Biomedical subjects
Publications and source records attributed to S Slavin.
Revising an unsatisfactory result after breast augmentation requires a thorough understanding of the cause of the abnormality to develop a rational and effective treatment plan to achieve the best possible result. Often, more than one manipulation is required to correct the deformity. Using the techniques presented here, successful revision can be performed in the vast majority of cases.
We have investigated the efficacy of graft-versus-leukemia (GVL) effects induced by cells obtained from different syngeneic and allogeneic lymphoid compartments, by comparing the response to cell therapy with syngeneic (BALB/c x C57BL/6)F1 (H-2d/b) (F1) or allogeneic C57BL/6 (H-2b) (B6) lymphocytes in F1 recipients inoculated with B-cell leukemia (BCL1) of BALB/c (H-2d) origin. Eradication of BCL1 was confirmed in vivo by adoptive transfer of 10(5) spleen cells obtained from treated mice into syngeneic BALB/c recipients. Immunotherapy induced by allogeneic but not syngeneic spleen and lymph node lymphocytes was therapeutically more effective than thymocytes and bone marrow cells (BMC). Alloreactive cells could be further activated in vivo with recombinant human interleukin-2 (rIL-2). The GVL effect of allogeneic lymphocytes was cell-dose-dependent; a heavy leukemia load was more efficiently eradicated after three doses than after a single dose of allogeneic spleen cells (100% versus 23% disease-free survival rate of secondary adoptive recipients respectively). The GVL effect induced by allogeneic spleen cells was preserved after ex vivo exposure of cells to 250 cGy, but not 500 cGy or more. Interestingly, GVL was preserved following administration of ex vivo irradiated (500 cGy) spleen cells when rIL-2 was administered in vivo (p < 0.05). Syngeneic effector cells did not induce GVL, regardless of in vitro and in vivo activation with rIL-2. Our data suggest that allogeneic but not syngeneic (in analogy to autologous) cell therapy may be an effective tool to control residual leukemia following high-dose chemo-radiotherapy. The feasibility of augmenting GVL by successive doses of activated allogeneic donor lymphocytes, partly inactivated in vitro by low-dose ionizing irradiation to prevent severe graft-versus-host disease (GVHD), may lead to safer therapeutic approaches that can be used to reduce the incidence of relapse while avoiding the risk of uncontrolled GVHD.
Graft-versus-leukemia (GVL) effects play a key role in the elimination of residual leukemia cells in the course of allogeneic bone marrow transplantation (alloBMT). GVL effects can also be induced by donor lymphocyte infusion following alloBMT. We have investigated the role of CD4+ and CD8+ T cells in the development of GVL in mice with B-cell leukemia/lymphoma (BCL1) following allogeneic cell therapy. Sublethally irradiated (C57BL/6 x BALB/c)F1 mice were intravenously inoculated with 10(5) BCL1 cells and given untreated or recombinant human Interleukin-2 (rIL-2)-activated C57BL/6 spleen cells. Effective elimination of clonogenic BCL1 cells was confirmed by adoptive transfer of spleen cells obtained from treated mice into secondary BALB/c recipients. GVL effects were maintained after inactivation of CD4+ cells with monoclonal anti-CD4 antibodies in the inoculum, while inactivation of CD8+ cells with monoclonal anti-CD8 antibodies resulted in complete loss of GVL effects induced both by resting and rIL-2-activated allogeneic spleen lymphocytes. These results indicate that Thy-1 cells play the major role in the induction of GVL effects, mediated by C57BL/6 effector T cells in this model. Since the number of natural killer (NK) cells also increased during in vitro culture with rIL-2, their contribution, especially that of CD8+ NK cells, in GVL effects mediated by rIL-2-activated CD8+ cells cannot be ruled out.
