IN-VITRO STIMULATION OF NAIVE MOUSE LYMPHOCYTES BY HELIGMOSOMOIDES-POLYGYRUS ADULT WORM ANTIGENS INDUCES THE PRODUCTION OF IGG1

The production of high levels of IgGl, by mice chronically infected wi th the parasitic nematode Heligmosomoides polygyrus, has been document ed for a number of years. In order to investigate this phenomenon, nai ve lymphocytes from B10.D2 mice were incubated in vitro with H. polygy rus adult worm homogenate (AWH) and the culture supernatants examined for immunoglobulin production. Stimulation of pooled naive splenocytes gy AWH was found to produce IgGl, but not IgM, in an antigen dose dep endent manner. Identical stimulation of splenocytes of individual inbr ed mice, indicated that this effect was reproducible but with consider able variation between mice. When the IgGl produced was tested for spe cificity, it was found that there was little evidence that the immunog lobulin produced was able to bind to the inducing parasite antigens. A nalysis of purified T cells reconstituted with splenocytes, demonstrat ed that T cells were the target lymphocytes of the stimulating molecul e, contained within AWH. These results show that H. polygyrus AWH can induce the production of non-parasite specific IgGl from naive splenoc ytes and that this production is crucially dependent upon the cell con tent of the in vitro culture. Furthermore, the production of IgGl is n ot proportional to the degree of lymphocyte proliferation. It is sugge sted that at least part of the hypergammaglobulinaemia produced during a primary H. polygyrus infection, is due to this non-specific stimula tion of mouse lymphocytes by the parasite.