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J F Apperley

Publications and source records attributed to J F Apperley.

At least 91 records · Page 5Linked to original sources
PubMed1994

In vitro proliferation by cells mobilized into the peripheral blood for collection and autologous transplantation.

We have investigated the properties of mobilized, cryopreserved, peripheral blood stem cells (PBSC), collected by leukapheresis over a period of 5 days, from eight myeloma patients in clinical remission. Cells were mobilized by treatment with cyclophosphamide and granulocyte colony-stimulating factor (G-CSF), and each day's collection was evaluated for its content of CD34+ cells, colony-forming units granulocyte/macrophage (CFU-GM), and plastic-adherent pre-CFU-GM. Peak values for these three parameters were observed at different times in different patients. There was no correlation between CD34+ content and CFU-GM, but there was some (r = 0.65) between CD34 numbers and colonies generated from a delta assay initiated using plastic-adherent pre-CFU-GM. In suspension cultures, the cells grew exponentially for 50 days. Thereafter, they did not divide, although they remained viable in culture for up to 1 month longer. Suspension cultures of PBSC grown with interleukin-3 (IL-3) displayed a predominantly myelomonocytic phenotype, but some megakaryocytes and erythroid cells were observed consistently. These results indicate that pre-CFU-GM in PBSC collections are capable of generating large numbers of clonogenic progeny in liquid culture and are capable of producing multiple lineages of differentiation.

Antigens, CD↗
PubMed1994

Umbilical cord blood progenitor cell transplantation. The International Conference Workshop on Cord Blood Transplantation, Indianapolis, November 1993.

Haemopoietic progenitor cells are present in umbilical cord blood (UCB) and have been used to restore haemopoiesis in children after myeloablative therapy. UCB may possess a number of advantages over bone marrow and peripheral blood as a source of allogeneic progenitor cells, e.g. a lower incidence of graft-versus-host disease and a decreased risk of transmission of infection and there is considerable interest in the establishment of large cord blood banks for use in unrelated transplants. The International Conference Workshop on Cord Blood Transplantation was held in Indianapolis in November 1993 and provided a timely opportunity to review the clinical and laboratory data relating to the use of UCB in transplantation. The results from 34 UCB transplants have been reported to the International Cord Blood Transplant Registry. Engraftment was achieved in 27 of 31 evaluable patients. Graft-versus-host disease > grade 1 occurred only in children transplanted from a one haplotype matched donor; 22 patients survive at a median of 1.5 years. Further sessions at the meeting reviewed the haemopoietic cell content of UCB, the capacity for expansion of early cells and the origin (fetal and/or maternal) and function of lymphoid cells within the graft. The conference ended with a discussion of the practicalities of cord blood banking including collection, cryopreservation, storage, HLA-typing and screening for genetic and infectious diseases.

Adolescent↗
PubMed1993

Outcome for patients who relapse after allogeneic bone marrow transplantation for chronic myeloid leukemia. Chronic Leukemia Working Party. European Bone Marrow Transplantation Group.

We studied the clinical course of 130 chronic myeloid leukemia (CML) patients (89 males and 41 females) in the European Bone Marrow Transplantation Group (EBMT) registry who received transplants before January 1, 1988 and who subsequently had evidence of recurrent leukemia. All patients had received a pretransplant conditioning regimen including total body irradiation (TBI). The first evidence of relapse was cytogenetic only in 74 (57%) patients and hematologic in 56 (43%). The overall actuarial survival from relapse was 36% at 6 years, with a significantly higher proportion of survivors among female patients (53% v 30%; P < .002). In univariate analysis, the 6-year probability of survival was 52% for patients with cytogenetic relapse and 30% for patients relapsing in chronic phase (CP), while no patient who relapsed in advanced phase (AP or BC) survived more than 3.5 years from relapse (P < .0001). The actuarial survival of patients relapsing before 6 months, between 6 and 12 months, and later than 12 months after transplant was 27%, 26%, and 45%, respectively (P < .002). Among patients with cytogenetic relapse, partial or complete disappearance of Ph-positive cells occurred in 40% of untreated patients and in 42% of those treated with interferon (IFN). However, IFN therapy significantly delayed progression toward hematologic disease. Cytogenetic responses were observed in 25% of patients who received IFN for relapse into CP, while only one minor cytogenetic response was reported in patients on conventional chemotherapy. For patients presenting with cytogenetic relapse as well as for those in hematologic relapse, IFN therapy significantly improved the 2-year probability of survival. However, long-term survival for IFN-treated patients in either group was not different from long-term survival in comparable patients not receiving IFN therapy. Twenty-nine patients of this series underwent a second bone marrow transplant (BMT) and the projected survival at 4 years after the second transplant is 28%. In multivariate Cox regression analysis, four factors remained significantly associated with survival: disease phase at relapse (P < .0001), duration of time interval from BMT to relapse (P = .0001), interferon therapy at relapse (P = .0024), and patient sex (P = .0032). This retrospective study provides evidence that some patients who relapse after BMT may benefit from treatment with IFN; a second BMT may offer the chance of cure. Data from this analysis may be useful in designing future prospective trials on posttransplant CML relapse.