OBJECTIVE: To study the attitudes of entering first year (Y1) and graduating third year (Y3) primary care physician trainees from 3 different training program sites (a university hospital system site [UHS], a large staff-model health maintenance organization managed care system site [MCS], and a large public hospital system site [PHS]) toward selected aspects of managed care. DESIGN: A self-administered questionnaire was used in a cross-sectional study. PARTICIPANTS AND OUTCOME MEASURES: Participants were all Y1 and Y3 primary care trainees in internal medicine, pediatrics, and family medicine programs from 3 training program sites. Survey questions dealt with attitudes toward health services, managed care cost containment, and the role of the physician in society. RESULTS: Of eligible primary care trainees (n = 218), 91% completed the instrument. Trainees at the MCS generally held more positive views of managed care systems than trainees at the UHS or PHS. Internal medicine trainees held more negative attitudes towards managed care systems than trainees in pediatrics or family medicine. UHS and PHS trainees more often thought that managed care systems interfere with the doctor-patient relationship and that these systems are more concerned with economics than in providing quality patient care. Approximately one quarter of the Y1 trainees at all sites thought that reducing the cost of healthcare is beyond the control of doctors. No Y3 trainee at the PHS believed that reducing costs was beyond the control of doctors. The majority of trainees endorsed routine peer review of clinical decisions to control healthcare costs. Most trainees believed that managed care systems will eventually predominate and that physician independence is being impaired. CONCLUSION: The data suggest that attitudes of internal medicine, family medicine, and pediatric trainees toward various aspects of managed care vary not only by their year of training but also by their training environment. Thus, managed care educational programs for trainees should consider both the baseline attitudes of trainees and characteristics of the training site itself.
We have recently introduced a new approach for induction of transplantation tolerance to donor alloantigens using well-tolerated non-myeloablative conditioning across MHC and xenogeneic barriers in mice. Our regimen consists of no or very low doses of total lymphoid irradiation (TLI), previously shown to be tolerogenic because of profound yet non-myeloablative immunosuppression, followed by deletion of donor-reactive host lymphocytes activated in vivo with donor hematopoietic cells with a single dose of cyclophosphamide. Recipients of immunosuppressive regimen with lower intensity (e.g., no or one single dose of TLI) required a larger inoculum of donor bone marrow cells; the reverse was also true, both regimens resulting in stable mixed chimerism. A combination of low-dose TLI followed by depletion of donor-reactive host cells with cyclophosphamide resulted in consistent engraftment of even low numbers of T-cell-depleted donor-derived hematopoietic cells, known to be much more difficult to engraft, with consistent induction of permanent and donor-specific transplantation tolerance to donor skin allografts with signs of similar success across xenogeneic barriers.
The effect of allogeneic cell therapy on tumor growth was studied in a murine model of mammary carcinoma (4T1) as an experimental model of solid tumors in humans. i.v. inoculation of 4T1 (H-2d) cells into syngeneic mice [BALB/c or (BALB/cXC57BL/6)F1] (F1) carrying the H-2d histocompatible antigens results in tumor colonies in the lungs that finally cause the death of all of the mice. Sublethally irradiated F1 mice were inoculated with 4T1 cells to simulate minimal residual disease and with immunocompetent splenocytes derived from naive donors of F1 (syngeneic), BALB/c (syngeneic to the tumor but semiallogeneic to the host), or C57BL/6 (allogeneic to the tumor and semiallogeneic to the host) mice. The survival of F1 tumor-bearing mice that were treated with allogeneic C57BL/6 splenocytes was significantly prolonged (P < 0.02) compared with hosts given F1 or BALB/c-derived splenocytes that are syngeneic to 4T1 tumor cells. Adoptive transfer of lung cells that were isolated from F1 primary mice inoculated with 4T1 cells and syngeneic BALB/c or F1 splenocytes led to local tumor growth and death in secondary recipients. In contrast, only 1 of 22 secondary recipients developed tumors when inoculated with lung cells derived from F1 mice given allogeneic C57BL/6 splenocytes. All of the 21 secondary hosts survived disease-free for a follow-up time of >200 days. These results indicate that immunocompetent cells allogeneic to the mammary carcinoma cells were able to inhibit tumor development in the primary hosts and to prevent tumor growth in the adoptive recipients, which suggests that allogeneic cell therapy may be an efficient antitumor tool to eradicate minimal residual disease in human solid tumors.
