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J A Child

Publications and source records attributed to J A Child.

At least 55 records · Page 3Linked to original sources
PubMed1994

ChlVPP/PABlOE and radiotherapy in advanced Hodgkin's disease. The Central Lymphoma Group.

PURPOSE: The United Kingdom Central Lymphoma Group (CLG) has modified mechlorethamine, vincristine, procarbazine, and prednisone/doxorubicin, bleomycin, vinblastine, and dacarbazine (MOPP/ABVD) by substituting mechlorethamine with chlorambucil and dacarbazine with etoposide in the treatment of patients with advanced Hodgkin's disease (HD). Prednisolone is included in the bleomycin-containing combination, and the vinca alkaloids have been switched to balance the myelotoxicity of the two component regimens. PATIENTS AND METHODS: The resulting ChlVPP/PABlOE regimen is as follows: on days 1 to 14, chlorambucil 6 mg/m2 orally, procarbazine 100 mg/m2 orally, and prednisolone 30 mg/m2 orally; on days 1 and 8, vinblastine 6 mg/m2 intravenously (i.v.); on day 29, doxorubicin 40 mg/m2 i.v.; on days 29 and 36, vincristine 1.4 mg/m2 (maximum, 2 mg) i.v., and bleomycin 10 mg/m2 i.v.; on days 30, 31, and 32, etoposide 200 mg/m2/d orally; on days 29 to 43, inclusive, prednisolone, 30 mg/m2 orally. The second full cycle restarts on day 50. Treatment continues to maximum response plus two full cycles, but with a minimum of three full cycles. Radiotherapy is administered, after chemotherapy, to sites of previously bulky disease. Since 1983, 216 patients with previously untreated, advanced Hodgkin's disease (HD) have entered this study. RESULTS: The complete remission (CR) rate after chemotherapy was 73% (95% confidence interval [CI], 67% to 79%), and after additional radiotherapy was 85% (95% CI, 80% to 90%). The failure-free survival (FFS) rate at 5 years was 68% (95% CI, 61% to 74%), and the overall actuarial survival at 5 years was 78% (95% CI, 72% to 84%). The CR rate in patients in the poorer prognostic categories was high: 81% in patients with albumin levels less than 37 g/L, 79% in patients older than 40 years of age, 84% in stages IIIB plus i.v. disease, and 79% in patients presenting with B symptoms. As expected, nausea and vomiting were not major problems, although infection, often in the context of myelosuppression, complicated almost half the cases, and 29% of patients required admission at some stage for treatment of infection. CONCLUSION: In this multicenter study, ChlVPP/PABlOE produced results comparable to those reported for MOPP/ABVD, but with less nausea and vomiting. Treatment duration was shorter than in the original MOPP/ABVD regimen, and than that used in the Cancer and Leukemia Group B (CALGB) trial. It will now be compared with PABlOE alone.

Adult↗
PubMed1993

Transient and persistent expansions of large granular lymphocytes (LGL) and NK-associated (NKa) cells: the Yorkshire Leukaemia Group Study.

A survey of 870 different adult blood samples (primarily from patients with non-haematological disorders) found that 269 (31%) had increased proportions (> 25%) and/or absolute numbers (> 1.0 x 10(9)/l) of morphologically-defined large granular lymphocytes (LGL), and/or phenotypically-defined NK-associated (NKa) cells. Of these, 112 were re-analysed at least 6 months after initial presentation and were classified as 'persistent' (92/112) or 'transient' (20/112) according to whether or not the original abnormality was still present. Lymphocyte counts in most patients with persistent abnormalities were within normal limits (18/92) or slightly increased (68/92), with only six having a lymphocytosis exceeding 10.0 x 10(9)/l. With the exception of five persistent LGL expansions in which the granular lymphocytes did not express NKa determinants (designated LGL+NKa-), the remaining 87 cases could be phenotypically grouped according to their primary abnormality as CD8+NKa+ (n = 33), CD4+ NKa+ (n = 14), CD8dim+NKa+ (n = 7) or CD8-NKa+ (n = 33). TCR genotypic studies in 58 patients showed that the 16 patients with rearranged TCR components were restricted to the CD8+NKa+ group and that, in most of these, the CD8+ fraction showed abnormal relative CD16/CD56 expression. Persistent neutropenia (n = 15) also appeared to be associated with primary abnormalities of CD8+NKa+ cells (12/15), with 10 of these additionally showing rearranged TCR genes. In contrast, persistently increased CD8dim+NKa+ and CD8-NKa+ components did not appear to phenotypically differ from their corresponding 'counterparts' in normal bloods or in patients with transient LGL/NKa+ abnormalities. This survey has therefore established that persistent LGL/NKa+ abnormalities are considerably more common than suggested in published work, that a high proportion of patients with expanded CD8+NKa+ components, with quite diverse clinical histories, show evidence of clonal lymphoid populations, and that the clonal nature of such disorders appears to be associated with abnormal NKa phenotypic patterns.

