Soon after tolerance induction, cross-reactive avian lysozymes terminate tolerance to hen lysozyme (HEL).3 The production of cross-reactive antibody at this stage indicates that the bone marrow-derived (B) cell compartment is still non-tolerant. Later, B cell tolerance is also induced, but it requires a longer exposure and a higher dose of antigen than does induction of thymus-derived (T) cell tolerance.
At a time during recovery from neonatal or adult tolerance to HEL, when HEL-reactive B cells can again be demonstrated, mice challenged with turkey lysozyme (TEL) produce only TEL-specific antibody. The possibility is suggested that TEL-specific B cells compete more favorably for available antigen than do the newly returning, cross-reactive B cells.
The reduced response to challenge in tolerant animals is discussed in relation to a model in which there are stringent stereospecific rules governing the presentation of antigen to B cells.
This work was supported by Grants GB 5410 from the NSF and AI 08198 from the United States Public Health Service. R.S. was the recipient of a predoctoral fellowship (5-F01-GM-35, 714) from the National Institutes of Health.
Abbreviations used in this paper: GEL, gallinaceous egg white lysozymes, where B is bobwhite quail, H is hen, J is Japanese quail, P is pea hen, R is ring-necked pheasant and T is turkey. Additional abbreviations: T, thymus-derived; B, bone marrow-derived; PT, post-administration of tolerogen; BSA, bovine serum albumin.