Donor-derived CD4+ T cells may play a role in the development of graft-versus-host disease (GVHD) and graft-versus-leukemia reaction after allogeneic bone marrow transplantation (BMT). Therefore, we evaluated the effect of CD4+ T-cell depletion on GVHD and graft-versus-leukemia reaction after HLA-matched BMT. CD4 depletion was performed using anti-CD4 monoclonal antibodies and immunomagnetic beads, initially in small-scale experiments on bone marrow and granulocyte colony-stimulating factor-mobilized peripheral blood apheresis products. The result was elimination of the CD4+ T cells from both sources (0% and 2+/-1.4% CD4+ cells, respectively). Subsequently, we used this technique for large-scale negative selection of CD4+ T cells from bone marrow grafts of four consenting leukemic patients in relapse (ALL-3, ANLL-1) (M-3, F-1). The large-scale CD4+ T-cell depletion resulted in >98% (n=4) elimination of CD4+ cells. The resulting population included 17.7+/-4.6% CD3+ T cells, 8.9+/-2.5% CD8+ T cells, 0.1+/-0.1% CD16+ natural killer cells, and 2.3+/-3.2% CD34+ hematopoietic progenitor cells. Patients were transplanted with 2.84+/-1.31 x 10(8) viable cells/kg. They received cyclosporine starting on day -1 as GVHD prophylaxis. Engraftment was fast with a white blood cell count of >1 x 10(9)/L on day 13.2+/-0.5, an absolute neutrophil count of >0.5 x 10(9)/L on day 13.8+/-0.5, and a platelet count of >25 x 10(9)/L on day 26.5+/-6.8. Immunological reconstitution was normal, and peripheral blood phenotyping 3 weeks after BMT disclosed 49.0+/-5.0% CD3, 14.3+/-12.4% CD4, and 59.5+/-7.8% CD8 T cells in addition to 17.0+/-3.0% CD16+ and 9.0+/-3.0% CD56 natural killer cells. Three out of four patients developed very early grade IV GVHD beginning on day 12 (10-13) and died 2-4 months after BMT. One patient is alive and well with a follow-up of 36 months. We conclude that selective CD4 T-cell depletion does not prevent GVHD.
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Indomethacin, an inhibitor of cyclo-oxygenase given orally, reduced the tumorigenicity of cancer cells in a non-immunogenic murine model of mammary adenocarcinoma (4T1). In the presence of indomethacin, a dose-dependent immune protection could be induced most effectively by immunizing mice with 1 to 3 doses of irradiated tumor cells inoculated at intervals of 7 days prior to challenge with a tumorigenic cell dose. Three immunizations given without indomethacin resulted in tumor growth in 88% of the recipients, and indomethacin treatment started 28 days prior to the challenge dose and given without immunizations led to tumor onset in 83% of mice. In contrast, tumor was documented only in 12% of mice vaccinated with 3 immunization doses and given concomitantly indomethacin. Moreover, 53% of disease-free survivors resisted a second challenge with a high tumorigenic dose. Induction of an anti-tumor immunity in indomethacin-treated mice was further studied as a therapy for tumor-bearing mice. Complete cure was induced in 50% of mice, and a significant reduction in tumor size as well as prolonged survival time were observed in the remaining animals. Immunostimulation by tumor cell vaccination given in the presence of a tolerable dose of indomethacin, therefore, may be incorporated into immunotherapy protocols to activate an anti-tumor response against residual tumor cells that escaped surgery and/or high-dose chemo/radiotherapy.
Myeloablative conditioning associated with hazardous immediate and late complications is considered as a mandatory first step in preparation for allogeneic blood or marrow transplantation (allogeneic BMT) for the treatment of malignant hematologic disorders and genetic diseases. Immune-mediated graft-versus-leukemia (GVL) effects constitute the major benefit of allogeneic BMT. Therefore, we have introduced the use of relatively nonmyeloablative conditioning before allogeneic BMT aiming for establishing host-versus-graft tolerance for engraftment of donor immunohematopoietic cells for induction of GVL effects to displace residual malignant or genetically abnormal host cells. Our preliminary data in 26 patients with standard indications for allogeneic BMT, including acute leukemia (n = 10); chronic leukemia (n = 8), non-Hodgkin's lymphoma (n = 2), myelodysplastic syndrome (n = 1), multiple myeloma (n = 1), and genetic diseases (n = 4) suggest that nonmyeloablative conditioning including fludarabine, anti-T-lymphocyte globulin, and low-dose busulfan (8 mg/kg) is extremely well tolerated, with no severe procedure-related toxicity. Granulocyte colony-stimulating factor mobilized blood stem cell transplantation with standard dose of cyclosporin A as the sole anti-graft-versus-host disease (GVHD) prophylaxis resulted in stable partial (n = 9) or complete (n = 17) chimerism. In 9 patients absolute neutrophil count (ANC) did not decrease to below 0.1 x 10(9)/L whereas 2 patients never experienced ANC < 0.5 x 10(9)/L. ANC > or = 0.5 x 10(9)/L was accomplished within 10 to 32 (median, 15) days. Platelet counts did not decrease to below 20 x 10(9)/L in 4 patients requiring no platelet