Adult↗
PubMed1991

The MHC class I associated beta 2-microglobulin (beta 2m) light chain is expressed in a molar excess over HLA-ABC and CD1 on the membrane of leukaemic B cells but not leukaemic T cells: evidence for further beta 2m-associated molecules.

Beta 2-microglobulin (beta 2m) constitutes the common light chain of both the MHC-encoded HLA-ABC molecules and a group of structurally related glycoproteins recognized by antibodies of the first cluster of differentiation (CD1a, CD1b and CD1c). These CD1 antigens appear similar to murine T1 and Qa molecules in terms of structure and tissue distribution, although the question of inter-species homology is controversial. A further group of alloantigens expressed predominantly on T cells has been reported however, with immunogenetic characteristics more closely analogous to the murine T1/Qa system than the CD1 antigens, although their precise identity remains ill-defined. Having previously shown that malignant B cells may express membrane CD1c, we examined leukaemic B-cells corresponding to early lymphoblastic differentiation (null- and common acute lymphoblastic leukaemia) through to the terminal plasma cell stage for the expression of other non-HLA class I beta 2m-associated molecules. It was found that leukaemic B-cells at intermediate/late stages of differentiation, represented by non-Hodgkin's lymphoma (B-NHL) and 'hairy-cell' leukaemia (HCL), had significantly higher beta 2m:HLA-ABC ratios than did the cells from other types of B-cell malignancy. Although leukaemic B cells with a demonstrable non HLA-ABC-associated beta 2m component expressed detectable levels of CD1c, and insignificant levels of CD1a and CD1b, the antigen density was insufficient to account for the excess beta 2m. In vitro stimulation of leukaemic B cells by phorbol ester substantially increased the expression of HLA-ABC and CD1c, but also accentuated further the difference between the expression of these molecules and that of beta 2m. There was no detectable beta 2m other than that associated with HLA-ABC and CD1 on the surface of malignant T cells by contrast. Our findings strongly support the existence, at certain stages of leukaemic B-cell differentiation, of an additional beta 2m component(s) other than that associated with HLA-ABC and CD1.

Antigens, CD↗
PubMed1990

In vitro beta 2-microglobulin (beta 2m) secretion by normal and leukaemic B-cells: effects of recombinant cytokines and evidence for a differential response to the combined stimulus of phorbol ester and calcium ionophore.

Due to the increasing therapeutic use of immunoregulatory agents and the potential effects on cellular function, we examined the modulation of in vitro beta 2-microglobulin (beta 2m) production rates by 'normal' tonsil and leukaemic B-cells in response to a number of these agents. Tonsil B-cells responded to phorbol ester (TPA) by an increased beta 2m production rate, which was further enhanced by the combined stimuli of TPA plus the calcium ionophore A23187. In marked contrast, however, lymphocytes from a majority (8/11) of B-cell malignancies showed a suppression of the TPA-induced beta 2m production rate in response to the combined TPA/A23187 stimulus. These different responses of 'normal' and malignant B-cells were not apparent when IgM production rates were examined. The recombinant cytokines IL-1, IL-2, IFN-alpha, IFN-gamma and TNF also enhanced beta 2m production rates of both normal and leukaemic B-cells, but to a considerably lesser extent than did TPA. Bryostatin-1 increased beta 2m production to a level intermediate between that obtained by TPA and the cytokines. It is suggested that beta 2m production rates may correspond to the degree of B-cell differentiation, and/or to the degree of cellular 'activation'. The results further indicate that the in vitro measurement of beta 2m production provides a different index of the cellular response than that obtained by the conventional measurement of IgM production.

Adjuvants, Immunologic↗
PubMed1990

Phenotypic switch from CD45RA+ to CD45RA- by normal blood T cells is associated with increased HLA-ABC expression for CD4+ and CD8+ populations but not for the NK-associated CD4-CD8dim+ or CD4-CD8- fractions.

