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B Paradis

Publications and source records attributed to B Paradis.

17 recordsLinked to original sources
PubMed1978

Immunologic aspects of psoriasis. III. Fc-gamma-receptor bearing mononuclear cells in peripheral blood.

An anti-IgG activity has previously been reported at the cellular level in patients with psoriasis. This activity was demonstrated by the so-called 'rheumatoid' rosette test. In the present work the nature of 'rheumatoid' rosette-forming cells was studied in comparison with other EA rosette techniques. The use of purified cell populations showed that the lymphocytes participating in the 'rheumatoid' rosette phenomenon were lacking conventional T and B cell membrane markers, and were thus referred to as null cells. Such mononuclear cells bearing a receptor for the Fc part of IgG were able to act as killer cells to IgG-coated target cells. The cytotoxic activity was mainly restricted to a small proportion of lymphocytes forming 'rheumatoid' rosettes which had a high avidity for EA complexes. Such cytotoxicity could contribute to the aetiology of lesions in psoriasis.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1978

[Fc-gamma-receptor cells and rheumatoid arthritis].

Certain blood lymphocytes of patients suffering from rhumatoid arthritis (RA) and or control subjects, can be detected using a rosette technique in the presence of erythrocyte antibody compounds (EA). The EA rosettes demonstrate the presence of cells having a receptor for the Fc fragment of the IgG's (Fc-receptor). A significant increase in highly active EA rosettes during RA was demonstrated using six EA compounds differing according to the type of erythrocyte and the quantity of sensitizing antibody. These highly active EA rosettes correspond to the case in which few antiserum molecules cover the erythrocytes. Their high level in RA may correspond to an increased number of Fc-receptor cells or to a stronger linkage of EA compounds. The cells forming EA rosettes are responsible for the resulting cell antibody cytotoxicity that seems to change little during rhumatoid disease. However, the very special behavior of Fc-receptor lymphocytes incubated in vitro suggests that the IgG receptors are modulated by the immune compounds present during RA.

Adult↗