support at all; overall platelet counts > 20 x 10(9)/L were achieved within 0 to 35 (median 12) days. Fourteen patients experienced no GVHD at all; severe GVHD (grades 3 and 4) was the single major complication and the cause of death in 4 patients, occurring after early discontinuation of cyclosporine A. Relapse was reversed by allogeneic cell therapy in 2/3 cases, currently with no residual host DNA (male) by cytogenetic analysis and polymerase chain reaction. To date, with an observation period extending over 1 year (median 8 months), 22 of 26 patients (85%) treated by allogeneic nonmyeloablative stem cell transplantation are alive, and 21 (81%) are disease-free. The actuarial probability of disease-free survival at 14 months is 77.5% (95% confidence interval, 53% to 90%). Successful eradication of malignant and genetically abnormal host hematopoietic cells by allogeneic nonmyeloablative stem cell transplantation represents a potential new approach for safer treatment of a large variety of clinical syndromes with an indication for allogeneic BMT. Transient mixed chimerism which may protect the host from severe acute GVHD may be successfully reversed postallogeneic BMT with graded increments of donor lymphocyte infusions, thus resulting in eradication of malignant or genetically abnormal progenitor cells of host origin.
We studied the effect of central line catheters on thrombus formation in the right atrium (RA), including the incidence and echocardiographic characteristics of the catheter-associated thrombus as well as possible clinical implications in patients. We prospectively studied 55 patients by transesophageal echocardiography within 1 week after Hickman catheter implantation and on a follow-up study at 6 to 8 weeks. We succeeded in imaging the catheter tip in 48 of the 55 patients (87%). In the baseline study 13 had the tip placed in the RA, eight at the superior vena cava-atrium junction, and 27 in the superior vena cava. An abnormal mass, consistent with a thrombus, was found in 12.5% of the patients, all of which were seen within the 13-patient (46%) group with the Hickman catheter tip placed in the RA. Hickman catheter insertion is associated with high incidence (12.5%) of early formation of RA thrombus. The formation of these thrombi is asymptomatic and highly associated (p < 0.001) with the catheter tip position in the RA, in contrast to their positioning in the superior vena cava or in its junction with the right atrium. On the basis of these findings, we recommend that special attention and effort be given to placing of the catheter tip in the superior vena cava and avoiding the RA during the implantation procedure.
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Multiple injections of intact irradiated BCL1 cells, a murine B-cell leukemia/lymphoma can trigger a dose-dependent anti-tumor immune response in naive syngeneic mice. The ability to induce anti-BCL1 immunity and the effect of various cell-modifications on BCL1 tumorigenicity and immunogenicity was evaluated. Newcastle disease virus (NDV) infection or transfer of cytokine genes by both retroviral and Adeno 5 vectors affect neither tumorigenicity nor immunogenicity of BCL1 cells given as a non-immunogenic cell-dose. New ways will have to be developed to elicit a reliable and reproducible anti-tumor effect in spontaneously arising and non-immunogenic hematological malignancies.
Post-transplant leukemic relapse remains the major problem following autologous bone marrow transplantation (ABMT). One possible approach to reducing the relapse rate is to intensify pre-transplant conditioning. Thiotepa (TTP) is an alkylating agent that has been used mainly in breast and ovarian cancer with 20-50% response rates. This report presents our results on 33 patients with acute leukemia (acute myeloblastic leukemia (AML) 27 patients, acute lymphoblastic leukemia (ALL) six patients) who underwent ABMT following conditioning with busulfan (BU), 4 mg/kg x 4 days (days -8 to -5), TTP 5 mg/kg x 2 days (days -4, -3) and cyclophosphamide (CY) 60 mg/kg x 2 days (days -2, -1). Of the 33 patients, 22 were males and 11 females, of median age 24 (1-55) years. Twenty-eight patients were transplanted in complete remission (AML 26; ALL 2) while 5 (AML 1; ALL 4) were in early relapse. Twenty-nine additional AML patients (15 females, 14 males) of median age 22 (2-48) years, who underwent ABMT following a standard BU-CY conditioning regimen (25 in complete remission and four in relapse) served as historical controls. There were no significant differences between the study and control groups with respect to patient age, sex, diagnosis, stage of disease, FAB classification, and prior chemotherapy, at ABMT. Overall survival, disease free survival (DFS), and relapse rate at 72 months were 33, 33 and 61%, respectively, for the study group, and 38, 34.5 and 52%, respectively, for the historical controls. Engraftment and transplant related toxicity also did not differ significantly in the two groups. In conclusion, TTP appears to have made no substantial improvement to the outcome of ABMT for acute leukemia.
