Impairment of immunogenicity by antigen presentation in liposomes made from dimyristoylphosphatidyl‐ethanolamine linked to the secretion of prostaglandins by macrophages

摘要

AbstractThe induction of antibody response in syngeneic rats by the Gross virus cell surface antigen (GCSAa) was dependent on the presentation of GCSAa into liposomes made from distearoylphosphatidylcholine (DSPC). GCSAa liposomes made from dimyristoylphosphatidylethanolamine (DMPE) were nonimmunogenic, even when used as anamnestic immunogens. Spleen cells, from rats twice immunized with GCSAa‐DSPC‐liposomes and used to transfer the anti‐GCSAa immune response into naive recipients after a tertiary immunostimulationin vitroin the presence of naive peritoneal exudate cells (PEC), responded to soluble GCSAa only after irradiation at 500 rds and to GCSAa‐DMPE‐liposomes only when indomethacin was added during thein vitrostimulation. The preincubation of these cells with empty DMPE liposomes or the addition of supernatant from PEC fed with DMPE liposomes abrogated the response to GCSAa‐DSPC liposomes. Using a specific radioimmunoassay, prostaglandin E2was demonstrated to be produced by PEC when fed with DMPE liposomes, and not when fed with DSPC liposomes. This prostaglandin E2secretion by PEC induced by DMPE liposomes was inhibited by i