Adolescent↗
PubMed1993

Bone marrow transplant for the haemoglobinopathies: past, present and future.

Bone marrow transplantation (BMT) is the only treatment currently available which can cure thalassaemia and sickle cell anaemia. However, it is not without risk and the complications of graft failure, GVHD, veno-occlusive disease, interstitial pneumonitis and infections, together with the toxicity of the conditioning therapy result in a transplant-related mortality in children of 10-20%. For the survivors, long-term sequelae include chronic GVHD, endocrinopathies and an increased incidence of secondary malignancies. The decision to offer BMT to a patient with a haemoglobinopathy must be based on a knowledge of the relative risks of transplant and conventional therapy. However, in sickle cell anaemia, a subset of patients with particularly severe disease can be identified at an early age when the risks associated with BMT are at their lowest. In thalassaemia, chelation therapy can delay the onset of organ damage due to hypertransfusion but is unlikely to prevent it entirely. The results of BMT in children without organ impairment are excellent and BMT must now be considered a real alternative to conventional treatment. Gene therapy is an exciting prospect for the future but recent progress in retroviral gene transfer has been hindered by poor infection efficiencies and expression levels in the target cells. The identification of the positive regulatory elements of both the alpha- and beta-globin genes may resolve some of these problems. Finally, alternative gene delivery systems are being investigated, but the introduction of gene therapy for the haemoglobinopathies into clinical practice may need to await successful gene targeting and replacement.

Anemia, Sickle Cell↗
PubMed1992

Circulating stem cells in mice treated with cyclophosphamide.

Chemotherapy has been used clinically to mobilize hematopoietic progenitor cells into the peripheral blood so that they can be harvested for autologous transplantation. In humans, this is demonstrated by the presence of circulating granulocyte-macrophage colony-forming cells (CFU-GM) and CD34-positive cells, but it has not been possible to confirm the presence of marrow-repopulating stem cells. In this study, we treated mice with 200 mg/kg cyclophosphamide (CY) and measured the numbers of white blood cells, day 12 CFU-S (CFU-S12), and CFU-GM in the peripheral blood. There was a peak in the numbers of CFU-S12 and CFU-GM 8 days after treatment with cyclophosphamide. Peripheral blood cells taken at this time rescued lethally irradiated mice and engraftment of donor cells was confirmed after 140 days in sex mismatched recipients using a Y chromosome-specific probe. In vitro culture of the blood cells harvested after cyclophosphamide showed that they proliferated in suspension cultures for at least a year in the presence of interleukin-3. The cultured cells rapidly lost their abilities to rescue irradiated mice and to form colonies in vitro, but they did not become leukemic. Also, CY-treated mice were irradiated with a leukemogenic dose of x-rays to coincide with peak circulating cell numbers but these animals did not develop an excess of leukemias over mice given irradiation alone.

Animals↗
PubMed1992

Successful use of liposome encapsulated amphotericin to treat invasive aspergillosis following failure of conventional amphotericin.

We describe a case of proven invasive pulmonary aspergillosis in a neutropenic patient in whom disease progression occurred during treatment with conventional amphotericin B despite neutrophil recovery. Treatment with liposomal encapsulated amphotericin B resulted in clinical and radiological improvement and the clearance of aspergillus spores from the sputum.

Amphotericin B↗
PubMed1991

Retroviral gene transfer of human adenosine deaminase in murine hematopoietic cells: effect of selectable marker sequences on long-term expression.

