(6) IU/day. At an RIL-2 dose of 6 x 10(6) and 9 x 10(4) IU/day, enhanced engraftment of autologous bone marrow cells was observed in dogs irradiated with a sublethal WBI dose in comparison with controls not treated by IL-2(p < 0.05). We conclude that therapeutic doses of IL-2 may be safely utilized during hematopoietic reconstitution. Under certain conditions IL-2 may even enhance hematopoietic reconstitution following ABMT.

Animals↗

Chronic-relapsing experimental autoimmune encephalomyelitis (CR-EAE): treatment and induction of tolerance, with high dose cyclophosphamide followed by syngeneic bone marrow transplantation.

We examined the effect of acute immunosuppression with high dose cyclophosphamide (CY), followed by syngeneic T-cell-depleted bone marrow transplantation (SBMT) on chronic-relapsing autoimmune encephalomyelitis (CR-EAE) induced in SJL/J mice by immunization with mouse spinal cord homogenate (MSCH) in adjuvant. Treatment of mice on day 9 post immunization, before the appearance of clinical signs of the disease, delayed the onset of paralysis, but did not affect its clinical course. Treatment on day 2-3 after the first clinical signs led to complete regression of the disease. During a period of 3 months, only one of the 15 mice treated after the the onset of CR-EAE relapsed, as compared to a total of 21 relapses in the 15 untreated animals. A rechallenge with MSCH in adjuvant on day 78 after immunization induced a severe relapse in all untreated mice, with 78% mortality; in contrast, only 25% of mice treated with CY and SBMT relapsed when similarly rechallenged. Lymphocytes from mice treated with CY and SBMT showed reduced in vitro proliferative responses to myelin basic protein (GMBP) and PPD, even after the rechallenge with MSCH. Our results show that high dose CY for elimination of immunocompetent lymphocytes, followed by SBMT rescue, suppresses CR-EAE and induces tolerance to the immunizing antigens. These results may encourage attempts to apply a similar therapeutic principle in life-threatening human neurological autoimmune diseases.

Animals↗

Immunotherapy of minimal residual disease by immunocompetent lymphocytes and their activation by cytokines.

A murine model of minimal residual disease (MRD) was established utilizing the murine B-cell leukemia (BCL1). BALB/c mice inoculated with up to 10(4) BCL1 were cured (greater than 1 year disease-free survival) following administration of intraperitoneal injections of recombinant human IL-2 (10(5) Cetus units x 3/day intraperitoneally x 5 days). Lethally irradiated BALB/c or (BALB/c x C57BL/6)F1 recipients were reconstituted with syngeneic bone marrow cells or T-cell-depleted C57BL/6 bone marrow cells contaminated with 10(4), 10(5), or 10(6) BCL1 to simulate quantitative MRD. Untreated mice died of typical leukemia without exception, whereas a substantial anti-leukemia effect was noted in mice treated by allogeneic spleen cells, IL-2, or particularly a combination of allogeneic spleen cells and IL-2 given concomitantly. Increments of donor-type spleen cells (10(6), 10(7), and 5 x 10(7)) or IL-2 (10(4) U x 2/day x 3 days) were given alone or in combination on days +1, +5, and +9 following Thy 1.2-depleted allogeneic BMT. All adoptive recipients of 10(5) spleen cells obtained from mice inoculated with 10(4) and 10(5) BCL1 treated by a combination of allogeneic spleen cells and IL-2 showed no evidence of disease greater than 100 days. The antitumor effects of allogeneic spleen cells alone and IL-2 alone were also highly significant, although not totally curative in all mice. Allogeneic spleen cells seemed more effective as compared with low dose IL-2 (3 courses of 2 x 10(4) U x 2/day x 3 days). None of the recipients of 10(6) BCL1 could be completely cured under the experimental conditions described without additional chemotherapy, although significant antitumor effects could again be documented following concomitant administration of allogeneic spleen cells and IL-2. Using an experimental model of autologous BMT, recipients of 10(3) tumor cells could also be cured following transplantation of syngeneic spleen cells by high-dose IL-2 (10(5) U x 3/day x 5 days) given at the time lymphocytes were present, optimally at 3 weeks following BMT. Based on encouraging results from experiments using our animal model of MRD, in conjunction with autologous and allogeneic BMT, pilot clinical trials are currently underway, investigating the effect of cytokine-mediated immunotherapy (CMI) in MRD following conventional and high-dose cytoreductive anticancer therapy in conjunction with ABMT. In addition, we are attempting induction of cell-mediated cytokine-activated immunotherapy (CCI) in conjunction with autologous and allogeneic BMT. Prospective randomized clinical trials and longer observation periods are required to assess the full efficacy of these new therapeutic modalities.

