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Biomedical subjects

E Dorey

Publications and source records attributed to E Dorey.

45 records · Page 3Linked to original sources

Myeloablative therapy with autologous bone marrow transplantation as consolidation therapy for recurrent follicular lymphoma.

PURPOSE: To assess myeloablative therapy with autologous bone marrow transplantation (ABMT) in younger patients with follicular lymphoma in the hope of prolonging remission duration and survival. PATIENTS AND METHODS: Since June 1985, 64 patients with follicular lymphoma have received cyclophosphamide (CY) 60 mg/kg x 2 and total-body irradiation (TBI) 2 Gy x 6 supported by ABMT as consolidation of second or subsequent remission. The marrow mononuclear cell (MNC) fraction was treated in vitro with three cycles of the monoclonal antibody (MAb) anti-CD20 and baby rabbit complement before cryopreservation. At the time of treatment, 34 patients were in complete remission (CR), and 30 had residual disease present. RESULTS: The median time to engraftment was 28 days (range, 15 to 46) for both a neutrophil count greater than 0.5 x 10(9)/L and a platelet count greater than 20 x 10(9)/L. Engraftment did not occur in one patient who died at 12 weeks, and three patients (excluded from the range) have had delayed recovery (> 6 months) of RBCs and platelets. Fifty two patients are alive; three died as a consequence of the transplant procedure, two died in remission from other causes, and seven died of recurrent lymphoma. There was a significant correlation between survival and the total number of episodes of treatment required during the course of the illness (< or = to three v > three, P = .01). With a median follow-up duration of 3 1/2 years, 35 patients continue in remission between 1 and 8 years, and 24 have developed recurrent lymphoma, five with evidence of transformation to high-grade histology. Freedom from recurrence did not correlate with the time from diagnosis, the number of previous treatments, the presence or absence of residual disease at the time of treatment, or during which specific remission the treatment was given (second v > second). However, comparison with an age-matched, remission-matched, historical control group shows a significant advantage in favor of treatment with CY plus TBI plus ABMT (P = .001); currently, there is no difference in survival. CONCLUSION: These results are encouraging, although preliminary; it remains to be established whether this treatment prolongs survival.

Adult↗

Generation of cytotoxic T lymphocytes from peripheral blood of leukaemic patients.

Peripheral blood mononuclear cells from 13 patients with acute leukaemia were used to establish long-term interleukin-2-dependent cytotoxic T lymphocytes. Cells were grown in RPMI medium containing interleukin-2 (IL-2, 100 U/ml) and 2.5% conditioned medium prepared by activating normal lymphocytes with phytohaemagglutinin. Proliferation of IL-2-dependent CD3-positive lymphocytes was seen in 1 of 2 acute lymphocytic leukaemia cases (ALL), 1 of 4 acute myelogenous leukaemia cases (AML) (M1) and 8 of 8 more differentiated AML. In 2 cases with detectable leukaemic cell markers (1 ALL and 1 AML) passageable cells were developed, that expressed normal T cell phenotypes (namely CD3, CD4 and CD8) at the expense of leukaemic cells. In 1 of 2 cases, long-term IL-2-cultured cells showed specific cytotoxic activity against autologous leukemic cells. The percentage killing against autologous and two allogeneic target cell lines at a 50/1 effector/target (E/T) ratio was 42%, 9% and 19% respectively. Similarly the cytotoxic activity of IL-2 activated from 4 different individuals against conventional tumour targets K562 and Daudi at a ratio of 50/1 was 29%-68% (median = 55%) and 34%-78% (median = 61%) respectively. It was also found that this killing potential of the activated cells was maintained for as long as culture was continued (median 23 days, range 17-75 days). The mechanism(s) of T cell proliferation at the expense of leukaemic blast cells in the case of a minority of leukaemic patients and the possible clinical therapeutic potential of these cells following in vitro IL-2 activation deserve further investigation.

Antigens, CD↗

Inhibition of human neutrophil migration in vitro by low-molecular-mass products of nontypeable Haemophilus influenzae.

