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Biomedical subjects

E Matutes

Publications and source records attributed to E Matutes.

At least 235 records · Page 13Linked to original sources

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↗

A novel human macrophage-activating factor: distinction from interferon-gamma (IFN-gamma) and granulocyte-macrophage colony-stimulating factor (GMCSF).

Culture supernatant from a human T-cell leukemia virus type I (HTLV-1)-infected cell line, DGA-1, contained a novel macrophage-activating factor (MAF). This MAF was antigenically and functionally distinct from interferon-gamma (IFN-gamma) and from granulocyte-monocyte colony-stimulating factor (GMCSF). Potential contaminants such as bacterial lipopolysaccharide (LPS), Mycoplasma spp, and HTLV-1 were not responsible for this MAF activity. The DGA-1 MAF was secreted constitutively and the cell line grew well in the absence of growth factors such as interleukin-2, mitogen, or antigen. This cell line should provide a good source of this MAF for further purification and characterization.

Animals↗

HTLV-1 infection in tropical spastic paraparesis: lymphocyte culture and serologic response.

All 17 patients with tropical spastic paraparesis (TSP) in a series seen in the United Kingdom have antibodies to the human T cell leukemia virus type 1 (HTLV-1). Cultured peripheral blood lymphocytes from these patients formed multinucleated giant cells and reacted with sera and monoclonal antibodies to HTLV-1 in a manner identical to adult T cell leukemia-lymphoma (ATLL) patient lymphocytes. Western blot analysis failed to reveal any marked difference in the antigens recognized by sera from TSP and ATLL patients. The sera from TSP patients, their asymptomatic relatives and ATLL patients were titrated using the following assays: enzyme-linked immunosorbent assays (ELISA), particle agglutination, antibody-dependent cell-mediated cytotoxicity, and pseudotype neutralization. There were significantly stronger serologic responses in the TSP patients than in their relatives or ATLL patients. High antibody titers in the presence of replicating virus often reflect the antigen load; however, these data are also consistent with the suggestion that neurologic damage in TSP may be immunologically mediated.

Adult↗

Polyclonal integration of HTLV-I proviral DNA in lymphocytes from HTLV-I seropositive individuals: an intermediate state between the healthy carrier state and smouldering ATL.

We have studied 15 individuals (aged 14-74 years) with antibodies to HTLV-I in their serum and random integration of HTLV-I proviral DNA in their peripheral blood lymphocytes. All but one of these patients suffered from a variety of non-specific complaints which did not correspond to those of adult T-cell leukemia (ATL). All of them were born in Kyushu and Okinawa which are endemic areas for HTLV-I infection; 25% of their family members were also seropositive for HTLV-I. The only haematological abnormality in these patients was the presence of few atypical lymphoid cells in the peripheral blood. The CD4/CD8 ratios were normal but the proportion of Tac positive cells was slightly higher than normal. These individuals with polyclonal integration of HTLV-I proviral DNA seem to represent an intermediate state between smouldering ATL (monoclonal integration) and healthy HTLV-I carriers (with antibodies but no detectable HTLV-I proviral DNA). Patients with this intermediate state of HTLV-I infection may be at risk to progress to ATL. The natural history of HTLV-I infection in humans leading to the development of ATL is reviewed in the light of these new findings.

Adolescent↗

The role of ultrastructural cytochemistry and monoclonal antibodies in clarifying the nature of undifferentiated cells in acute leukaemia.

