Immunologic suppression after oral administration of antigen. II. Antigen-specific helper and suppressor factors produced by spleen cells of rats fed sheep erythrocytes
Mattingly, J.A.; Waksman, B.H.
Journal of Immunology 125(3): 1044-1047
1980
ISSN/ISBN: 0022-1767 PMID: 6157718 Document Number: 164691
Spleen cells from rats given sheep erythrocytes (SRBC) orally were cultured for 48 h in the presence of SRBC. The supernatant of this culture had 2 SRBC-specific activities, 1 that helped and 1 that suppressed the in vitro antibody (PFC [plaque-forming cells]) response to the specific antigen. Neither factor affected the response to horse erythrocytes. The helper factor, THF, has a MW of 30-45 .times. 103, and appears to act only on syngeneic cells. The suppressor factor, TSF, has a MW of 60-75 .times. 103 daltons, and suppressed the PFC response of 3 allogeneic strains differing at AgB. THF was not produced by cells of donors thymectomized as adults and then fed SRBC, but its production was inhibited by treatment of fed animals with anti-lymphocyte serum (ALS); production of TSF was inhibited by ALS treatment and unaffected by thymectomy of the donors. THF enhanced the PFC response of cultures when added at any time in the 1st 72 h, and produced a maximal suppressive effect only if added in the 1st 24 h. THF helper activity was expressed only in the presence of intact T [thymus-derived] cells. In the whole supernatants, TSF shows a dominance in activity over THF, since suppression is always obtained by using the unfractionated supernatants.