Retroviral-mediated gene transfer of human adenosine deaminase (hADA) provides a model system for the development of somatic gene therapy as a therapy for diseases of bone marrow-derived cells. We have previously demonstrated that hADA can be observed in all hematopoietic lineages in a minority of mice transplanted with bone marrow cells infected with a simplified retroviral vector, ZipPGK-ADA. Here we report a majority of mice (six of eight) demonstrate expression of hADA in the peripheral blood at least 6 months after transplantation with bone marrow infected with this simplified retroviral vector, which contains no selectable marker. The failure to express hADA in two of eight mice was associated with the absence of the recombinant retroviral provirus in DNA prepared from bone marrow cells of these mice apparently due to failure to efficiently infect the reconstituting hematopoietic stem cell. In an effort to preselect bone marrow stem cells containing proviral integrations, we incorporated the selectable marker neo phosphotransferase (NEO) into a retroviral vector encoding hADA, N2/ZipPGK-ADATKNEO, and used G418 selection of infected bone marrow cells before transplantation. In contrast to the simplified retroviral vector, hADA expression in these recipients was short lived (less than 8 weeks), despite the continued presence of intact provirus in DNA prepared from bone marrow of these mice. To determine whether the preselection of bone marrow using G418 was responsible for the lack of sustained hADA expression, we repeated the infection with the N2/ZipPGK-ADATKNEO vector but omitted the G418 selection step. Again, the majority of recipient mice failed to express hADA long term, although the continued presence of provirus in DNA prepared from peripheral blood cell mononuclear cells was clearly demonstrated. Finally, we demonstrate clonal fluctuation of infected stem cells, and observe a temporal correlation between cessation of expression of hADA and the emergence of a dominant stem cell clone between 14 and 20 weeks posttransplantation in one recipient. These data suggest that inclusion of a second transcriptional unit that includes neo phosphotransferase sequences in this simplified vector is associated with decreased expression of the nonselectable ADA sequences.

Adenosine Deaminase↗
PubMed1990

Gene transfer into murine hematopoietic stem cells and bone marrow stromal cells.

The use of recombinant retroviral vectors to transfer genetic sequences into hematopoietic stem cells (HSC) is one approach to somatic gene therapy. Two limitations of such retroviral vectors are the degree of efficiency of transfer into the reconstituting hematopoietic stem cells and the loss of reconstituting ability of hematopoietic stem cells when manipulated in vitro during infection and selection. We have investigated the effects on the efficiency of gene transfer of prestimulation of hematopoietic stem cells by growth factors prior to infection. Prestimulation of bone marrow cells in WEHI-3b-conditioned media improved the efficiency of gene transfer into CFU-S stem cells. The majority of animals transplanted with bone marrow infected after prestimulation with a simplified retrovirus, Zip PGK ADA, demonstrated long-term and stable expression of human adenosine deaminase (ADA) after full hematopoietic reconstitution. In separate experiments, retroviral vectors have been used to transfer the SV40 large T antigen sequences into stromal cells making up the hematopoietic microenvironment. Stromal cells expressing large T antigen are immortalized, and some support the maintenance of day 12 CFU-S (CFU-S12) and reconstituting hematopoietic stem cells in vitro for up to 4 weeks. Such immortalized stromal cell lines provide an in vitro hematopoietic microenvironment which may allow prolonged in vitro manipulations during infection and selection of hematopoietic stem cells without loss of reconstituting ability. We are using immortalized stromal cell lines resistant to deoxycoformycin (dCF) to select transduced murine HSC containing human ADA in vitro. The use of recombinant retroviral vectors provides a promising approach to correction of human diseases involving bone marrow cells.

Animals↗
PubMed1990

Bone marrow transplantation for chronic myeloid leukemia: the use of histocompatible unrelated volunteer donors.

We treated 17 patients with chronic myeloid leukemia (CML) by bone marrow transplantation using marrow from human leukocyte antigen (HLA)-matched unrelated donors. Patients were conditioned with a combination of in vivo monoclonal antibodies, chemotherapy with daunorubicin (n = 7) or busulfan (n = 10) and cyclophosphamide, and both total body and total lymphoid irradiation. Donor marrow was depleted of T cells by incubation with monoclonal antibodies of the Campath series. Fourteen (88%) of 16 evaluable patients had sustained engraftment. Four (27%) of the 15 evaluable patients developed acute graft-versus-host disease (GVHD) of grade II or greater, and 4 of 12 evaluable patients developed chronic GVHD. Three patients developed hematological and two developed cytogenetic evidence of relapse. Eight patients (47%) survive at a median follow-up of 32 months (range 10-51 months), giving an actuarial survival of 44%. Five patients remain alive without evidence of hematological or cytogenetic relapse, giving an actuarial disease-free survival of 27%. Pneumonitis caused or contributed to death in six of the nine patients who died. We conclude that T-cell depletion can prevent the severest forms of GVHD but also increases the risk of relapse after transplant with unrelated donors, as it does with HLA-identical siblings. Nevertheless the use of matched unrelated donors should be considered for CML patients who lack HLA-identical siblings.

Adolescent↗
PubMed1989

Total lymphoid irradiation preceding bone marrow transplantation for chronic myeloid leukaemia.