The nature of the cells in 21 cases of acute leukaemia with blasts which were undifferentiated by light microscopy criteria was investigated by immunophenotyping, ultrastructural cytochemistry and DNA analysis. Two groups of cases were recognized. Fourteen cases were negative with B and T lymphoid markers and expressed one or two myeloid antigens detected by the monoclonal antibodies (McAb) MCS2 (CD13) and MY9 (CD33). Peroxidase activity was demonstrated at ultrastructural level by the method of Roels on unfixed cells in eight out of 10 cases; rearrangement of the immunoglobulin (Ig) genes was demonstrated in one of the three cases investigated. These cases are proliferations of early, MO, myeloblasts which can only be recognized by immunological and ultrastructural cytochemical methods. The remaining seven cases revealed a complex phenotype with expression of myeloid and lymphoid antigens. Peroxidase activity was detected in blasts from two cases with rearrangement of the Ig-heavy chain gene; in one of them the T cell receptor beta and gamma chain genes were also found in rearranged configuration. This group comprises cases of biphenotypic and mixed acute leukaemia which probably involve multipotent stem cells. This study demonstrates that the expression of myeloid antigens on blast cells parallels closely the presence of peroxidase activity and that lymphoid markers correlate with gene rearrangements at DNA level. Our findings are reassuring with respect to the specificity of the antimyeloid McAb for the diagnosis of cases which are unclassifiable by conventional methods.

Acute Disease↗

Terminal deoxynucleotidyl transferase positive acute myeloid leukaemia: an association with immature myeloblastic leukaemia.

The morphology, membrane markers and ultrastructural cytochemistry of 39 cases of acute myeloid leukaemia (AML) with variable proportion (10-99%) of terminal deoxynucleotidyl transferase (TdT) positive blasts was compared with that of 134 cases of TdT negative AML. The incidence of TdT positive AML was 22.5% and this was significantly higher in poorly differentiated myeloblastic (M0 and M1) types (54%) than in all other FAB subtypes (10%; P less than 0.001). Our findings suggest heterogeneity among TdT positive cases. Whilst the majority correspond to genuine TdT positive AML in which evidence for exclusive myeloid nature was demonstrated by phenotypic, cytochemical and ultrastructural markers, a distinct minority (22%) of cases had mixtures of lymphoid and myeloid blasts. A change in phenotype occurred in three out of six cases studied in relapse. There was no difference in the incidence of immunoglobulin (Ig) gene rearrangement between TdT positive (two out of 12) and TdT negative (one out of 11) cases, although published data suggests that Ig gene rearrangement is significantly more common in TdT positive cases. The determination of TdT in AML allows the identification of cases of mixed acute leukaemia which probably represent proliferations of multipotent progenitor cells. The majority of TdT positive cases, nevertheless, correspond to immature types of myeloblastic leukaemia which may constitute a clinically distinct subgroup.

Adult↗

Comparison of immunoperoxidase staining with indirect immunofluorescence, ELISA, and Western blotting assays for detecting anti-HTLV-I antibodies in systemic lupus erythematosus.

Serum antibodies against human T cell leukaemia virus type I (HTLV-I) were investigated in 12 patients by four methods: indirect immunoperoxidase staining, indirect immunofluorescence, enzyme linked immunosorbent assay (ELISA), and strip radioimmunoassay based on the Western blotting assay. Seven patients had systemic lupus erythematosus (SLE) and five various autoimmune diseases with one or more circulating autoantibodies. Serum samples from three patients were found to be HTLV-I-positive by the ELISA assay and sera from five patients showed a non-specific reaction by indirect immunofluorescence. These sera were negative when tested by indirect immunoperoxidase staining and Western blotting assay. All four methods gave positive results when tested with samples from 19 HTLV-I carriers and 16 patients with adult T cell leukaemia. Indirect immunoperoxidase staining and Western blotting assay are probably useful and more specific assays for the detection of anti-HTLV-I antibodies in samples from patients with autoimmune diseases.

Adult↗

Early expression of MCS2 (CD13) in the cytoplasm of blast cells from acute myeloid leukaemia.

