[Modulation of the lymphocyte membrane with anti-HLA ABC in psoriasis]

Antibodies against lymphocyte surface antigens are able to rearrange the topographic of the cell membrana. This is the first event of immune cell functions for motility and cell adherence. Take in account: the high incidence of some HLA antigens in psoriasis and that the HLA system is involved in the genetic control of immune responses, we studied the reaction of anti HLA antibodies against lymphocytes from 16 patients with active psoriasis and from six healty controls. For this: lymphocytes T or B are sensitized with optimal amounts of anti HLA ABC antibodies. They are washed and resuspended in a nutrient medium and incubated at 37 degrees C. At 0, 3, 4, 5 and 6 hours samples are taken and observed for microlymphocytoxicity after addition of complement. Controls for viability and for antigenic sites are made. The addition of complement shows a decrease in the cytotoxic reaction. This is due to the loss from the cell surface of the antigen-antibodies complexes. The observed phenomenon is paralleled to the rearrangement of membrane proteins and is developed in a similar period to the normal antigen turnover time. Our results demonstrate a significative decrease in the turnover for HLA ABC molecules at the cell surface of T lymphocytes from psoriasic patients, that we assimilate to an altered rearrangement of HLA ABC molecules. No significative differences was observed for the turnover of HLA ABC molecules at cell surface of B lymphocytes. The altered T lymphocyte membrane demonstrate an immunobiologic defect and it may the explanation for the impairment for the T cell function in psoriasis.(ABSTRACT TRUNCATED AT 250 WORDS)