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M Trucco

Publications and source records attributed to M Trucco.

At least 199 records · Page 11Linked to original sources
PubMed1987

Allelic forms of the alpha- and beta-chain genes encoding DQw1-positive heterodimers.

On chromosome 6, in the HLA region, the DQ subregion is located immediately centromeric to the DR subregion. Even though only three serological specificities to date have been officially recognized (DQw1, DQw2, and DQw3), it seems likely that the phenotypical polymorphism expressed by DQ molecules is much more complex. There are reasons to believe that fixed alpha-beta combinations exist, each of them associated with a different DR allele. DQw1 is a determinant present on DQ molecules that are found associated with DR1-, DR2-, and DRw6-positive haplotypes. By restriction fragment length polymorphism analysis, we recognized three allelic DQ-alpha and three allelic DQ-beta patterns associated with DQw1. In addition, one of these alpha/beta pairs associated with DR1, two with DR2, and a fourth with DRw6. We have obtained evidence using nucleotide sequencing that there are as many allelic forms of DQ-alpha and DQ-beta genes as there are different molecular DQ-alpha and DQ-beta patterns. The DQ-alpha and DQ-beta chains of DQw1-positive molecules each are encoded by at least three distinctly different allelic genes, and particular alpha/beta gene combinations are associated with the same DR alleles as their corresponding molecular alpha/beta pairs.

Alleles↗
PubMed1987

Alloreactive T-cell recognition of two DQ beta allelic specificities associated with DQw1.

Two sets of alloreactive T-cell clones from different original mixed lymphocyte reactions (MLR) discriminate between two DQ beta allelic forms when these are expressed in association with the same DQ alpha form. From these results we concluded that it is possible to guide a DQ specific response of alloreactive T-cell clones by setting up an appropriate responder-stimulator combination in the original MLR; DQw1 is associated with two allelic forms of the DQ molecule recognized as lymphocyte activating determinants by alloreactive T-cell clones; alloreactive T cells recognize specific alpha-beta chain combination of the DQ molecule; the allelic forms that differentiate the alpha or the beta chains of the DQ molecule from each other can also be recognized at the molecular level by DQ alpha and DQ beta RFLP analysis.

Alleles↗
PubMed1986

[Evaluation of the effects of citicoline in chronic cerebrovascular diseases].

A double-blind random block trial was carried out on 58 patients suffering from chronic cerebrovascular diseases as defined by the "Ad Hoc Committee, Paris 1980". The trial was carried out to assess the effects of citicoline on chronic cerebrovascular disease. Particular attention was paid to the selection of the assessment tools (neuropsychological and psychological tests). Citicoline treatment brought about an improvement in awareness and perceptive-motor faculties. This effect can be attributed to an overall drug action on neural energy metabolism.

Aged↗
PubMed1986

HLA-DQ polymorphism analyzed by sequential restriction endonuclease DNA digestion.

A direct, physical correspondence between certain Pst I-generated genomic DNA fragments and Taq I-generated fragments, revealed with HLA-DQ alpha or -DQ beta gene probes, has been demonstrated. As an immediate consequence, the nature of the DQ and DX hybridized genes contained in the fragments was established. Taq I-generated DQ allelic forms which associate with serologically defined DR1, DR2, and DRw6 specificities were also proven to be sensu stricto "splits" of the Pst I-generated allelic form associated with all three DR specificities.

Alleles↗
PubMed1986

DQ alpha and beta RFLP reveals the composition of the DQ molecule recognized by T-cell clones.

Pst I RFLP, revealed with DQ alpha and DQ beta probes, was compared with Taq I RFLP using a panel of DR-homozygous cell lines and HLA-typed family members. Taq I patterns, characteristic for each DR-associated DQ alpha and beta allelic forms, were recognized in the homozygous state and then proven to segregate in the heterozygous members of informative families. The presence of both specific alpha and beta chains was found to be necessary to form the type of DQ molecule specifically recognized by two alloreactive T-cell clones. Particular alpha and beta associations also seem to be responsible for some Dw splits of the DRw6-positive cells. Taq I RFLP analysis may be more complex than the Pst I analysis, but is certainly more informative and complete, considering the type of information we were seeking by performing these types of experiments.

Alleles↗
PubMed1985

Inhibitory effect of a human T cell hybrid factor on both cell growth and mixed lymphocyte reactivity. Correlation with class II molecule expression.

