37 research outputs found
In-Vitro Effects of Cytokines on Normal and Myeloid Leukaemic Haemopoiesis
The growth of chronic myeloid leukaemic (CML) and acute myeloid leukaemic (AML) cells in vitro and their response to various cytokines were studied and compared to normal peripheral blood and bone marrow cells. In normal mononuclear cells (MNC) the three cytokines [granulocyte colony-stimulating factor (G-CSF), granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-3 (IL-3)] had no appreciable difference at stimulating (colony-forming unit granulocyte-macrophage) CFU-GM-formation. By contrast, G-CSF was a more potent stimulator of CFU-CML, than GM-CSF or IL-3. Interleukin-4 (IL-4) augmented G-CSF-induced colony formation of CML chronic phase cells. Transforming growth factor beta1 (TGFbeta1) reduced G-CSF-induced CFU-CML from CML chronic phase (p< 0.005) and blast transformation MNC, but had no effect on normal CFU-GM stimulated by G- CSF. The growth of CML mononuclear cells in vitro could not be correlated to the white cell count or percentage of CD34+ cells present. The mechanisms for the inhibitory effects of TGFbeta1 on CML cells were studied using in-situ hybridisation techniques to demonstrate the expression of the G-CSF and IL-4 receptors. The results suggest that this response is more likely to be due to a difference in signal transduction or protein synthesis rather in transcription
Increased risk for myelodysplastic syndrome in individuals with glutathione transferase theta 1 gene (GSTT1) defect
Adoptive transfer of cytomegalovirus-specific CTL to stem cell transplant patients after selection by HLA–peptide tetramers
Stem cell transplantation is used widely in the management of a range of diseases of the hemopoietic system. Patients are immunosuppressed profoundly in the early posttransplant period, and reactivation of cytomegalovirus (CMV) remains a significant cause of morbidity and mortality. Adoptive transfer of donor-derived CMV-specific CD8+ T cell clones has been shown to reduce the rate of viral reactivation; however, the complexity of this approach severely limits its clinical application. We have purified CMV-specific CD8+ T cells from the blood of stem cell transplant donors using staining with HLA–peptide tetramers followed by selection with magnetic beads. CMV-specific CD8+ cells were infused directly into nine patients within 4 h of selection. Median cell dosage was 8.6 × 103/kg with a purity of 98% of all T cells. CMV-specific CD8+ T cells became detectable in all patients within 10 d of infusion, and TCR clonotype analysis showed persistence of infused cells in two patients studied. CMV viremia was reduced in every case and eight patients cleared the infection, including one patient who had a prolonged history of CMV infection that was refractory to antiviral therapy. This novel approach to adoptive transfer has considerable potential for antigen-specific T cell therapy
Chloroma (aleukaemic leukaemia cutis) initially diagnosed as cutaneous lymphoma
A 65-year-old man presented in 1997 with a nodule on his back; histology showed apparent high grade T-cell lymphoma, treated after excision with radiotherapy. He relapsed with lesions on the thigh and buttock in 1998 and was treated with CHOP chemotherapy with a complete response. Further relapse occurred in 1999 with a nodule on his thigh again; he received CNOP (doxorubicin substituted with mitozantrone). At no stage was there clinical, bone marrow or radiological evidence of extra cutaneous disease. In November 2000 he presented with widespread indurated plaques and violaceous nodules. Biopsies repeated with extensive immunohistological staining diagnosed aleukaemic leukaemia cutis. Our patient was diagnosed with cutaneous T-cell lymphoma (CTCL) on the basis of clinical and haemotoxylin & eosin appearances. The correct diagnosis was made after extensive immunohistological studies (including myeloid markers) of repeat biopsies. This case illustrates the importance of diagnostic review in atypical CTCL. There is a high incidence of progression to acute myeloid leukaemia
Burkitt's lymphoma: a single centre experience with modified BFM protocol
