Age-related humoral antibody responses of AKR/J mice to T-cell dependent and independent antigens

Abstract

Humoral responses of groups of 2–3 and 6–7-month-old preleukaemic AKR/J and SWR/J mice were determined following immunization with T-cell dependent (SRBC) and independent (Sal. enteritidis or B. abortus) antigens. Young AKR/J mice responded well to whole SRBC but were less consistent in their responses to lysed SRBC. A greater proportion of the anti-SRBC response in this strain was also due to ME-sensitive antibodies than in the SWR/J strain. Older AKR/J mice had lower averages in total antibody responses and a more rapid decline in maximum titres than younger animals of the same strain. Minimal humoral responses to the T-cell independent antigens were seen in these two strains of mice. Responses of both age groups of AKR/J mice were characterized by an absence or marked depression in detectable ME-sensitive antibodies. Older AKR/J mice were again less responsive to the Salmonella antigen than young AKR/J mice. Simultaneous injection of animals with Sal. enteritidis and SRBC antigens resulted in selective inhibition or reduction in detectable ME-sensitive anti-SRBC responses in the AKR/J strain of mice. It is concluded that in conjunction with a progressive viral-induced malignant disease and associated impairment of cell-mediated responses that AKR/J mice also develop a corresponding immunological imbalance in humoral responses. From results of this study, this can be seen to have an increasing effect with ageing upon the type and amount of antibodies produced to T-cell dependent and independent antigens.