A 2.5-year-old girl with neurogenic Gaucher's disease was transplanted with donor bone marrow from her HLA-compatible 12-year-old brother whose marrow was harvested 30 min post-mortem, after he suffered a severe head and neck injury. The marrow was stored in liquid nitrogen for 30 days prior to infusion. The post-transplantation period was uneventful with good engraftment and no signs of graft-versus-host disease. Currently, 6 months post-allogeneic bone marrow transplantation (alloBMT), analysis of both bone marrow and blood samples by PCR documented only cells of donor origin. This case demonstrates the feasibility of cadaveric marrow as a source of donor cells. To our knowledge, this patient is the only survivor of alloBMT from a cadaveric donor.
Relapse is the major obstacle for successful transplantations in lymphoma. One of the ways to reduce relapse rates is to intensify immune-mediated effector mechanisms. Graft-versus-lymphoma may be achieved either by administration of cytokines or by allogeneic cell-mediated adoptive immunotherapy. The use of allogeneic non-myeloablative stem cell transplantation (SCT) is another option which may be applicable to all age groups. It remains to be seen whether non-myeloablative SCT will result in a lesser degree of relapse and higher disease-free survival in lymphoma patients.
The Doctoring curriculum at the University of California, Los Angeles, UCLA School of Medicine covers all four years of medical school. Its goal is to train physicians to give care that is compassionate, humanistic, high-quality, and evidence-based through a longitudinal, interdisciplinary curriculum with integration of learning experiences within and between years and with more emphasis on certain topics that had been previously neglected (e.g., advanced physical diagnosis, nutrition, public health, ethics). The curriculum operates alongside the traditional one, but strong attempts are made to link the two curricula. The authors describe the gradual introduction of the Doctoring curriculum, the sometimes formidable barriers that were encountered and in some cases still exist (e.g., some faculty and student resistance, need to find funds, faculty recruitment and retention). Active, interested faculty are essential, and intensive faculty development is needed. A detailed description of each year's courses and teaching approaches is given. Year one focuses on interpersonal communication, the medical interview, human development and behavior, and the role of the community in health care; year two, on clinical reasoning, physical diagnosis skills, population medicine, and ethics; year three, on clinical problem solving, health services, professionalization issues, and prevention; and year four (which is elective), on medical education and leadership. The methods of evaluating students, faculty, and the curriculum itself are described and assessed. The authors conclude with a review of plans, prospects, and ongoing problems.
Immunocompetent donor-derived T lymphocytes play a crucial role in the elimination of residual leukemic cells post allogeneic bone marrow transplantation. Because this graft versus leukemia (GVL) effects is absent after autologous stem cell transplantation (ASCT), a high rate of relapse ensues. We introduced cell-mediated immunotherapy at the stage of minimal residual disease in lymphoma patients to help effect a GVL-like reaction by adoptive transfer of immunocompetent human leukocyte antigen-matched donor peripheral blood lymphocytes (PBL). Thirteen consecutive patients with high-risk lymphoma were treated with allogeneic cell therapy (AlloCT) after having undergone ASCT. In the absence of graft-versus-host disease, cell therapy-induced graft-versus-lymphoma reaction was amplified by human recombinant interleukin 2 (rIL-2) during 3 days to activate donor PBL in vivo, followed by infusion of in vitro rIL-2 activated donor lymphocytes combined with 3-day rIL-2 therapy. Nine of the patients underwent the treatment protocol well. In the four other patients, in whom the AlloCT resulted in marrow aplasia due to elimination of host hematopoietic cells, treatment with donor marrow cell infusion without further conditioning was performed. Adoptive cell therapy in the form of AlloCT may turn out to be an effective therapeutic modality for the treatment of resistant residual disease in lymphoma patients.