Burkitt's lymphoma is a rare aggressive lymphoma, which responds poorly to standard chemotherapy regimens used to treat high-grade non-Hodgkin's lymphoma (NHL). The use of intensive chemotherapy protocols using alkylating agents and intensive CNS prophylaxis has dramatically altered prognosis. We have treated eight patients with Burkitt's lymphoma with a modified BFM protocol. The dose of methotrexate was reduced from 5 g/m2 to 1.5 g/m2 with the aim of reducing toxicity. Seven patients received a total of six cycles of chemotherapy each and one patient received five cycles of chemotherapy. Each cycle included high-dose methotrexate, an alkylating agent (ifosphamide or cyclophosphamide) and two triple intrathecal injections of chemotherapy. Two patients with bulky abdominal disease in addition received an autologous stem cell transplant. The regimen was well tolerated with minimal toxicity. At a median follow-up of 16 months (range 10-28), six of the eight patients (75%) were alive and in complete remission. Two patients relapsed, one 24 months post-BFM chemotherapy and the other 1-month post-autologous stem cell transplantation and 2 months post-BFM chemotherapy
CD8+ T cells specific for cancer-germline gene antigens are found in many patients with multiple myeloma and their frequency correlates with disease burden
The expression of cancer germline antigens (CGAgs) is normally restricted to the testis but is also present in many types of malignant cells including plasma cells from patients with myeloma. Because T-cell immune responses to CGAg have been identified in patients with solid tumors, this may offer a novel target for immunotherapy in patients with myeloma. We have used 12 peptide epitopes from a range of CGAgs to screen for CGAg-specific T cells in blood from patients with multiple myeloma at various stages of their disease. T cells from 15 of 37 patients responded to one or more CGAg peptides and the magnitude of the CGAg-specific CD8+ T-cell response ranged between 0.0004% and 0.1% of the total CD8+ T-cell pool. Serial analyses showed that these immune responses were detectable in individual patients at multiple time points during the course of their disease. In patients undergoing treatment or in disease relapse, the magnitude of the CGAg-specific T-cell response was positively correlated with the level of paraprotein. Functional T cells specific for CGAgs are therefore present in a proportion of patients with multiple myeloma and offer the possibility of a novel approach for immunotherapy in this disease
Intensifying methotrexate (MTX) dosage reduces treatment failure in adults with burkitt or burkitt-like leukaemia/lymphoma (BL) treated with an adapted BFM protocol.
High-hyperdiploidy in Philadelphia positive adult acute lymphoblastic leukaemia: Case-series and review of the literature
Patients with Philadelphia positive (Ph(+)) adult acute lymphoblastic leukaemia (ALL) have a poor prognosis. Stem cell transplantation (SCT) is increasingly being recognised as the treatment of choice in eligible patients with Ph(+)ALL, but disease-relapse remains a problem in a proportion of patients prior to and after SCT. Genetic abnormalities in addition to the Ph chromosome may influence the biology and clinical course of ALL, but there are not many studies on the potential genetic heterogeneity of adult Ph(+)ALL and clinical outcomes. Here, we report on five patients with ALL who were double Ph(+) and also had a high-hyperdiploid karyotype (Ph(+)/hyperdiploid) at diagnosis. In contrast to the presence of the Ph(+) chromosome, high-hyperdiploidy (>50 chromosomes) as the sole karyotypic abnormality in ALL is associated with a favourable clinical outcome. In our series, four patients with a Ph(+)/hyperdiploid karyotype achieved a cytogenetic remission after induction chemotherapy and proceeded to stem cell transplantation (SCT). The fifth had five subclones including Ph(+)/hyperdiploid, as well as those that were only Ph(+); the latter emerged as the dominant clone after induction therapy and the patient died of disease-relapse. Of the patients who underwent SCT, only one relapsed, but achieved a durable remission with donor lymphocyte infusions. Thus, it is conceivable that the presence of high-hyperdiploidy as an additional karyotypic abnormality may confer a better prognosis to Ph(+)ALL, presumably by altering the kinetics of Ph(+) neoplastic cells. We have discussed these results in the context of recent studies on the significance of high-hyperdiploidy in Ph(+) adult ALL
