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Biomedical subjects

M K Brenner

Publications and source records attributed to M K Brenner.

At least 109 records · Page 6Linked to original sources
PubMed1994

Gene marking to improve the outcome of autologous bone marrow transplantation.

The neomycin resistance gene in a retroviral vector has been used to mark the marrow of patients receiving autologous bone marrow transplantation for neuroblastoma and acute myeloid leukemia. We have shown that the marker gene can be detected in the resurgent malignant cells at the time of relapse, directly demonstrating that tumorigenic cells contaminate "remission" marrow. We have also shown effective gene transfer to normal primitive progenitor cells and demonstrated a long lasting contribution of the infused marrow to hematopoiesis. The gene marking technique is now being used to evaluate the efficacy of purging and the impact of growth factor treatment on long and short term hematopoietic reconstitution.

Acute Disease↗
PubMed1994

XomaZyme-CD5 immunotoxin in conjunction with partial T cell depletion for prevention of graft rejection and graft-versus-host disease after bone marrow transplantation from matched unrelated donors.

Patients who receive bone marrow transplants from unrelated donors have a high incidence of graft-versus-host disease (GVHD). If the donor marrow is first T cell-depleted, the everity of GVHD declines but the risk of rejection rises. In an attempt to prevent both graft rejection and GVHD, we included an anti-T cell antibody-toxin conjugate (CD-5-Ricin; XomaZyme H65) in the transplant conditioning regimen. After receiving a partially T cell-depleted marrow, patients then received a second course of immunotoxin as additional GVHD prophylaxis. Eight recipients of unrelated donor marrow transplants were studied. All engrafted (ANC > 500 x 10(6)/l by day 15, range 13-20 days). One patient had grade II skin GVHD and one developed grade IV disease but the other six patients had no acute GVHD. However, there was high morbidity and mortality from virus infections associated with a sluggish return of CD4 and CD8 T cells into the normal range. Four patients died from virus disease (CMV, n = 2; EBV, n = 1; adenovirus, n = 1) and the remaining patients had frequent documented viral illnesses during the first year. We conclude that improvement in the outcome of unrelated donor marrow transplantation will require strategies which prevent rejection and GVHD coupled with attempts to accelerate immune reconstitution.

Adolescent↗
PubMed1994

Bronchiolitis obliterans organizing pneumonia (BOOP) in children after allogeneic bone marrow transplantation.

Three pediatric patients of a cohort of 24 who underwent allogeneic bone marrow transplantation (BMT) from matched unrelated or mismatched family member donors developed low grade fever and cough between 2 and 3 months after BMT in the absence of clinical GVHD. Imaging studies revealed bilateral patchy opacities and open lung biopsies revealed the characteristic histological appearance of bronchiolitis obliterans organizing pneumonia. All three patients were treated with steroids and in two patients the syndrome resolved over 1-2 months; the third patient developed progressive pulmonary failure and died 2 weeks after diagnosis. BOOP may be an under-recognized respiratory complication following BMT from a matched unrelated donor or mismatched family member.

Adolescent↗
PubMed1993

Gene marking to determine whether autologous marrow infusion restores long-term haemopoiesis in cancer patients.

The contribution of infused bone marrow cells to long-term haemopoietic recovery in patients undergoing autologous bone marrow transplantation is unknown. Such information would help to clarify the role of this procedure in cancer therapy and would aid in the development of strategies to reduce the risk of subsequent aplasia. By transferring a neomycin resistance marker gene into the marrow cells of 20 patients before transplantation, we were able to trace the pattern of haemopoietic reconstitution postinfusion. The marker gene was present and expressed in all haemopoietic lineages in vivo in 15 of 18 evaluable patients at 1 month post-transplantation, in 8 of 9 patients at 6 months, and in 5 of 5 at 1 year. The marker has remained detectable for up to 18 months--the duration of our study. Our findings indicate that harvested bone marrow consistently contributes to long-term multilineage recovery of haemopoiesis after autologous marrow transplantation in cancer patients. These results provide a rationale for the continued exploration of more ablative preparative regimens with single or sequential autologous marrow transplants.

Adolescent↗
PubMed1993

Correction of Duncan's syndrome by allogeneic bone marrow transplantation.

