The enhancement of a primary in vitro anti-hapten response by carrier priming.

Abstract

AbstractThe primary in vitro antibody response of mouse spleen cell suspensions to the hapten 4‐hydroxy‐3‐iodo‐5‐nitrophenacetyl (NIP) coupled to heterologous red blood cells (RBC) was enhanced by preimmunization of the spleen cell donors with the carrier RBC. The enhancement of the anti‐NIP response by carrier priming was specific and in order to stimulate an in vitro anti‐NIP response, the hapten had to be coupled to the same RBC which was used for priming.The capacity for an enhanced anti‐NIP response developed rapidly after the priming immunization, arising earlier than the anti‐carrier RBC antibody response. There was a close correlation between the priming dose of carrier RBC required to enhance the anti‐NIP response and that required to prime for an enhanced secondary in vitro RBC response. No inhibition of the anti‐NIP response of spleen cell suspensions stimulated by NIP‐SRBC was observed by the addition of excess intact or lysed SRBC.The requirement for a carrier‐specific cell which participates in the anti‐NIP response was demonstrated. The function of this cell in the anti‐NIP response was more resistant to irradiation and treatment with mitomycin C than that of the anti‐NIP precursor cell. From these and other studies in which spleen cell suspensions were treated with high specific activity [3H]d Thd it was concluded that cell division is necessary for the development of the anti‐NIP response, but that the carrier‐specific cell does not have to divide in vitro to execute its role in this response.