Nontypeable Haemophilus influenzae commonly causes infections in the lower and upper respiratory tract, although the mechanisms of its colonization and persistence in the airways are unclear. Culture filtrates from six clinical isolates of this bacterium were assessed for their abilities to influence neutrophil function in vitro. Each culture filtrate was assessed on six separate occasions with neutrophils obtained from six different donors. During the log and early stationary phases of growth (0 to 18 h), culture filtrates contained primarily neutrophil chemokinetic activity but no activity affecting neutrophil migration toward the chemotactic factors N-formyl-L-methionyl-L-leucyl-L-phenylalanine and leukotriene B4. In contrast, filtrates obtained after 24 h of culture contained factors which inhibited neutrophil migration toward both of these chemotactic factors. This chemotaxis-inhibitory activity persisted between 24 and 72 h of bacterial culture, and it was not associated with the presence of either chemotactic or chemokinetic activity as assessed by checkerboard analysis. Gel filtration of pooled 72-h filtrates yielded three major peaks of chemotaxis-inhibitory activity. Endotoxin was present together with two other low-molecular-mass hydrophobic factors of approximately 8 and 2 kDa. These low-molecular-mass factors are chloroform insoluble and heat stable, and they are inactivated by protease, periodate, and diborane reduction. Activity was completely retained on a wheat germ agglutinin column, and it could be eluted with N-acetyl-D-glucosamine. These data suggest that inhibitory activity is associated with N-acetyl-D-glucosamine-containing glycopeptides, possibly derived from the bacterial cell wall. The production of these compounds may contribute to the persistence of this bacterium in vivo by inhibiting neutrophil chemotaxis in the microenvironment of the respiratory mucosa.

Biological Factors↗

Detection and significance of bcr-abl mRNA transcripts and fusion proteins in Philadelphia-positive adult acute lymphoblastic leukemia.

Blast cells from an unselected consecutive series of 84 adults presenting with acute lymphoblastic leukemia (ALL) to St Bartholomew's Hospital over a seven year period were tested prospectively by cytogenetic and retrospectively by RT-PCR analysis for the presence of the Ph translocation and bcr-abl mRNA. This combination gave an overall figure of 20.3% for bcr-abl-positive and/or Ph-positive ALL. The incidence of bcr-abl-positive/Ph-positive ALL was most common between the ages of 31 and 50 years, becoming less common after the age of 50. Eight out of ten bcr-abl-positive patients expressed the e1a2 mRNA transcript, the other two expressed the b3a2 and b2a3 transcripts respectively. Cells from all patients with bcr-abl mRNA transcripts expressed the appropriate p190 or p210 bcr-abl protein and all were Ph-positive.

Adolescent↗

Myeloablative therapy with autologous bone marrow transplantation as consolidation of remission in patients with follicular lymphoma.

A study has been in progress since June 1985 to evaluate the use of myeloablative therapy (cyclophosphamide [60 mg/kg x 2] and total body irradiation [200 cGy x 6]) followed by reinfusion of autologous bone marrow in patients in second or subsequent remission of B-cell non-Hodgkin's lymphoma. The marrow mononuclear cell fraction is being treated in vitro with three cycles of the monoclonal antibody anti-CD20 (anti-B1, Coulter Immunology) and baby rabbit complement (Pel-Freez). Thirty-eight patients with follicular lymphoma (age range 29-61 years, median 43) have been treated to date. At the time of treatment, 28 patients were in second remission, 7 were in third, and 3 were in more than third remission. Twenty-three patients were in complete remission, 15 had residual disease (7 had lymph nodes less than 2 cm diameter, 4 had less than 10% bone marrow infiltration, 1 had involvement of lymph nodes and bone marrow, and 3 had involvement at other sites). Of the 38 study patients, 32 are alive; 6 have died, 4 in remission. Two of the deaths were treatment related: 1 resulted from cerebral haemorrhage at 29 days; 1 resulted from systemic fungal infection at three months). One patient died from secondary acute myelogenous leukaemia at four years, and another from an unrelated cause. Two patients died following relapse. The median time to engraftment was 28 days (range 15-45 days) for neutrophils greater than 0.5 x 10(9)/L and 28 days (range 15-46 days) for platelets greater than 20 x 10(9)/L.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Human macrophage colony-stimulating factor inhibits bone resorption by osteoclasts disaggregated from rat bone.

