An inverse relationship between T cell receptor affinity and antigen dose during CD4(+) T cell responses in vivo and in vitro

Multimeric peptide/class II MHC staining reagents were synthesized and show n to bind with appropriate specificity to T cell hybridomas, A small, expan ded population of T cells detected with one of these reagents in peptide-im munized C57BL/10 mice persisted for several months. This population expande d further on secondary immunization. Equating the extent of binding of this reagent to T cell receptor affinity, we saw little correlation of immunizi ng peptide dose to T cell receptor affinity at the peak of the primary resp onse. However, there was an inverse relation between peptide dose and the a pparent receptor affinity of the T cells that were present several months a fter a primary response or after a secondary stimulation either in vivo or in vitro.