The expression of two myeloid antigens identified by the monoclonal antibodies (McAb) MCS2 (CD13) and MY9 (CD33) was investigated in 136 cases of leukaemia. MCS2 was positive in blast cells of 78 of 88 (88.5%) and MY9 in 51 of 81 (64%) cases of acute myeloid leukaemia (AML) and chronic granulocytic leukaemia in myeloid blast crisis. One or other McAb, or both, were positive in all but 2 (2.3%) of these cases. MCS2 was more sensitive than MY9 to detect blasts of the myeloid lineage due to its most frequent reactivity in the cytoplasm of fixed cells by the immunoperoxidase (IP) technique compared with its membrane expression on cell suspensions by immunofluorescence (IF). MY9 was not suitable for tests on fixed cells. MCS2 was positive by IP but not by IF in 24% of AML, but the reverse was not observed. This suggests that the antigen detected by MCS2 is expressed in myeloblasts first in the cytoplasm and later on the cell membrane, pattern which is similar to that of the early antigens CD3 and CD22 in T and B lineage lymphoblasts, respectively. MCS2 was always positive in FAB types of AML-involving myeloblasts (M1-M4), including cases of undifferentiated morphology (M0), whilst MY9 was more frequently positive in monocytic leukaemia (M5). On the other hand, MCS2 was positive in 4 of 33 cases of acute lymphoblastic leukaemia and MY9 in 1. We conclude that both McAb, particularly MCS2, contribute to the better characterisation of myeloid leukaemias but that other tests are required to clarify the nature of the blasts when unexpected reactivities are observed.

Antibodies, Monoclonal↗

T-cell leukemias with rearrangement of the gamma but not beta T-cell receptor genes.

beta and gamma T cell receptor (TCR) gene configuration was studied in 12 patients with large granular lymphocyte T cell leukemia (LGL-leukemia). Both genes were found rearranged in ten cases. In the remaining two patients TCR beta was found in germline configuration. In one of them rearrangement of T cell-rearranging gene gamma (TRG gamma) and a gamma mRNA were demonstrated. We suggest that in this patient the leukemic T cells arose from one of the rare T cells bearing a gamma-delta rather than an alpha-beta TCR heterodimeric molecule. In the other patient several discrete TRG gamma rearrangements were detected. Because her leukemic cells were shown to be monoclonal on the grounds of their karyotype, we suggest that her leukemia originated before any rearrangement had taken place. The combined use of TCR beta and TRG gamma probes provides new information on the origin and clonal expansion of lymphoid cells in LGL-leukemia.

Antigens, Differentiation↗

T-cell chronic lymphocytic leukaemia: the spectrum of mature T-cell disorders.

Mature (post-thymic) T-cell malignancies comprise a heterogeneous group of diseases with distinct clinical, morphological and immunophenotypic features. As some of these features overlap in the various disorders, it is essential to use a number of diagnostic criteria to define the clinicopathological entities, namely: membrane markers, morphology by light and electron microscopy, clinical features, seroepidemiology of HTLV-I, histopathology, cytogenetic studies and DNA analysis. The latter, which is necessary to document clonality and confirm T-lineage, examines the rearrangement of the T-cell receptor beta, gamma and delta genes. By means of this multiparameter approach, it is possible to distinguish within the post-thymic leukaemias 4 disease entities: T-chronic lymphocytic leukaemia or large granular lymphocyte leukaemia, T-prolymphocytic leukaemia, adult T-cell leukaemia/lymphoma and Sézary syndrome.

Cell Differentiation↗

Membrane phenotype and response to deoxycoformycin in mature T cell malignancies.

The adenosine deaminase inhibitor deoxycoformycin was used in low doses to treat 19 patients with clinically aggressive T cell malignancy with a mature membrane phenotype. The patients comprised eight with prolymphocytic leukaemia, two with chronic lymphocytic leukaemia, four with adult T cell leukaemia-lymphoma, three with Sézary syndrome, and two with T cell lymphoma. Two thirds of the patients had been resistant or minimally responsive to combination chemotherapy. Complete remission was obtained in five patients (two with prolymphocytic leukaemia and one each with chronic lymphocytic leukaemia, adult T cell leukaemia-lymphoma, and Sézary syndrome) and partial remission in two others. Unmaintained complete remission lasting more than one year was seen in three patients. Responses were obtained only in patients with CD4+,CD8-membrane markers (seven out of 10), and no responses were recorded in any of the nine patients with a different phenotype. In this series remission appeared to correlate with the membrane phenotype of the neoplastic cell and not with the cytopathological diagnosis. Future studies should establish the biochemical basis for the greater sensitivity of CD4+ lymphoid cells to deoxycoformycin.