Colony stimulating factors (CSFs) regulate the survival, proliferation and differentiation of haemopoietic progenitor cells, as well as the functional activity of mature cells. Because the osteoclast is derived from haemopoietic tissue, and because osteoblastic cells produce CSFs, we tested the effects of several CSFs on bone resorption by osteoclasts disaggregated from neonatal rat long bone. We found that recombinant macrophage (M)-CSF was a potent inhibitor of bone resorption, causing significant inhibition at concentrations similar to those required to support the growth of macrophage colonies in agar. Unlike other inhibitors of osteoclastic resorption, M-CSF did not alter cytoplasmic motility in time-lapse recordings, suggesting that M-CSF may inhibit osteoclasts through a different transduction mechanism. None of the remaining cytokines tested (granulocyte-macrophage CSF, interleukin 3, interleukin 6, or interferon gamma) influenced bone resorption. M-CSF production may be a mechanism by which osteoblastic cells, which produce M-CSF, may regulate osteoclastic function. Alternatively, inhibition of osteoclastic resorption by a CSF that is responsible for amplification of the macrophage compartment may reflect a close lineage relationship between mononuclear phagocytes, in which M-CSF induces a diversion of lineage resources away from osteoclastic function.

Animals↗

Immunophenotype of blast cells in acute myeloid leukemia may be a useful predictive factor for outcome.

The immunophenotype of peripheral blood blast cells was tested in 92 patients with acute myeloid leukemia (AML), who were diagnosed and treated at single centre, St Bartholomew's Hospital, from 1978-1987 with a standard adriamycin, cytosine arabinoside and 6-thioguanine regimen. Immunological analysis involved standard fluorescence flow cytometry and utilized 31 monoclonal antibodies to known myeloid antigens (of CD groups 11b, 11c, 13, 14, 15, 16, w17, 31, w32, 33, 34, 35 and 36), a number of relatively less well studied antibodies with potential specificity for AML, and a series of control antibodies to T and B lymphocytes, platelets, erythrocytes and of widespread distribution (CD45, leucocyte common; HLA-DR). The results highlighted a number of antibodies with wide myeloid reactivity, in addition to CD13 and 33 (present in 66 per cent and 76 per cent of cases, respectively), which may be of immunodiagnostic use. A number of correlations between AML cell immunophenotype and FAB morphology subtype were found; in particular five antibodies (CD11c, 10.1, Tu3, CD15 and CD16), of both predominant granulocytic and monocytic reactivity, reacted with cells of AML-M5 subtype (p less than 0.05). There was no significant correlation between immunophenotype and clinical and pathological features at presentation. Correlation with clinical outcome was not a prominent feature, in contrast to some reports based on multicentre data. However, of particular note was the strong association between early death (at less than 2 months) and the coexpression of Leucocyte Function Associated (LFA) antigens, CD11b and 11c, on patient's blast cells (p = 0.003). The relationship was independent of clinical features and persisted even if AML-M5 cases were excluded. The significance of this latter finding is unclear, but may be related to the known role of CD11b and 11c LFA antigens in the cellular response to infection.

Adult↗

Recombinant human granulocyte macrophage colony stimulating factor following alternating non cross resistant chemotherapy in Hodgkin's disease.

Fourteen patients with Hodgkin's disease (two previously untreated, 12 following relapse or with refractory disease) were treated with a combination chemotherapy regimen comprising chlorambucil, vinblastine, procarbazine, prednisolone, etoposide, vincristine and adriamycin administered on days 1-8. Recombinant human granulocyte-macrophage colony stimulating factor (rhGM-CSF) (mammalian glycosylated, Sandoz/Schering-Plough) was administered after alternate cycles of chemotherapy from day 10 for 7 days by continuous intravenous (i.v.) infusion in 12 patients in a dose finding study (dose: 2 micrograms/kg/day in four patients, 4 micrograms/kg/day in four patients and 8 micrograms/kg/day in four patients) and by daily subcutaneous (s/c) injections in two patients (8 micrograms/kg/day). There was a rapid peripheral leucocytosis following the rhGM-CSF, reaching a peak at 1-2 days in 12/14 patients. The initial leucocytosis was composed of neutrophils followed by a rise in immature myeloid cells. There was no difference observed in the duration or depth of the nadir following chemotherapy or in the rate of recovery of peripheral white cell counts between cycles with and without rhGM-CSF in patients treated with 2 and 4 micrograms/kg/day. At the dose of 8 micrograms/kg/day, 3/6 patients had a shorter nadir duration in the cycle with rhGM-CSF, compared with cycle without rhGM-CSF. There was no difference in frequency of infection in cycles with and without rhGM-CSF. Following chemotherapy, six patients achieved clinical remission, six partial remission and two had progressive disease.

Adult↗