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Biomedical subjects

M F Greaves

Publications and source records attributed to M F Greaves.

At least 145 records · Page 8Linked to original sources

Terminal deoxynucleotidyl transferase in acute myeloid leukaemia.

Between January 1980 and May 1981, 1966 marrow or blood samples from leukaemia patients were tested for terminal deoxynucleotidyl transferase (TdT) using nuclear immunofluorescence. The cells were also tested with a panel of immunological markers including monoclonal antibodies. Of 869 TdT positive cases detected, 555 were diagnosed as ALL and 32 as blast crisis of CGL; 226 were provisionally diagnosed as 'acute leukaemia' and finally diagnosed as ALL partly on the basis of immunological data; 56 TdT+ cases were provisionally diagnosed as acute non-lymphocytic or myeloid leukaemia; 266 cases of AML and 177 cases of CGL in blast crisis were TdT negative. Eleven of the above 'AML' cases were anti-cALL+ as well as TdT+ and were re-diagnosed and treated successfully as cALL. The remaining 45 were anti-cALL negative and finally diagnosed and treated, at least initially, as AML. Eleven of these cases had only 5-10% TdT+ cells which could have been normal, non-myeloid cells. Twenty cases had 11-50% TdT+ cells and 14 cases had 50-100% TdT+ cells. Of these latter two groups, details on 28 patients were available for evaluation. Three cases on review had no definitive myeloid cytochemistry and were haematologically AUL with a null-ALL phenotype (TdT+ DR+ cALL-). In 14 cases there was a large overlap (greater than 75%) of the proportion of cells with myeloid cytochemistry (Sudan black, peroxidase or esterases) and TdT; individual blast cells were therefore expressing these markers concurrently. In the remaining cases, mixtures of TdT negative myeloid and TdT+ (lymphoid?) cells may have coexisted although this was not proven unequivocally. Twenty-two cases of newly diagnosed TdT+ 'AML' received induction chemotherapy for AML (DAT regime) and only six (37%) obtained a complete remission. It is concluded that TdT positive 'myeloid' leukaemias do occur, albeit infrequently (approx. 5%) and may have a relatively poor prognosis.

Adolescent↗

ALL masquerading as AUL.

Of 597 cases of acute leukaemia in adults (greater than 16 years) seen at St. Bartholomew's Hospital, London, between May 1973 and January 1982, 412 were diagnosed as AML, 103 as ALL and 58 as Philadelphia chromosome positive blast crisis of CML (13 presenting as acute leukaemia and 45 having a prior chronic phase). The remaining 24 cases were considered to be acute undifferentiated leukaemia. Twenty-one of the latter were investigated using a panel of immunological markers at diagnosis and/or retrospectively using frozen cell suspensions. Eighteen out of 21 were shown to have a predominantly 'lymphoid' phenotype which comprised 12 cases of common ALL (two of whom were Ph1 positive), three cases of null-ALL, one case with a probable early thymic phenotype, and two cases with a monoclonal B lymphoblast phenotype. One 'common ALL' and one 'null-ALL' had a significant proportion of pre-B (cytoplasmic mu chain+) cells. One other case reacted with anti-myeloid sera. Leukaemic blasts from two patients were unreactive with all markers tested. No cases of glycophorin positive erythroleukaemia or anti-platelet (glycoprotein I) positive leukaemia were detected. These observations suggest that the overwhelming majority of acute leukaemias have an identifiable affiliation to the lymphoid or myeloid lineages and that patients diagnosed haematologically as 'AUL' might benefit by therapy appropriate for their leukaemic cell type.

Acute Disease↗

Immunological classification of T-cell acute lymphoblastic leukaemia using monoclonal antibodies.

We had been able to classify 70 cases of acute lymphoblastic leukemia (ALL) into different immunological subtypes based on surface marker analysis with the aid of a panel of monoclonal antibodies. The relative proportions of different ALL subclasses appears to be similar to those reported from Europe and the U.S.A. Our results also indicated that monoclonal antibodies OKT11, UCHT-2 and WT1 were very useful in defining pre-T or early T subtypes of ALL. The latter leukaemias lack most maturation-linked T-cell markers but share with the other T-ALL the characteristic of low density or undetectable insulin receptors.

Antibodies, Monoclonal↗

The cellular content of non Hodgkin lymphomas: a comprehensive analysis using monoclonal antibodies and other surface marker techniques.