Between August 1985 and October 1987 we treated 35 patients with chronic myeloid leukaemia (CML) by high dose chemotherapy, total body irradiation (TBI) (1000 or 1200 cGy, n = 31) and total lymphoid irradiation (TLI) (800 or 600 cGy, n = 35) preceding allogeneic bone marrow transplantation (BMT). Both TBI and TLI were given at 200 cGy/fraction. Twenty-three patients had HLA-identical sibling donors, nine patients had HLA-matched but unrelated donors, and three partially HLA-mismatched donors. Twenty-two patients received T-cell depleted marrow. The addition of TLI to the standard protocol did not add greatly to the toxicity. Four patients had recurrent leukaemia before engraftment was evaluable. The other 31 patients engrafted and no graft failed. Twenty-two patients survive at a median time from transplant of 305 days (range 81-586 days). Fourteen have no evidence of disease; eight have or had only cytogenetic evidence of leukaemia. We conclude that the addition of TLI to pretransplant immunosuppression increases the probability of reliable engraftment in patients receiving T-cell depleted marrow. This benefit is not associated with significantly increased toxicity.

Adolescent↗
PubMed1989

Long-term expression of human adenosine deaminase in mice transplanted with retrovirus-infected hematopoietic stem cells.

Long-term stable expression of foreign genetic sequences transferred into hematopoietic stem cells by using retroviral vectors constitutes a relevant model for somatic gene therapy. Such stability of expression may depend on vector design, including the presence or absence of specific sequences within the vector, in combination with the nature and efficiency of infection of the hematopoietic target cells. We have previously reported successful transfer of human DNA encoding adenosine deaminase (ADA) into CFU-S (colony-forming unit-spleen) stem cells using simplified recombinant retroviral vectors. Human ADA was expressed in CFU-S-derived spleen colonies at levels near to endogenous enzyme. However, because of the lack of an efficient dominant selectable marker and low recombinant viral titers, stability of long-term expression of human ADA was not examined. We report here the development of an efficient method of infection of hematopoietic stem cells (HSC) without reliance on in vitro selection. Peripheral blood samples of 100% of mice transplanted with HSC infected by this protocol exhibit expression of human ADA 30 days after transplantation. Some mice (6 of 13) continue to express human ADA in all lineages after complete hematopoietic reconstitution (4 months). The use of recombinant retroviral vectors that efficiently transfer human ADA cDNA into HSC leading to stable expression of functional ADA in reconstituted mice, provides an experimental framework for future development of approaches to somatic gene therapy.

Adenosine Deaminase↗
PubMed1989

Slow evolution of chronic myeloid leukaemia relapsing after BMT with T-cell depleted donor marrow.

Thirty-three patients with Philadelphia positive (Ph+) chronic myeloid leukaemia (CML) treated in chronic phase by bone marrow transplantation (BMT) with T-cell depleted HLA-identical sibling marrow were evaluable for relapse at a median follow up of 41 months (range 16-59 months). Twenty-six (78%) had Ph+ marrow metaphases demonstrated at some time post BMT. The subsequent pattern of disease was variable. In 15 of these cases haematological relapse occurred within 24 months of BMT. Four patients proceeded to haematological relapse more slowly. Seven patients had only cytogenetic evidence of relapse. Of the 19 patients with haematological relapse, five received second transplants and two survive; 13 of the other 14 survive in chronic phase at median times from allografting and from recognition of haematological relapse of 41 months (range 25-59 months) and 18 months (range 5-36 months) respectively. For these 13 patients disease progression after relapse seems to be relatively indolent. In the four patients we could study, blood lymphocytes were almost all of donor origin. We suggest that even in patients with cytogenetic or haematological evidence of relapse after T-cell depleted BMT, leukaemic cell proliferation may still be restrained to some extent by a graft-versus-leukaemia effect mediated by donor-derived lymphoid cells.

Adult↗
PubMed1989

The effect of cytomegalovirus on hemopoiesis: in vitro evidence for selective infection of marrow stromal cells.

We studied the effects of adding cytomegalovirus (CMV) in vitro to normal human bone marrow mononuclear cells (BM-MNCs), committed myeloid progenitor cells, primitive myeloid blast-colony forming cells, and pre-formed marrow stromal cell monolayers in order to shed light on the mechanism by which hemopoiesis is suppressed in patients who acquire systemic CMV infection after allogeneic bone marrow transplantation. Incubation of BM-MNCs or committed progenitor cells with laboratory strain AD169 or wild strain CMV had no significant effect on total colony numbers or the morphology of component cells. CMV mRNA was not identified by in situ hybridization. In contrast, incubating marrow stromal monolayers with CMV produced specific cytopathic effects in fibroblasts and adipocytes and reduced the capacity of the stromal layers to support the proliferation of primitive myeloid progenitor cells. We conclude that CMV infection may impair hemopoiesis in vivo by a direct effect on the cellular components of the marrow stroma.

