Hyporesponsiveness to a GnRH vaccine in a non-responder mouse strain is T-cell mediated.
Immunization of rats and monkeys with the decapeptide gonadotropin releasing hormone (GnRH) linked to carriers such as diphtheria toxoid (DT) or tetanus toxoid (TT) results in a marked atrophy of the prostate. This vaccine is now being explored for its potential in the "immunosurgery" of prostatic hypertrophy in men and is currently undergoing Phase I/II clinical trials. We have been investigating immunogenetic aspects of immune responses to this hapten-carrier conjugate, and in a recent communication we described the responses of different strains of mice to GnRH conjugated to DT (GnRH-DT). Mice of the 129 (H-2b) strain were found to be non-responders to GnRH. However, further immunization of GnRH-DT-immunized 129 mice with GnRH linked to an alternate carrier, TT, resulted in the production of high levels of anti-GnRH antibodies. This showed that 129 mice are not deficient in GnRH-specific B cells and that the lack of response to GnRH in 129 mice is possibly due to (i) the lack of appropriate helper T-cells or (ii) the presence of suppressor cells. In this report we present evidence to support the existence of suppressor cells in GnRH-DT-immunized 129 mice.
Sad
S
S
National Institute of Immunology, New Delhi, India.
Gupta
H M
HM
Talwar
G P
GP
Raghupathy
R
R
D000818:Animals; D004168:Diphtheria Toxoid; D007987:Gonadotropin-Releasing Hormone / Q000276:immunology*; D007111:Immunity, Cellular; D016219:Immunotherapy, Adoptive; D000922:Immunotoxins / Q000276:immunology*; D051379:Mice; D008815:Mice, Inbred Strains; D013601:T-Lymphocytes / Q000276:immunology*; D013745:Tetanus Toxoid
D004168:Diphtheria Toxoid; D000922:Immunotoxins; D013745:Tetanus Toxoid; D007987:Gonadotropin-Releasing Hormone