Five samples of tonsil, 10 reactive lymph nodes and 65 consecutive cases of non-Hodgkin lymphoma (NHL) were evaluated in suspension phenotyping with the monoclonal antibodies alpha Leu-I, alpha Leu-2a, alpha Leu-3a, OKT1, OKT3, OKT4, OKT6, OKT8, W6/32, 26/114, DA-2, 2DI, J5, AN51 and OKT9 together with conventional surface marking by rosetting (E, Fc gamma, Fc mu, C3b, C3d) and staining for surface and cytoplasmic immunoglobulin (SIg, CyIg) heavy and light chain classes. The results confirm the reproductability and specificity of staining with monoclonal antibodies against T cells and T cells subsets. Evidence is presented for reactivity of alpha Leu-I antibody with SIg positive and Ia positive cells in some lymphomas (centroblastic centrocytic, lymphocytic and immunoblastic), and 2 cases showed evidence of marking with OKT3 on SIg positive cells in T cell predominant immunoblastic lymphoma. Lymphoblastic lymphomas of T cell type expressed the marker OKT6. On the basis of these results criteria for the diagnosis of T cell lymphoma are suggested. The monoclonal antibody J5, reactive with C-ALL antigen, showed variable positivity, occasionally strong in B cells in cases of centroblastic and centrocytic follicular lymphoma. Proportions of cells staining with the monoclonal antibody OKT9 showed a correlation between levels of cellular expression of transferrin (trf) receptor and the histological grade of malignancy, OKT9+ cells being elevated in high grade lymphomas, and in some cases of transforming lymphoma of low grade histological class. These results are discussed and indicate the advantage of employing a wide range of defined monoclonal reagents in the phenotypic evaluation of NHL.

Adolescent↗

Selective expression of the common acute lymphoblastic leukemia (gp 100) antigen on immature lymphoid cells and their malignant counterparts.

The selectivity of monoclonal antibody J-5 (anti-gp 100, common ALL antigen) for normal and leukemic hemopoietic cells has been investigated. J-5 gave concordant reactions with rabbit anti-cALL, coredistributed on the cell surface, and precipitated a similar if not identical glycoprotein from leukemic and normal tissue. Normal, immature lymphoid cells reactive with J-5 were detected in bone marrow and in fetal thymus. In marrow they were largely coincident with the TdT+ population. J-5 defines a major subgroup of ALL (common ALL) with a favorable prognosis. Of 853 non-ALL acute leukemias investigated, 80 were J-5 positive. These included 14 cases diagnosed as AML, 51 TdT+ blast crises of CGL, and 15 cases diagnosed as "AUL." Of the 14 J-5+ AML, 13 were subsequently rediagnosed either as cALL (10 cases) or mixed lymphoid-myeloid leukemias (3 cases). One-hundred forty-three cases of mature lymphoid cell leukemia (91 B, 52 T) were investigated with J-5; 3 cases only, of disseminated B lymphoma, were positive, albeit weakly. A higher proportion of follicular lymphomas are, however, J-5 positive when studied in sections of biopsy material. A similar pattern of selective reactivity was observed in a series of leukemia/lymphoma cell lines. These studies emphasize the diagnostic value of monoclonal anti-cALL reagents.

Animals↗

A monoclonal antibody (WT1) for detecting leukemias of T-cell precursors (T-ALL).

The selectivity of a monoclonal anti-T antibody, designated WT1, has been assessed in a series of 906 leukemias and lymphomas. In acute lymphoblastic leukemias, WT1 reacts comprehensively and selectively with thymic acute lymphoblastic leukemia (ALL) cells in untreated or relapsed patients, thus overriding the extensive antigenic diversity of this cancer and the immaturity of the cell type involved. All 80 cases of thymic ALL examined were WT1-positive. In addition, 18 cases of presumptive prethymic ALL were also WT1-positive, but were unreactive with other maturation-linked T-cell markers. The phenotype WT1+ HLA-DR TdT+ appears to be unique to T-ALL and can therefore be used systematically for the differential diagnosis of this poor prognosis subtype of ALL. Virtually all ALL cases can now be placed into one of two major subgroups representing transformed precursors of either the T- or B-cell lineage. WT1 identifies a single polypeptide of approximately 40,000 mol wt and is similar to two previously described monoclonal antibodies.