Bone Marrow↗
PubMed1988

Bone marrow transplantation for chronic myeloid leukaemia in first chronic phase: importance of a graft-versus-leukaemia effect.

We analysed the incidence of graft failure, graft-versus-host disease (GVHD) and relapse of leukaemia in 208 patients undergoing allogeneic bone marrow transplantation (BMT) for chronic myeloid leukaemia in chronic phase in eight transplant centres in Europe and the United States. 106 patients received unmanipulated donor bone marrow (Group 1) and 102 patients received marrow depleted of T-cells by incubation with the monoclonal antibodies Campath-1 or CT-2 and complement (Group 2). The incidence of graft failure was higher and of GVHD was lower in Group 2 than in Group 1. Relapse of leukaemia occurred more frequently in patients in Group 2 than in Group 1 (17 v. 2, P less than 0.001). Multivariate analysis showed that the following factors were associated with an increased risk of relapse: the use of T-cell depletion, the absence of GVHD and a high platelet count at the time of admission for transplant. The findings support the concept that a graft-versus-leukaemia effect mediated by T-lymphocytes is important for cure of leukaemia after BMT.

Adolescent↗
PubMed1988

Pulmonary function after bone marrow transplantation for chronic myeloid leukaemia.

Pulmonary function was measured before and at intervals after treatment in 44 patients who received a bone marrow transplant for chronic myeloid leukaemia in the chronic phase. All patients were treated with cytotoxic drugs, total body irradiation, and post-graft immunosuppression. Thirty four patients surviving for 12 months were followed at three monthly intervals and 16 patients for 24 months. Fifteen patients received unmanipulated donor marrow cells and 29 patients received donor marrow cells depleted of lymphocytes ex vivo with the monoclonal antibody Campath-1. The 21 patients treated early in this study received 10 Gy of total body irradiation whereas the 23 patients treated more recently, who were all T lymphocyte depleted, received 12 Gy. Pretransplant lung function for the group was normal and was similar in survivors (n = 34) and nonsurvivors (n = 10), and in smokers (n = 8) and non-smokers (n = 36). (Carbon monoxide transfer factor--TLCO) was under 75% of predicted normal in nine patients before transplantation. TLCO, carbon monoxide transfer coefficient (KCO), FEV1, and vital capacity (VC) values were lower 6 and 12 months after bone marrow transplant than initially. The greatest decline was in TLCO, from an initial value of 89% to 66% at 6 and 70% at 12 months. The 16 longer term survivors showed significant recovery of function between 6 and 24 months after bone marrow transplant for TLCO, KCO, and VC, the increase ranging from 6.3% to 7.3% predicted. Airflow obstruction (FEV1/VC ratio less than 70%) developed in one patient. The major factors associated with deterioration in pulmonary function at 6 and 12 months after transplantation in the 34 survivors (stepwise multiple regression analysis) were (a) transplantation with T cell depleted donor marrow (p less than 0.005) and higher total body irradiation dose (p less than 0.02) with a fall in KCO and an increase in the FEV1/VC ratio; (b) chronic graft versus host disease with a fall in VC (p less than 0.01); and less fall in KCO (p less than 0.01); and (c) acute graft versus host disease with a fall in FEV1 (p less than 0.01). It is considered that most patients who survive the short term risks of bone marrow transplant have only minor long term impairment of pulmonary function.

Adolescent↗
PubMed1988

Cytomegalovirus: biology, clinical features and methods for diagnosis.

Cytomegalovirus (CMV) infections remain a major obstacle to the successful outcome of bone marrow transplantation (BMT). The clinical manifestations of CMV-induced disease are many and varied and may mimic other disease processes commonly seen after BMT. The development of effective strategies for the prevention and treatment of such infections requires an understanding of the life cycle of the virus. In this review we discuss the molecular structure of CMV, the modes of replication and transmission, and the biology of the development of latency and reactivation. The recent availability of potentially effective anti-CMV drugs emphasizes the need for rapid diagnostic techniques which permit the initiation of treatment early in the disease. We review the diagnostic methods in common use and compare the newly developed rapid assays with the standard techniques of viral isolation and serological responses, with particular reference to their use in marrow transplant recipients.

Bone Marrow Transplantation↗