Hapten, carrier recognition and response by immunocytes of the primitive vertebrate, Notophthalmus viridescens

Abstract

These experiments were designed to test whether newt (Notophthalmus viridescens) immunocytes are able to recognize the hapten, 2,4,6-trinitrophenyl (TNP), separately from a heterologous erythrocyte (RBC) carrier. While a single priming injection with an erythrocyte species which is unrelated to the carrier of the TNP fails to stimulate amplification of the anti-TNP response, sequential (2X) priming provides about 50% as much amplification as a single priming injection of RBC homologous with the carrier. The anti-carrier response is not increased by sequential priming with the unrelated RBC. Moreover, sequential priming with RBC homologous with the carrier species initiates a suppression of the anti-hapten response without affecting anti-carrier activity levels. Thus the recognition and regulation of responses to a hapten and its carrier may be unlinked in this species.