Using the combined techniques of immunomagnetic depletion and multiple colour flow cytometry, the expression of HLA-ABC (W6/32) by normal T-cell subpopulations, defined by 2H4 (CD45RA) expression, was examined. It is thought that a CD45RA+CD45RO- phenotype defines the 'virgin' T-cell fraction, whereas a CD45RA-CD45RO+ phenotype defines the 'primed' or memory T-cell population. In addition, an intermediate phenotype (CD45RA+CD45RO+) appears to correspond to a transitional stage of development. In this study, these three phenotypic stages were represented by distinct levels of 2H4 staining defined as 2H4+, 2H4int and 2H4-, respectively. The results of this current investigation are of importance in two main areas. Firstly, when compared to the 2H4+ component, the HLA-ABC expression of 2H4- cells was significantly higher. This was true for both CD4+CD8- and CD4-CD8+ lymphocytes, but was not the case for CD4-CD8dim+, CD3+CD4-CD8- and CD3-CD4-CD8- fractions. Additionally, when HLA-ABC expression was examined as a function of 2H4 staining intensity, it was found that, for the CD4+ fraction, the greatest increase in HLA-ABC expression occurred between the 2H4int and 2H4- stages. In contrast, the increase in HLA-ABC expression by CD8+ lymphocytes was associated with transition from 2H4+ to 2H4int status, which suggests that increased HLA-ABC expression occurs at an earlier stage in the acquisition of CD45RO in CD8+ cells than for CD4+ cells. Secondly, for each individual blood examined, a close and highly significant correlation (P = 0.002) for membrane HLA-ABC expression was found between (i) CD4+2H4+ and CD8+2H4+ and (ii) CD4+2H4- and CD8+2H4- subpopulations. This suggests that modulation of HLA-ABC expression in CD4+ and CD8+ cells is subject to common control mechanisms and remains proportionate for these lymphocyte fractions in any given individual.

Antigens, CD↗
PubMed1989

Diagnostic differentiation of chronic B-cell malignancies using monoclonal antibody L161 (CD1c).

The expression of membrane CD1c, as defined by monoclonal antibody L161, was examined on malignant lymphoid cells from 191 cases of chronic lymphoproliferative disease and on eight 'normal' enriched tonsil B-cell extracts. Of 79 cases of chronic lymphocytic leukaemia (CLL) studied, 77 showed low (less than 20% positive cells) CD1c expression whereas 63/71 (89%) cases of B-PLL, HCL and B-NHL showed increased CD1c+ (but not CD1a or CD1b) components. In contrast, malignancies corresponding to terminal stages of B-cell differentiation (immunocytoma and myeloma) generally showed low CD1c expression as did lymphoid cells from 10 cases of post-thymic malignancy. Although there was some correlation between the expression of membrane CD1c and immunoglobulin (SIg) light chain densities (P less than 0.001), it is relevant in diagnostic terms that seven cases of B-NHL with low SIg staining intensities more typically associated with CLL were CD1c+. CD1c expression was not, however, correlated with the presence of CD23 or FMC7 determinants but did show a similar pattern of expression to that previously reported for beta-2 microglobulin. Determination of cellular CD1c by APAAP immunocytochemistry confirmed the presence of higher antigen densities in malignant B-cells at intermediate/late stages of differentiation and this interpretation was further supported by the finding that the majority of phenotypically mature tonsil B-cells were also CD1c+. The determination of CD1c expression by malignant B-cells may therefore be of particular value in the diagnostic differentiation of chronic lymphoproliferative disorders.

Antibodies, Monoclonal↗
PubMed1988

A new approach to the treatment of advanced high-grade non-Hodgkin's lymphoma--intensive two-phase chemotherapy.

A total of 110 patients with high-grade non-Hodgkin's lymphoma (NHL) not previously treated by chemotherapy or by radiotherapy at more than one site of disease underwent a regimen comprising an intensive 6-week initial, induction phase using vincristine, adriamycin, methotrexate, and prednisolone (VAMP) followed by the non-cross-resistant combination cyclophosphamide, etoposide, and vindesine (EEE). The median age of patients was 54 years, the majority having stage IV disease. The median follow-up was 34 months and all patients have completed treatment. The overall complete remission (CR) rate for all patients was 68%. The initial phase of treatment produced a CR rate of 49%. The full regimen was completed by 87 patients, and of these, 66 (76%) achieved CR. Of those achieving CR, 72% were relapse-free, on an actuarial basis, at 2 years. Overall 2-year survival was 53%, with a median survival of 31 months. The survival of older patients and those with lymphoblastic histology was comparable to that of other groups. The survival prospects of patients with stage IV disease was not as good as that of other patients, with a significant trend to shorter survival in patients with more advanced disease. Toxicity was predictable and manageable for both phases of the regimen, although it was more severe for the initial phase. Dose-limiting toxicities were neutropenia and mucositis. This regimen is active in the treatment of advanced high-grade NHL with acceptable toxicity. These results have encouraged us to continue the study of weekly chemotherapy, which we will compare with standard cyclical chemotherapy in a prospective, randomized trial.

