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Biomedical subjects

J Dausset

Publications and source records attributed to J Dausset.

At least 181 records · Page 10Linked to original sources

HLA system and side effects of gold salts and D-penicillamine treatment of rheumatoid arthritis.

Among 67 patients with rheumatoid arthritis treated with gold salts (aurothiopropanol sulphonate) a significant correlation (p less than 10(-2)) was noted between gold toxic reactions, whatever their type, and the HLA antigens A1, B8, Cw7, and DR3. Forty-two patients were genotyped, and a correlation was observed between gold side effects and the haplotype A1 Cw7 B8 DR3 (p less than 10(-2), RR = 8.0). In addition 3 out of 4 cases of renal intolerance to D-penicillamine were observed in patients possessing the Cw7 B8 DR3 haplotype.

Adult↗

Alloantigens expressed on activated human T cells different from HLA-A, B, C, and DR antigens.

This study investigates alloantisera containing antibodies directed against antigens which are expressed on alloactivated human T lymphocytes but are absent on resting T and B cells. Among 39 defined anti-HLA-DR sera from multiparous women we found six sera giving positive reactions (more than 25 percent cytotoxicity) on in vitro alloactivated T cells, though negative reactions with resting B or T cells from the donors of either the responding or stimulating cell populations used for alloactivation. Two such sera were submitted to absorption and elution studies. Absorption of these sera with activated T cells did not remove the anti-HLA-DR activity. Furthermore, the antibodies eluted from activated T cells did not react with B cells but were positive only on activated T cells. In addition, we absorbed the sera with B cells and observed that they remained positive on activated T cells. The positive reactions do not seem to be due to either the passive acquisition of antigens from the stimulating population or to low levels of HLA-specific antibodies. As one of the sera we studied intensively gave clear positive and negative reactions on a panel of activated T lymphocytes, we believe it may recognize an antigen of an allogeneic system expressed on alloactivated human T cells.

Antibody Specificity↗

Regulation of the human allogenic proliferative response in vitro. II. Production of soluble suppressor factors by suppressor T cells and evidence in favor of "acceptor" cells for suppression among unprimed lymphocytes.

It has previously been shown that presensitized cells in culture medium release suppressor factors (SF) which can inhibit a primary mixed leukocyte reaction (MLR I). This occurs when the presensitized cells are resensitized with an HLA-DR-specific cell, which can be either the primary stimulator or any other DR-identical allogeneic cell. The autologous responders (SF producer cells) and certain allogeneic cells are suppressed, which suggests that restriction takes place. In this paper the effect of preincubation of responder or stimulator cells in SF has been studied: (1) When unprimed responders are preincubated with the suppressor supernates (SF) and tested in MLR I against several stimulators, the cells of the autologous SF producer and certain other allogeneic cells are always inhibited as already observed when SF was added directly to a mixed lymphocyte culture. (2) When the same stimulators are preincubated with the same SF and used as stimulators with the same responders (not preincubated) then inhibition is observed without restriction. This difference in behavior suggests the existence of at least two factors, one acting through stimulators on all responders. (3) Filtration of unprimed responders through glass wool (before SF preincubation and coculture with stimulators in MLR I) produces nonadherent T cells which are suppressed more after preincubation with SF than the same cells unfiltered. This could be due to the existence of a subset of "acceptor" cells. (4) None of these factors has immunoglobulin characteristics. Their molecular weights are between 40 000 and 70 000 daltons.

Histocompatibility Antigens Class II↗

Screening and use of high titered anti-HLA-DR sera in PHA-blast complement fixation and B-lymphocytotoxicity techniques.