We recently reported the biological activity and some of the biochemical characteristics of a factor produced by a human T cell hybrid clone able to block hematopoietic progenitor cell proliferation. This 85-kD protein factor, which we have termed colony-inhibiting lymphokine (CIL), has growth regulatory activity on bone marrow precursors bearing Ia (class II) antigens of either granulocytic-monocytic (CFU-GM) or erythroid lineage (BFU-E and CFU-E). Experiments aimed to investigate the specificity of the inhibitory effect on hematopoietic progenitor cell growth suggested that the expression of HLA-DR surface antigens was required on the target cells. We describe in this communication how DR+ cell lines ceased dividing after a few days of culture in the presence of CIL, whereas DR- cell lines were completely unaffected. The increased DR expression on the ML3 cell surface, mediated by the activity of the gamma interferon (IFN gamma), increases the sensitivity to the growth inhibition factor of the ML3 cell line. To verify the hypothesis that the DR antigens might serve as receptors for the factor, enabling it also to interfere in the immune response, we tested CIL in a mixed lymphocyte reaction (MLR), one of the best known in vitro Ia antigen-dependent T cell-mediated immune responses. CIL is able to block major histocompatibility complex-allogeneic MLR both in human and mouse systems. The data indicate that CIL recognizes a nonpolymorphic structure (presumably on all Ia molecules) presented by stimulator cells of either species, and thereby interferes with specific interactions between stimulator and responder cells. Blocking of the alloantigen stimulation stage is also indicated, since CIL is effective only if added to the culture medium during the first 48 h of the MLR. Finally, mouse monoclonal anti-DR antibodies are able to sharply reduce CIL activity on sensitive DR+ cell lines. CIL may act physiologically as a multifunctional mediator in a complex network that links regulation of bone marrow differentiation and the generation of immune responses.

Animals↗
PubMed1985

Antimigraine drugs in the management of daily chronic headaches: clinical profiles of responsive patients.

Flunarizine, a Ca-antagonist with demonstrated antimigraine properties, and indoprofen, an anti-inflammatory non-steroidal agent, were used in the treatment of daily chronic headache. Forty-two migraineurs with interval headache (MIH) were treated with flunarizine in a 6-month open trial, while indoprofen was administered to 23 patients with MIH and 7 with chronic tension headache (CTH) in a 2-month, double-blind, cross-over placebo-controlled study. Flunarizine was found effective in over 65% of the patients, while indoprofen was able to improve headache severity in only 30% of the subjects. In the responder patients, the effectiveness of both drugs is more pronounced in MIH, and seems to be ascribable to the ability of the treatments to reduce number and severity of attacks. A higher incidence of previous affective disturbances is found in non-responsive cases. The analysis of factors converting episodic into chronic headache shows slight but not significant differences between responders and non-responders. An impairment of plasma beta-endorphin levels, in the presence of normal ACTH, cortisol and nociceptive RIII threshold values, characterizes daily chronic headache (DCH) patients. Moreover, indoprofen does not significantly affect these biological and neurophysiological parameters independently of the therapeutic response.

Adult↗
PubMed1985

Generation of natural killer-like activity in mixed lymphocyte-tumor cell cultures. I. Role of HLA-DR antigens as stimulatory molecules.

A number of human lymphoid and non-lymphoid leukemic cell lines differing for expression of HLA-DR antigens were analyzed for the ability to induce natural killer(NK)-like activity and proliferation in lymphocytes from healthy donors. The ability to elicit the generation of NK-like activity in the responder lymphocytes varied greatly depending upon the type of antimitotic treatment (gamma-irradiation versus mitomycin C) received by the tumor cells prior to the start of the mixed cultures. By contrast, the induction of T-cell proliferation was positively correlated with the presence of DR molecules on the tumor cell lines. Nevertheless, DR- leukemic cells pretreated with the appropriate antimitotic agent did induce a proliferative response in the mixed cultures. T lymphocytes cultured without stimulator cells in spent medium containing high levels of cell-free DR antigens failed to undergo blastogenesis and proliferation, indicating that DR antigens can function as stimulatory molecules only when they are cell-associated.

Cell Line↗
PubMed1984

Flunarizine: a wide spectrum prophylactic for migraine headache.

The effects of flunarizine in migraine headache were investigated in 40 patients treated with single 10 mg evening doses for 16 weeks. Standard criteria were adopted for patient admission and for the monitoring of clinical (headache index, consumption of analgesics, side-effects) and laboratory variables (platelet aggregation and red cells filterability). Significant positive effects were found in 31/40 cases irrespective of the clinical course of the disease (i.e., recurrent attacks or more or less chronic forms). Some baseline characteristics of the patients are discussed on the basis of the therapeutic response.

Adult↗
PubMed1983

Differentiation antigens of human hemopoietic cells: patterns of reactivity of two monoclonal antibodies.

Two mouse anti-human monoclonal antibodies (S3.13 and S5.7) raised against cells of acute myelogenous leukemia were found to react with antigens expressed on the surface of subsets of monocytes and lymphocytes. S3.13 precipitates a peptide of Mr 29,000, and S5.7 precipitates a peptide of Mr 20,000 present on the surface of all the cell types tested. These two surface antigens were distributed on discrete subpopulations of normal hemopoietic cells. The antibodies reacted with all (S5.7) or a subpopulation (S3.13) of peripheral blood T-lymphocytes, and with a subset of monocytes. Both antibodies reacted with bone marrow blast cell progenitors of the myelomonocytes and erythroid lineage. S5.7 also reacted with non-T-lymphocytes and with cells of the eosinophilic lineage. Both antigens disappeared from the cell surface during normal myeloid and erythroid differentiation. Thus, these monoclonal antibodies define the molecular characteristics and the cellular distribution of two differentiation antigens present on cells of the hemopoietic lineage.