Adolescent↗
PubMed1988

Expression of MHC class I and class I-like gene products on the cell membrane of mature and immature T cells.

Beta 2-microglobulin (beta 2m) constitutes the 12 kD light chain of the MHC-encoded 43-kD glycoprotein HLA-ABC molecules, which are expressed on most nucleated cells. The T6 (CD1a) antigen is expressed on thymocytes in reciprocal manner to HLA-ABC, having a similar structure to the HLA-ABC molecule. We have determined the expression of beta 2m, HLA-ABC and the T6 antigen on the cell-surface of CD1a+ and CD1a- thymocytes (defined by NA1/34 expression), and have shown that despite immunophenotypic differences between these two stages of thymic maturation, the quantity of beta 2m-associated molecules expressed was not significantly different. The nature of the heavy (alpha) chain associated with beta 2m, however, differed since HLA-ABC had largely replaced T6 on the surface of CD1a- thymocytes. We also determined the expression of beta 2m and HLA-ABC on the surface of peripheral blood CD4+ and CD8+ T-cells, and showed that the CD8+ population expressed higher levels of these antigens than CD4+ T-cells, with no detectable excess beta 2m over HLA-ABC for either subpopulation. In addition, thymocytes expressed fewer beta 2m-associated determinants than peripheral blood T-cells. These results indicate an increase in the expression of beta 2m-associated molecules with differentiation from thymic to peripheral T-cell, with a further increase in such molecules expressed on the CD8+ compared to the CD4+ peripheral T-cell subpopulation.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1988

Acne vulgaris and malignancy.

Seventy patients with lymphomas and leukaemias were interviewed. Details of past acne vulgaris were recorded and a clinical examination performed. A history of acne was less common in the patients than in matched controls. In addition, fewer patients had received treatment prescribed by a medical practitioner for their acne than had the controls. Examination revealed fewer patients with acne. These results suggest a reduced incidence of acne or its more severe forms in patients who have developed lymphomas and leukemias, and provide some support for the hypothesis that increased exposure or response to P. acnes, as appears to occur with acne, could confer protection against malignant disease.

Acne Vulgaris↗
PubMed1988

Prognostic indicators in centroblastic-centrocytic lymphoma.

The prognostic importance of ploidy and proliferative index (%S + G2) assessed by flow cytometry, mitotic and centroblast counts, and histological growth pattern were evaluated in biopsy specimens taken before treatment from 60 cases of centroblastic-centrocytic non-Hodgkin's lymphoma. Cases with a high proliferative index (greater than or equal to 18%) or DNA aneuploidy showed significantly poorer survival than those with a low proliferative index (less than 18%). A high mitotic count was also associated with a poor prognosis. On multiple regression analysis the flow cytometric assessments and mitotic counts were significant predictors of survival. Assessments of proliferative activity clearly have prognostic potential in centroblastic-centrocytic lymphoma and may permit more accurate characterisation of individual tumours.

Adult↗
PubMed1988

MHC class I and class I-like gene product expression by malignant T cells: relationships between CD1a, HLA-ABC and beta 2-microglobulin.

Beta 2-microglobulin (beta 2m) forms the invariant light chain of the MHC-encoded HLA-ABC and the non-MHC-encoded CD1 molecules. While HLA-ABC (MHC Class I) molecules are virtually ubiquitous in tissue distribution, CD1 determinants by contrast are more restricted. We have assessed, by indirect immunoenzymeassay, the relative membrane densities of these molecules on malignant thymic and post-thymic T cells. It was found that the T cells of mature post-thymic proliferations expressed significantly more beta 2m-associated protein, predominantly HLA-ABC in nature, than thymic-ALL blasts. This parallels the situation found in normal peripheral T cells and thymocytes. In contrast to post-thymic T cells, thymic-ALL blasts showed considerable case to case variation with respect to non-HLA-associated beta 2m and, of particular interest, not all of this excess beta 2m could be accounted for by CD1a. We therefore conclude that other beta 2m-containing molecules may be expressed on thymic-ALL blasts and possibly also on post-thymic leukaemic T cells. In addition, it was found that T cells from CD4+ cases of post-thymic proliferations expressed more beta 2m-associated determinants than other T cells, whether of either normal or malignant origin, and that certain post-thymic malignancies express significantly increased levels of beta 2m-associated protein relative to normal peripheral T-cells. This is in direct contrast to the situation seen in many solid malignancies.

Antigens, Differentiation↗