Screening for anti-HLA-DR sera was performed by complement fixation on PHA stimulated peripheral blood lymphocytes (PHA-CF), or cultured B lymphoid cell lines. Out of 1,350 sera from multiparous women, multitransfused patients, and patients transfused during extra-corporal circulation (ECC), 219 contained anti-HLA-DR activity (16.2%). Anti-HLA-DR antibodies developed after ECC were often high titered (1:10 to 1:100). In half of these sera anti-HLA-A, B antibodies were weak or absent, making it possible to use then as anti-HLA-DR reagents without platelet absorption. Of the 219 positive sera 51 contained defined anti-DR antibodies (20 monospecific and 31 bi- or multispecific). The 13 best sera recognized DR1 and DR7 specificities with r values from 0.83 to 1. Twenty-four sera selected by CF were also studied by lymphocytotoxicity technique against peripheral blood B lymphocytes (B-LCT). Both PHA-CF and B-LCT techniques gave similar results, detecting the same specificities and showing comparable sensitivity. The advantages of CF are: easy storage of target cells at -80 degrees C or + 4 degrees C, and fast reading. For these reasons PHA-CF or CF on cultured B lymphoid cell lines can be proposed for large scale screening of anti-HLA-DR sera. The sera thus screened can be used for HLA-DR typing either by PHA-CF or B-LCT.

Antibodies↗

Cell surface characterization of malignant T cells from lymphoblastic lymphoma using monoclonal antibodies: evidence for phenotypic differences between malignant T cells from patients with acute lymphoblastic leukemia and lymphoblastic lymphoma.

A series of monoclonal antibodies was used for the characterization of malignant T cells from 21 patients with lymphoblastic lymphoma (LL). The tumor population from these patients showed a marked degree of phenotypic heterogeneity and a proportion (one-third) of patients had tumor cells that did not conform exactly with the cells normally detected in the thymus. However, these cell populations could be related to the early or common or late thymocyte population (about one-third of the patients in each category). This contrast, with the characterization of malignant T cells from 43 patients with acute lymphoblastic leukemia (ALL) that could be related to either early or common thymocytes, with an exception of two patients categorized as having a tumor population related to late thymocytes. Further phenotypic differences between cells from ALL and LL could be demonstrated by investigation with two additional monoclonal antibodies, A50 and U4. Among patients with malignant T cells related to common thymocyte, 0/12 patients with ALL had cells recognized by A50, where 5/8 patients with LL had A50+ cells. Among patients with early thymocytes, only patients with ALL had cells recognized by U4. In addition, 5 LL patients had cells reactive with J5, a monoclonal antibody recognizing the common ALL antigen (CALLA). Since CALLA was found on cells related to common and late thymocytes, CALLA is neither lineage specific, nor can it be viewed as being peculiar to malignant lymphoid cells arrested at very immature stages of differentiation.

Adolescent↗

Surface antigens on malignant Sézary and T-CLL cells correspond to those of mature T cells.

Tumor cells from eight adult patients with T-cell chronic malignancies were investigated with a series of monoclonal antibodies recognizing T-cell differentiation antigens. This series allowed definition of discrete subpopulations of mature T cells with functional specialization. All six patients with Sézary syndrome and one patient with T-chronic lymphocytic leukemia had cells with the same phenotype as normal helper/inducer T cells, whereas the other patient with T-chronic lymphocytic leukemia had cell with the same phenotype as normal cytotoxic/suppressor T cells. Some clinical manifestations observed in these patients may reflect retention of functional activities by their malignant cells.

Antibody Specificity↗

HLA markers in patients suffering from aplastic anaemia.

135 patients, suffering from aplastic anaemia (AA) and their families were genotyped for HLA. The antigen and haplotype frequencies were compared to an HLA genotyped control panel composed of 209 normal couples and their healthy offsprings, and to another series of 2286 normal individuals. An excess of HLA-A2 was observed in the patients: 61% versus 42% (pc less than 0.001) (relative risk: 2) and versus 48.5% (p less than 0.01) in two control series, respectively. When considering the HLA-A, B antigens shared in common by the parents of the AA patients, an excess of HLA-A2 was observed: 32% as compared to 17% shared by normal couples (p less than 0.001). An excess of homozygous HLA-A2 was noted in the AA patients (14%) in comparison to the normal controls (4%) (p less than 0.001). The mechanism of this association is discussed as well as the hypothesis of a gene involved in haematopoiesis which might interact within the HLA-A region.

Anemia, Aplastic↗