Antibodies, Monoclonal↗

Monoclonal antiglycophorin as a probe for erythroleukemias.

A monoclonal antibody (LICR.LON.R10) specific for the major sialoglycoprotein of the erythroid cell membrane, glycophorin A (alpha), has been used to test the possibility that "cryptic" erythroleukemia may be diagnosed as acute lymphoblastic leukemia (ALL) or acute myeloblastic leukemia (AML). In addition to 27 overt erythroleukemias, 724 leukemias, including 329 ALL (103 in relapse), 205 AML, and 109 blast crises of Ph1-positive chronic myeloid leukemia, were analyzed. Twenty cases with a significant proportion of glycophorin-A-positive (gA+) cells were found; 8 of these (5 AML and 3 blast crises of chronic myeloid leukemia, CML) had an obvious erythroid component, but 12 others were diagnosed as AML (2), AMML (1), CML in myeloid blast crisis (4) or megakaryoblastic blast crisis (1), acute megakaryoblastic leukemia (2), or acute lymphoblastic leukemia (2). The latter two patients had no immunologic evidence supporting a diagnosis of ALL and were resistant to chemotherapy. We conclude that AML and ALL only very rarely express gA, and these are probably genuine "cryptic" erythroleukemias. Other gA+ leukemias (megakaryoblastic and CML blast crises) may arise from bi- or pluripotent stem cells and contain distinct and separable blast cell populations.

Antibodies, Monoclonal↗

Association of the human type C retrovirus with a subset of adult T-cell cancers.

To determine whether the human T-cell lymphoma-leukemia virus (HTLV) is associated with particular cancers, patient sera were surveyed for HTLV-specific antibodies. An association was seen with aggressive cancers of mature T-cells, specifically Japanese adult T-cell leukemia (ATL) and T-cell lymphosarcoma cell leukemia (TLCL), a similar cancer of Caribbean blacks. Ninety to 100% of these patients possessed HTLV-specific antibody. Forty-seven and 20% of relatives of ATL and TLCL patients, respectively, and 12 and 4% of healthy donors from ATL and TLCL endemic areas were also antibody positive. Visceral organ involvement, hypercalcemia, and skin manifestation, features of ATL and TLCL, were often seen in other antibody-positive patients. Childhood cancers, most cutaneous T-cell and all non-T-cell leukemias and lymphomas, myeloid leukemias, Hodgkin's disease, and solid tumors were not associated with HTLV. Healthy United States donors and European patients with non-malignant diseases were antibody negative. HTLV is thus associated with a subtype of adult T-cell leukemia-lymphoma, clustered in viral endemic areas, with apparent racial and geographic predilection.

Adult↗

Characterization of immune complexes in acute lymphoblastic leukaemia.

Sera from 120 children and young adults with acute leukaemia (59), various other tumours (53) and histiocytosis X (eight) were studied for the presence and characteristics of circulating immune complexes (CIC). Serial and parallel testing was performed using: C1q binding (solid phase), Raji cell radioimmunoassay and anti-C3 (solid phase). CIC were detected in 36 of 56 (64%) patients with acute lymphoblastic leukaemia (ALL) and in 62% of other tumour subjects. In the ALL sera, the mean positive C1q binding was 5.4 s.d., Raji cell 4.2 s.d. and anti-C3 4.4 s.d. In 12 ALL sera CIC were characterized for molecular size by sucrose gradient centrifugation. Most samples showed high molecular weight (19S) complexes but intermediate (11-14S) and smaller (8-9S) complexes were also detected. There was no apparent relationship between the presence, amount or physical size of the detectable CICs and clinical course of the patients studied; 12 patients with ALL in long term remission showed presence of CIC at some time during their course. Immune complexes precipitated from leukaemic sera were also examined for the presence of common ALL antigen (cALL) and Ia(DR) antigens utilizing rabbit antisera and mouse monoclonal antibodies. Experiments with isolated immune complexes from ALL sera provided no positive evidence for the presence of cALL antigen or Ia antigen within immune complex materials from ALL patients.

Adolescent↗

A one-step purification of membrane proteins using a high efficiency immunomatrix.