Duncan's syndrome (X-linked lymphoproliferative disorder) is a fatal immunodeficiency syndrome of unknown aetiology and without cure. We show that allogeneic bone marrow transplantation can correct the lethal immune deficits in a patient with this syndrome. We suggest that the primary abnormality in Duncan's syndrome is in bone-marrow derived cells.

Bone Marrow Transplantation↗
PubMed1993

Gene-marking to trace origin of relapse after autologous bone-marrow transplantation.

Bone marrow harvested for autologous bone-marrow transplantation may contain residual malignant cells even when it is judged to be in remission. Genetic marking and subsequent detection of these cells in recipients would give useful information about the origin of relapse after transplantation. We transferred the neomycin-resistance gene into bone-marrow cells harvested from children with acute myeloid leukaemia in remission. Two patients have relapsed since reinfusion of the marked cells. In both, the resurgent blast cells contained the neomycin-resistance gene marker; thus, remission marrow can contribute to disease recurrence. This method of tracking malignant cells should enable the development of better marrow purging strategies.

Bone Marrow Cells↗
PubMed1993

Interferon gamma inhibits apoptotic cell death in B cell chronic lymphocytic leukemia.

The malignant, CD5+ B lymphocytes of B cell chronic lymphocytic leukemia (B-CLL) die by apoptosis in vitro. This is in contrast to the prolonged life span of the leukemic cells in vivo and likely reflects the lack of essential growth factors in the tissue culture medium. We found that interferon gamma (IFN-gamma) inhibits programmed cell death and promotes survival of B-CLL cells in culture. This effect may also be important in vivo: increased serum levels of IFN-gamma, ranging from 60 to > 2,200 pg/ml, were found in 7 of 10 B-CLL samples tested, whereas the sera of 10 healthy individuals did not contain detectable levels of this cytokine (< 20 pg/ml). High levels of IFN-gamma message were detected in RNA from T cell-depleted B-CLL peripheral blood samples by Northern blot analysis. Synthesis of IFN-gamma by B-CLL lymphocytes was confirmed by in situ hybridization and flow cytometry. The majority of B-CLL cells (74-82%) expressed detectable levels of IFN-gamma mRNA, and CD19+ B-CLL cells were labeled with anti-IFN-gamma monoclonal antibodies. These results show that IFN-gamma inhibits programmed cell death in B-CLL cells and suggest that the malignant cells are able to synthesize this cytokine. By delaying apoptosis, IFN-gamma may extend the life span of the malignant cells and thereby contribute to their clonal accumulation.

Antigens, CD↗
PubMed1993

Transfer of humoral immunity against cytomegalovirus proteins following transplantation of T-cell-depleted allogeneic bone marrow from seropositive donors.

Previous work by Grob et al. [Lancet i: 774, 1987] has demonstrated that allogeneic, T-cell-depleted bone marrow transplant recipients have a better prognosis for reactivated cytomegalovirus (CMV) infection if their donor is also immune. It was proposed that adoptively transferred humoral immunity was responsible for the protective effect of active infection. Immunoblot analysis using purified virions was used here to examine pre- and posttransplant antibody responses of seropositive recipients who had undergone active viral infection after transplantation. Immunoblots were assessed for the numbers of polypeptides recognised and reactivity against individual polypeptides. Immunoblots were also scanned by quantitative densitometry, and the intensity of antibody responses against total viral protein and individual polypeptides was determined. Sera from recipients with immune donors exhibited a secondary-type immune response in terms of both intensity and polypeptide specific pattern of antibody reactivity, compared with those recipients with nonimmune donors. In particular, recipients with immune donors appeared to show a greater reactivity against a protein of M(r) 55,000; this may represent the envelope glycoprotein gB, which is a major target for neutralising antibodies, and might also be utilised for preparing an effective vaccine for CMV.

Antibodies, Viral↗
PubMed1993

Mechanisms of selective killing of neuroblastoma cells by natural killer cells and lymphokine activated killer cells. Potential for residual disease eradication.