Adult↗

Alpha, beta and gamma T-cell receptor genes: rearrangements correlate with haematological phenotype in T cell leukaemias.

We have studied the arrangement of the alpha, beta and gamma T cell receptor (TCR) genes in 27 patients with T cell lymphoproliferative disorders. Nine patients had acute lymphoblastic leukaemia (T-ALL), nine patients had prolymphocytic leukaemia (PLL), six patients presented with a T-CLL/T-lymphocytosis syndrome, two patients had Sezary syndrome (SS) and one patient had HTLV-I positive T-cell leukaemia/lymphoma (ATLL). alpha TCR gene rearrangement could be demonstrated by the use of three available probes in only one case. By contrast, both beta and gamma TCR gene rearrangement could be demonstrated by Southern blot analysis of DNA samples digested with appropriate restriction enzymes in the majority of cases. In general, when rearrangements were present they involved both alleles. The proportion of rearranged chromosomes was lower in T-ALL than in other forms of T-cell leukaemia and it was lower in cases with the CD4-/CD8+ phenotype than in those with a CD4+/CD8- phenotype. In three out of 34 cases of B-cell leukaemia the TCR beta-gene but not the TCR gamma-gene was rearranged, just as in two out of 26 cases of T-cell leukaemia the immunoglobulin (Ig) heavy chain but not the light chain genes were rearranged. These data suggest that development of the machinery required for gene rearrangement may precede commitment to B or T cell lineage. The use of this technique is especially useful for the classification of cases of ALL in which the cells are negative with respect to most current phenotypic markers and in cases of T cell lymphocytosis in which the finding of a gene rearrangement identifies a monoclonal cell population.

Adolescent↗

'Pseudo-lymphoid' leukaemia with unusual features: ultrastructural, immunological, cytogenetic and molecular studies.

An unusual case of 'pseudo-lymphoid' leukaemia is described. The leukaemic cells resembled small, mature lymphocytes but lacked B- and T-cell membrane markers as well as immunoglobulin (Ig) and T-cell receptor gene rearrangements. They showed, instead, features of early myeloid cells since they expressed 2 myeloid antigens, CDW13 and My9, and displayed peroxidase activity demonstrable by electron microscopy (EM) on unfixed cells. Cytogenetic studies showed monosomy 5, t(4;17) (p12;p11), t(2;3)(p23;q14) and an abnormal chromosome 12. Abnormalities of chromosomes 4 and 5 have been previously associated with 'pseudo-lymphoid' leukaemias. This case illustrates the value of sensitive methods for the characterization of blast cells and for the precise diagnosis of leukaemias with apparent 'lymphoid' morphology.

Antibodies, Monoclonal↗

Cytochemical profile of megakaryoblastic leukaemia: a study with cytochemical methods, monoclonal antibodies, and ultrastructural cytochemistry.

A cytochemical study using: Sudan black B; alpha-naphthyl acetate (ANAE) staining; estimation of alpha-naphthyl butyrate (ANBE) esterase activity; acid phosphatase activity; and 5' nucleotidase activity was carried out in 15 cases of megakaryoblastic leukaemia. These included cases of M7 acute myeloid leukaemia and blast crises of chronic granulocytic leukaemia. The megakaryoblastic nature of the blasts was first established using two monoclonal antibodies against platelet glycoproteins, and by estimating the platelet/peroxidase reaction at ultrastructural level. Our findings suggest that megakaryoblasts have a typical cytochemical profile comprising positive ANAE staining and acid phosphatase activity with a predominant localisation in the Golgi zone and negative or weak ANBE activity. A similar positive cytochemical pattern was also found in five cases of erythroleukaemia (M6). The specificity of the 5'nucleotidase activity for megakaryoblasts was not confirmed. In most cases of megakaryoblastic leukaemia there was no 5'nucleotidase activity only two cases showed positive reactions--reactions were positive in several cases of myeloblastic and lymphoblastic leukaemia. We suggest that cytochemical methods may be useful in diagnosing M6 and M7 acute leukaemia because less than 40% of leukaemic cells react with specific monoclonal antibodies.