A method is described by which an immunoaffinity matrix was constructed by binding antibody directly or indirectly to protein A-Sepharose 4B followed by cross-linking of the complex with dimethyl pimelimidate. This allows optimal spatial orientation of antibodies and, thus, maximum antigen binding efficiency. The affinity matrices were stable to high and low pH buffers without any significant antibody loss. The optimal conditions of antibody saturation, cross-linker concentration, and elution system were established and affinity columns made with the monoclonal antibodies J5, W6/32, and OKT9 for one-step isolation of the common acute lymphoblastic leukemia-associated antigen, HLA-AB antigens, and transferrin receptor, respectively, from cell lysates. The same methodology was also applied to immobilize transferrin with polyvalent anti-transferrin antibodies. This was then used to isolate the transferrin receptor from cell lysates.

Antibodies, Monoclonal↗

Human Thy-1: expression on the cell surface of neuronal and glial cells.

The Thy-1 antigen is a cell surface glycoprotein found in neural tissue of all mammalian species so far studied. The distribution and amount of this antigen has been measured on 4 human neuronal and 2 neuroglial cell lines and on fresh tumour cells of neuronal origin. In 3 out of 4 neuronal lines (LAN-1, TR14, CHP 212) more than 90% of cells were Thy-1+, however, LAN-1 cells showed only weak immunofluorescence and bore on average 2.4 times fewer molecules of Thy-1 per cell than those of either TR14 or CHP 212. The mean number of Thy-1 molecules per TR14 cell was shown to be approximately 2.25 x 10(5). In contrast, only 66% of cells in the fourth neuronal line (CHP 100) were Thy-1+, although these showed strong immunofluorescence. Both glial cell lines, UCH-203 and H314/123, showed strong Thy-1 immunofluorescence on more than 90% of cells. Similarly, with fresh neuronal tumour cells, although approximately 80% of tumours were Thy-1+ (essentially 100% of cells in these being positive) there were considerable differences in the intensity of labelling by immunofluorescence between different tumours. Such heterogeneity in cell lines and malignancy may reflect normal in vivo variation. Different phenotypes might therefore represent separate neural cell lineages, or simply differences in maturational status within a lineage. The very low frequency of Thy-1+ cells in normal bone marrow (less than 0.1% of nucleated cells) indicates that anti-Thy-1 antibodies may be valuable in both the diagnosis and subsequent treatment of neuroblastoma.

Antigens, Neoplasm↗

Adult T-cell lymphoma-leukaemia in Blacks from the West Indies.

Six Black patients (five born in the West Indies and one in Guyana), aged 21-55 years, had adult T-cell lymphoma-leukaemia diagnosed in the U.K. This disorder is rare in Europe and the U.S.A., but is more common in Japan. Five patients had severe hypercalcaemia which correlated with disease activity, although osteolytic lesions were found in only one. Other clinical features were lymphadenopathy and a high white blood-cell count (range 27-67 X 10(9)/l) with a predominance of pleomorphic lymphoid cells with pronounced nuclear irregularities prominent at ultrastructural level. The cells in all cases formed rosettes with sheep red blood-cells and lacked terminal transferase. Analysis with OKT monoclonal antibodies in four cases confirmed a mature T-cell phenotype defined as helper/inducer (T4+, T6-, T8-) in three. Combination chemotherapy resulted in short-lived remissions; four patients died and two have survived 3-6 months. The disease in these patients is indistinguishable on clinical and pathological grounds from adult T-cell leukaemia/lymphoma in Japan. Geographical clustering among certain racial groups suggests common aetiological factors in the pathogenesis of this disease. The finding of high titre antibody against the structural core protein (p24) of a new human C-type leukaemia virus (human T-cell leukaemia/lymphoma virus) in all tested cases from this series and data from all but one case from Japan suggest that one such factor may be viral.

Adult↗

Biochemical characterisation of leukaemia-associated antigen p24 defined by the monoclonal antibody BA-2.

The leukaemia-associated cell surface antigen p24/BA-2 is a single polypeptide chain with a molecular weight of 24,000. Treatment with glycosidases or exposure of cells to tunicamycin failed to show any change in the molecular weight of the antigen when examined by SDS-polyacrylamide gel electrophoresis. In addition, it failed to bind to lectin affinity columns of concanavalin A, lentil lectin or ricinus communis lectin. This is consistent with the absence of N-asparagine linked oligosaccharide chains on the antigen. Pulse-chase labelling of protein p24 shows a post-translational modification resulting in a molecular weight increase of approx. 500-1000. Alkaline treatment resulted in a decrease in molecular weight of approximately the same amount, suggesting that p24 contain some O-glycosidically linked oligosaccharide. Protein p24 has a basic pI of 7.3 which is unchanged after neuraminidase treatment. Protein P24/Ba-2 cannot be labelled by either the lipophilic photoactivatable nitrene reagent, hexanoyldiiodo-N-(4-azido-2-nitrophenyl)tyramine, or with [32P]phosphate. This suggests that the molecule is non-integral in nature and that it does not form an intimate association with the lipid matrix. Identical molecular weights, when reduced and non-reduced antigens were compared, suggest that it contains no internal disulphide linkages and failure to detect any other band on gradient gel SDS-polyacrylamide gel electrophoresis from 5-15% suggests that is is not strongly associated with any other structure.