Animals↗

Use of recombinant human interleukin-2 in conjunction with bone marrow transplantation as a model for control of minimal residual disease in malignant hematological disorders: I. Treatment of murine leukemia in conjunction with allogeneic bone marrow transplantation and IL-2-activated cell-mediated immunotherapy.

Immunotherapy with recombinant human interleukin-2 (IL-2) and allogeneic spleen cells has led to significant antitumor effects in B-cell leukemia- (BCL1) bearing mice following transplantation with T-lymphocyte-depleted allogeneic bone marrow cells. Graft versus leukemia (GVL) effects were studied in a model mimicking minimal residual disease following bone marrow transplantation (BMT). Lethally irradiated (BALB/c x C57BL/6)F1 recipients were reconstituted with 20 x 10(6) T-lymphocyte-depleted C57BL/6 bone marrow cells mixed with 10(4) to 10(6) BCL1 cells followed by administration of sequential increments of allogeneic C57BL/6 spleen cells; 10(6) cells on Day +1, 10(7) cells on Day +5, and 5 x 10(7) cells on Day +9, with or without concomitant IL-2 treatment (intraperitoneal injections of 20,000 U twice daily for 3 days) together with each spleen cell administration. All mice receiving 10(4)-10(6) BCL1 cells developed marked splenomegaly by Day +21 and all adoptive recipients of 10(5) spleen cells obtained from these mice developed leukemia within 21-36 days. Treatment of mice which received 10(4) BCL1 cells by either three courses of low dose IL-2 or three increments of allogeneic spleen cells alone and certainly by a combination of both resulted in normalization of splenomegaly on Day +21, but only adoptive recipients of 10(5) spleen cells obtained from mice treated by both allogeneic spleen cells and IL-2 (10/10) or allogeneic spleen cells alone (8/10) were disease free (greater than 100 days). Mice inoculated with 10(5) BCL1 cells developed mild splenomegaly on Day +21 after IL2 treatment alone, but showed no clinical evidence of disease following administration of allogeneic spleen cells or both allogeneic spleen cells and IL-2. Following adoptive transfer of 10(5) spleen cells obtained from each treated group no leukemia (greater than 100 days) was evident in recipients of spleen cells obtained from mice treated with both allogeneic spleen cells and IL-2 (10/10) whereas a partial effect was observed in mice treated by allogeneic spleen cells only (4/10). Mice inoculated with a high dose of BCL1 cells (10(6] showed some delay in onset of splenomegaly, but no curative antileukemic effects could be observed even following a synergistic combination of IL-2 and allogeneic spleen cells. Our data suggest that immunocompetent allogeneic lymphocytes may play an important role against leukemic relapse and thus cell therapy may be used therapeutically to treat minimal residual disease after BMT even following initial reconstitution with T-cell-depleted bone marrow cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

Successful T cell-depleted allogeneic bone marrow transplantation in a child with recurrent multiple extramedullary plasmacytomas.

Multiple plasmacytomas with IgA paraproteinemia, a low grade lymphoid neoplasm of differentiated B cells rarely seen in the young, were encountered in a 10-year-old child. T cell-depleted allogeneic bone marrow transplantation (BMT) was performed because of progressive disease despite chemotherapy. Donor T cells were infused after transplantation in gradually increasing numbers to achieve a graft-versus-tumor effect. Complete eradication of all tumor masses was achieved following BMT with normalization of serum immunoglobulin levels. The patient remains in complete remission 4 years after BMT. Allogeneic BMT should be considered early in the course of low-grade lymphoid malignancy in the younger age group.

Bone Marrow Transplantation↗

Immunotherapy of minimal residual disease in conjunction with autologous and allogeneic bone marrow transplantation (BMT).