Animals↗
PubMed1982

A monoclonal antibody that detects expression of transferrin receptor in human erythroid precursor cells.

A monoclonal antibody, L5.1, obtained by immunizing a Balb/c mouse with HL60 human promyelocytic leukemia cells, was found to react with both HL60 cells and with the K562(S) cell line. This monoclonal antibody binds and immunoprecipitates a glycoprotein (Mr 87,000) present on the cell surface membrane of K562(S) as a disulfide bonded dimer. In competition experiments L5.1 competes with both transferrin and OKT9 (a known antitransferrin receptor antibody) for binding to target K562(S) erythroleukemia cells. Binding of both L5.1 and transferrin to the surface of K562(S) cells is inhibited by treatment with 12--O-tetradecanoyl-phorbol-13-acetate, and the extent and time course of inhibition is similar in both cases. Cell sorting analysis of normal human marrow cells incubated with L5.1 indicates that L5.1 reacts strongly with all the morphologically recognizable erythroid lineage precursors, from the pronormoblast to the orthochromatic normoblast, and with reticulocytes. Erythrocytes, myeloid elements, monocytes, megakaryocytes and platelets, peripheral blood B and T lymphocytes do not bind significantly with this antibody and only a small fraction of promyelocytes was reactive. Antibody L5.1 did not react with leukemic cells of patients with acute lymphoblastic, myeloblastic and promyelocytic leukemias, but it did react with some established B (1 of 5) and T (2 of 3) cell lines, and a myeloid (1 of 3) cell line, and with PHA-stimulated peripheral blood lymphocytes. The nonhemopoietic cell lines tested did not bind with L5.1 with the exception of a colorectal adenocarcinoma and a melanoma cell line, which were both strongly positive. The relationship of antibody L5.1 to other monoclonal antibodies that bind the transferrin receptor is discussed.

Animals↗
PubMed1981

A xenogeneic monoclonal antibody recognizing specificities controlled by HLA-A and B alleles.

In the present paper one reagent among the many prepared has been carefully studied. It is a xenogeneic monoclonal antibody, F10.13/13, obtained by immunizing mice with human peripheral blood lymphocytes. The splenocytes of the immunized mice were fused with a murine were fused with a murine myeloma and the supernatants of the resulting Ig-secreting hybridomas were tested against appropriate targets. --F10.13/13 behaves in a very peculiar manner from the serological point of view and we think that it reacts with maximal affinity with an epitope expressed most strongly on HLA glycoproteins controlled by genes B8, B7, and Aw19.

Alleles↗
PubMed1981

Modulation of expression of HLA components at the cell surface induced by anti-beta 2m reagents.

Antibodies against lymphocytes surface components are able to rearrange profoundly the topography of the cell membrane with a differential modulation of surface antigens. Of particular interest is the effect of anti-beta 2m reagents, which are able to suppress completely the reactivity of epitopes carried by the two chains of the ABC dimers, while th expressivity of other antigens, such as DR, is significantly increased. These results have been obtained with immunoradiobinding under a variety of conditions, thus confirming the validity of the "bb" (beta 2m blanketing) test.

Animals↗
PubMed1980

Quantitative analysis of cell surface HLA structures by means of monoclonal antibodies.

Quantitative data on the binding of murine monoclonal antibodies ot whole human lymphoblastoid lines and peripheral blood lymphocytes (PBL) are reported. Antibodies reacting with beta 2m or a common part of the HLA heavy chains and nonpolymorphic determinants of the DR dimer were used. The equilibrium constant (K) of the reaction and the total number of antigenic determinants was graphically estimated. For the above-mentioned antibodies, K ranged between 5 X 10(8) and 4 C 10(9) l/mole at 0 degrees C and progressively decreased with the increasing temperature. T cells expressed less HLA and beta 2M determinants than the B cells. The number of determinants per surface unit is higher on the B cell from PBL than on E.B. virus-transformed cell lines and is generally very low, suggesting that the complement-dependent cytotoxic activity is a phenomenon depending on membrane fluidity. A portion of beta 2m seems not to be bound to the HLA heavy chains on B cells as well as on T line surface, as already shown for Molt 4 line.

Antibodies↗
PubMed1979

Separation of human cells bearing HLA-DR antigens using a monoclonal antibody rosetting method.

A technique is described for enriching, from human blood, cells bearing HLA-DR antigens. The method depends on the use of monoclonal mouse antibody which reacts with HLA-DR structures. Cells to which this antibody has bound can be separated after rosetting with bovine erythrocytes coated with anti-mouse immunoglobulin. The cells thus enriched may be used for HLA-DR typing by standard cytotoxicity methods with allogeneic sera.

Antibodies, Anti-Idiotypic↗