Animals↗

Modulation of T leukaemic cell phenotype with phorbol ester.

A panel of monoclonal antibodies and other markers (e.g., terminal deoxynucleotidyl transferase, sheep erythrocyte rosettes, peanut agglutinin) have been used in conjunction with flow cytometry and biochemical analysis to monitor the induction of maturation in human thymic (T) leukaemic cell lines by phorbol ester (TPA). Seven cell lines underwent multiple phenotypic alterations in response to TPA but were unresponsive to synthetic thymic hormones (TP5, FTS) or to other compounds (e.g. DMSO, retinoic acid) which induce maturation in other types of leukaemia. The changes parallel those observed in normal T-cell differentiation and partly reflect alterations in glycosyl transferase activity, altered synthesis of proteins and regulation of cell surface receptors (for transferrin) associated with rapid growth and metabolism. These studies further illustrate the reversibility of maturation arrest in human leukaemia and provide support for the view that leukaemia may involve regulatory defects in the coupling of proliferation and maturation. Induction of promotion of terminal differentiation in leukaemic equivalents of T-cell precursors may provide a convenient system for the study of biochemical and molecular events involved in T-cell development and diversification.

Antibodies, Monoclonal↗

Monoclonal antibodies OKT 11 and OKT 11A have pan-T reactivity and block sheep erythrocyte "receptors".

Monoclonal antibodies OKT11 (gamma 1) and OKT11A (gamma 2) are described and appear to have similar binding specificities. They bind, in immunofluorescence, with greater than 95% of infant thymocytes, staining both cortical and medullary cells, 65-80% of blood lymphocytes and selectively stain the T cell-dependent paracortical areas of tonsil. A small proportion (9-12%) of bone marrow lymphocytes stain, but this population excludes the terminal transferase-positive cells. Both the gamma 1 and gamma 2 antibodies stain the surface membrane Ig-negative lymphocytes in blood and tonsil and are to block sheep E rosette formation (to normal or leukemic T cells). In contrast, other monoclonal anti-T reagents tested (OKT1, OKT3, OKT4, OKT6, OKT8, OKT9, OKT10) did not block E rosette formation. E rosette formation and OKT11 bindings are coincident on T-ALL cell lines and both are trypsin-sensitive. In a series of 145 leukemias and 26 leukemic cell lines investigated, only leukemias with a T cell phenotype including E rosette positivity were reactive with OKT11 and OKT11A. OKT11A binds to a polypeptide of approximately 50 000 molecular weight on thymic lymphocytes. This structure may carry the recognition site for sheep erythrocytes. These antibodies provide additional useful markers for T cell analysis and are of potential therapeutic value.

Animals↗

"Target" cells, cellular phenotypes, and lineage fidelity in human leukaemia.

A detailed analysis of lymphoid leukaemia cells with a panel of monoclonal antibodies plus other markers indicates a striking conservation of phenotype that closely mimics that of normal lymphoid precursor or progenitor cells and reflects the imposition of maturation arrest. The composite phenotypes detected show some minimal deviations or asynchronies (with respect to maturation "stages") but are faithful with respect to cell lineage. These observations are suggested to shed light on the available "target" populations for lymphoid malignancy in humans and challenge the view that dedifferentiation or qualitatively aberrant gene expression is common and important in malignancy. They are further taken to support the view that normal gene products that regulate or couple proliferation and maturation are critically involved in the successive clonal selection events underlying the evolution of leukaemia. No qualitatively unique and consistent leukaemia "markers" may exist or be required. The only exception to this rule are the nonrandom chromosome changes, which, it is suggested, involve genetic loci critical to the regulation of growth and maturation in particular normal cell types.

Antibodies, Monoclonal↗