Recent investigations in animal models of human lymphoid and myeloid leukemia suggest that induction of immune-mediated antitumor effects is feasible at the stage of minimal residual disease (MRD) using allogeneic immunocompetent lymphocytes following initial reconstitution with T cell depletion and/or activation of reconstituting syngeneic or allogeneic immune cells by recombinant interleukin-2 (rIL2). Pilot clinical trials in patients with leukemias and lymphomas at high risk to relapse following autologous bone marrow transplantation (BMT) suggest that beneficial antitumor effects may be achieved at the stage of MRD by home immunotherapy as soon as hematopoietic reconstitution occurs using rIL2 (Cetus) and alpha interferon (Roferon A) (Hoffmann LaRoche). Although results obtained from our open trial seem encouraging, prospective randomized trials and longer observation periods are needed in order to confirm immune-mediated antitumor effects in conjunction with autologous BMT in patients with malignant hematological disorders at high risk to relapse. Likewise, it seems that amplification of anti-leukemia effects following allogeneic BMT is feasible by post-transplant infusion of donor's peripheral blood lymphocytes for prevention and/or treatment of relapse.

Adolescent↗

Radiosensitivity and responsiveness to recombinant interleukin-2 of effector cells of graft vs. host disease and mixed lymphocyte reaction in mice.

Synergistic effects of recombinant interleukin-2 (IL-2) or irradiated spleen cells were investigated in vivo and in vitro. Irradiated (750 cGy) C57BL/6 spleen cells infused to sublethally irradiated (500 cGy) BALB/c mice treated with IL-2 (1,000 U 3 times/day) caused graft vs. host-like disease (GVHD) in 3 of 11 mice. Similarly irradiated allogenic spleen cells caused no GVHD in irradiated recipients not administered IL-2. No sign of autologous GVHD was found in mice that received irradiated syngeneic spleen cells with IL-2. Addition of recombinant IL-2 in vitro to mixed lymphocyte reactions (MLR) using irradiated (500 cGy) allogeneic responder spleen cells augmented the 3H-TdR uptake fourfold compared to cultures without IL-2, but was 44-fold below the allogeneic response of nonirradiated C57BL/6 spleen cells. Il-2-induced cell proliferation was also noted in syngeneic MLR, but did not lead to GVHD in in vivo experiments. The data suggest that IL-2 may potentiate GVHD and alloreactivity induced by an adequate number of irradiated, nondividing but viable allogeneic spleen cells and/or that secretion of IL-2 by alloactivated T lymphocytes, supplied exogenously in the present study, may play a role in the GVHD syndrome. Since neither viable but nonreplicating T cells nor IL-2 alone caused GVHD, it is suggested that endogenously produced IL-2 by alloactivated T lymphocytes may be important in the development of the GVHD syndrome, independent of its main function of enhancing T lymphocyte proliferation. On the other hand, the lack of GVHD following administration of high numbers of irradiated or nonirradiated syngeneic spleen cells with IL-2 implies that allogeneic T lymphocytes and not IL-2 activated MHC-nonrestricted cytotoxic cells play a role in inducing the GVHD syndrome in vivo.

Animals↗

Clinical application of intrauterine bone marrow transplantation for treatment of genetic diseases--feasibility studies.

Intrauterine bone marrow transplantation (BMT) may represent a new approach for correction of a large variety of genetic disorders in utero. The procedure may become feasible for more genetic disorders in the future, since a large majority of potentially correctible diseases can be diagnosed at an early stage of gestation in utero using molecular probes that permit analysis of small biologic samples and even few cells that may be obtained by chorionic villi biopsy and/or amniocentesis. Haploidentical paternal marrow (2 cases) and sibling bone marrow cells from a disease-free family members, were infused into the fetus. GVHD was avoided following in vitro T-lymphocyte depletion using monoclonal antilymphocyte (CDW52) antibodies (Campath-1) without affecting stem cell viability, similarly to the procedures in routine use in clinical BMT programs in man. Three women underwent intrauterine BMT at 34, 23 and 25 weeks of gestation for metachromatic leucodystrophy (Arylsulfatase A deficiency, 2 cases) and beta thalassemia major (1 case), respectively. A total of 33 x 10(8), 30 x 10(8) and 30 x 10(8) bone marrow cells were infused intraperitoneally (1 case), intraportally plus intraperitoneally (2 cases) with no fetal distress. Although the procedure was uneventful and no clinical evidence of GVHD was observed following delivery, correction of the basic disorders was not accomplished because of anticipated rejection of marrow allografts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Typhlitis occurring in autologous bone marrow transplantation.

A case of typhlitis which complicated the course of autologous bone marrow transplantation (ABMT) is reported. It is the first report of such a life-threatening complication in the setting of ABMT. Conservative treatment without surgical intervention may offer the best results.

Acinetobacter Infections↗