5'-Nucleotidase↗

A t(8;14)(q24;q32) in a T-lymphoma/leukemia of CD8+ large granular lymphocytes.

Chromosome studies in a case of T cell lymphoma/leukemia, in which a high proportion of the dividing cells had a t(8;14)(q24;q32) similar to that seen in Burkitt's lymphoma, are described. The tumor cells had a mature T cell phenotype (TdT-,CD3+,CD8+,CD4-) and were morphologically large granular lymphocytes and immunoblasts, both cell types with similar lysosomal granules in the cytoplasm. The immunoglobulin heavy chain gene and the T cell receptor beta chain gene were not rearranged, while the T cell receptor gamma chain gene was polyclonally rearranged. Mitoses were obtained only from spontaneously dividing cells in the absence of mitogens; 49 of the 50 metaphases analyzed were chromosomally abnormal and had a t(1;22)(q12;q13) and dup(1)(q31q32) in all of them; 48 metaphases had in addition a t(8;14)(q24;q32) which presumably arose during clonal evolution. The latter may be associated with the aggressive behavior of this T cell disorder by comparison with other proliferations of large granular lymphocytes. Although abnormalities involving 14q32 are characteristic of B cell disorders, they have also been described in T cell malignancies, suggesting that genes transcribed in T cells and/or oncogenic sequences significant in T cell neoplasia are present in 14q32.

Adult↗

Cytogenetic studies on prolymphocytic leukemia. II. T cell prolymphocytic leukemia.

We report chromosome abnormalities in 15 cases of T cell prolymphocytic leukemia (T-PLL). All cases were characterized by clinical, morphological, and membrane marker analysis. The most frequent abnormality was an inv(14)(q11q32) observed in nine cases. The T cell receptor (TCR) alpha chain gene is localized to 14q11 and the immunoglobulin heavy-chain gene to region 14q32. Four cases also had translocations involving 14q11. Trisomy or multisomy for 8q resulting from an i(8q) or from rearrangements with 8p12 as the breakpoint was observed in nine cases, and a deletion of 6q was found in four cases. Trisomy or partial trisomy for 7q was observed in four cases, of which two had abnormalities of band 7q35 to which the TCR beta chain gene is mapped. The expression of Tac antigen, investigated in 27 cases of human T cell leukemia virus I-negative chronic T cell leukemia, which included the 15 cases of T-PLL, showed a good correlation with abnormalities of 7q35. Our studies on chronic T leukemias suggest that inv(14)(q11q32) and trisomy for 8q are abnormalities characteristic of T-PLL.

Antibody Diversity↗

Morphological heterogeneity of Leu7, Leu11 and OKM1 positive lymphocyte subsets: an ultrastructural study with the immunogold method.

The morphological features of normal peripheral blood lymphocytes reactive with three monoclonal antibodies (MoAb) against natural killer (NK) cells, Leu7, OKM1 (CD11b) and Leu11 (CD16) and with two anti-T cell MoAb, CD4 and CD8, have been analysed at ultrastructural level by an indirect immunogold method. Cells having the features of large granular lymphocytes (LGL) but also lymphocytes displaying different morphological characteristics (non LGL; e.g. high nucleo-cytoplasmic ratio and few cytoplasmic organelles) were seen reactive with each of the MoAb investigated. Leu7 identified a higher proportion of LGL (60-80%) than OKM1 (10-95%) and Leu11 (20-48%), and with a stronger binding. A distinct granular structure, recognized as parallel tubular arrays, was more characteristic of the Leu7+, CD8+ LGL and was less frequently seen in the OKM1 and Leu11 positive LGL subpopulation in four out of the five donors investigated. It is of interest that the Leu11 and OKM1 positive subsets, which correspond functionally to cells with greater NK function, had relatively less LGL than the Leu7 positive subsets, raising the issue of the true morphology of NK cells in man. The existence of a minority of CD4 positive LGL was confirmed. Our findings demonstrate that there is a degree of morphological heterogeneity within the normal NK lymphoid population as defined by the membrane phenotype and that certain variability among normal individuals regarding the proportion and structural features of the NK subpopulations may be present.

Antibodies, Monoclonal↗