Widely disseminated neuroblastoma in children older than infancy remains a very poor prognosis disease. Even the introduction of marrow ablative chemotherapy with autologous rescue has not significantly improved the outlook for these children, presumably because of a failure to eradicate minimal residual disease. One additional approach which may hold promise is the use of immunomodulation with cytokines such as IL2 in the setting of minimal residual disease (MDR), for example after intensive chemotherapy and ABMT. However, considerable variability in the susceptibility of neuroblastoma cells to natural killer (NK) and lymphokine-activated (LAK) killing has been observed, and it is presently unclear how NK and LAK cells recognise neuroblastoma cells. In this paper we examine expression of cell adhesion molecules on neuroblastoma to determine which of these modify interaction with NK and LAK cells. We find that LFA-3 (CD58), the ligand for CD2 is of predominant importance in predicting susceptibility of neuroblastoma to the cytotoxic actions of NK and LAK cells, while expression of ICAM-1 (CD54) may also modify susceptibility. These findings were confirmed by blocking experiments in which co-culture of target cells with ICAM-1 and LFA-3 reduced LAK and NK cytotoxicity. Study of the immunophenotypic features of each patient's neuroblastoma cells before induction of MRD may be valuable in determining the likely effect of IL2 in predicting disease reactivation.

Cell Adhesion Molecules↗
PubMed1993

Gene transfer into human hematopoietic progenitor cells: a review of current clinical protocols.

Recent reviews by Clay Smith (1992) in this journal and by W. French Anderson (1990) and A. Dusty Miller (1992) have described the technologies used for gene transfer, the potential applications of the approach, and the safety issues that require consideration. This review will have a narrower focus. It will deal specifically with current and forthcoming clinical protocols for gene transfer into hemopoietic progenitor cells, because a major goal of gene therapy for malignant and nonmalignant disease is to transfer and express genes on a long-term basis in these cells or their progeny.

Acute Disease↗
PubMed1993

Anti-pan T lymphocyte ricin A chain immunotoxin (H65-RTA) and methylprednisolone for acute GVHD prophylaxis following allogeneic BMT from HLA-identical sibling donors.

Six patients (five children < or = 12 years old and one young adult) underwent allogeneic BMT (not T lymphocyte-depleted) from sex-matched HLA-identical siblings. GVHD prophylaxis consisted of methylprednisolone (30 mg/m2) and anti-pan T lymphocyte ricin A chain immunotoxin (H65-RTA) (0.1 mg/kg) administered daily for 12 consecutive doses. H65-RTA was initiated at day +5 (n = 4) or day +2 (n = 2). All patients engrafted. Despite receiving the planned GVHD prophylaxis, all patients developed moderate to severe acute GVHD; five patients developed Grade III/IV GVHD. Four patients died 34 to 78 days post-transplant; GVHD was a contributory cause of death in each case. H65-RTA as used in this study was ineffective for the prophylaxis of acute GVHD.

Adult↗
PubMed1992

Bone marrow transplant recipients have defective MHC-unrestricted cytotoxic responses against cytomegalovirus in comparison with Epstein-Barr virus: the importance of target cell expression of lymphocyte function-associated antigen 1 (LFA1).

Cytomegalovirus (CMV) remains the most common single infective cause of death following allogeneic bone marrow transplantation (BMT) from major histocompatibility complex (MHC)-identical siblings, whereas Epstein-Barr virus (EBV)-related disease is infrequent. We show here that MHC-unrestricted cytotoxic effector cells in the peripheral blood of BMT recipients are highly effective at killing EBV-infected target cells, but are inactive against CMV-infected target cells. Differential cytotoxicity is associated with disparate target structure expression. Although both EBV- and CMV-infected target cells express viral antigens, it is only those infected with EBV that express the adhesion molecule lymphocyte function-associated antigen 1 (LFA1; CD11a/18). Thus, EBV-infected target cells are able to interact with the principal LFA1 ligand, intercellular adhesion molecule 1 (ICAM1; CD54), which is expressed on posttransplant peripheral blood mononuclear (PBM) effector cells. CMV-infected target cells cannot utilize this ligand. Posttransplant cytotoxicity against EBV-infected target cells is abolished by target and effector cell blockade with monoclonal antibodies (MoAbs) to LFA1 and ICAM1, respectively, demonstrating the functional relevance of this additional ligand interaction. These results provide an illustration both of the importance and of the limitations of MHC-unrestricted cytotoxicity in vivo and may explain the frequency of CMV disease and the relative rarity of EBV-related disease following allogeneic transplantation from MHC-matched siblings. The increased immunosuppression used following MHC-mismatched/matched unrelated-donor BMT may cause this MHC-unrestricted defense mechanism to fail and may contribute to the greatly increased incidence of EBV lymphoproliferative syndrome in these patients.

Adolescent↗