Immune responses in vitro. VI. Genetic control of the in vivo-in vitro discrepancies in 19S antibody synthesis.

The finding that the relationship of the in vitro and in vivo responses of different strains of mice is under genetic control indicates that at least two mechanisms must operate under in vivo conditions to control 19S antibody synthesis. One is involved in the termination of 19S antibody synthesis; the other has a regulatory role on the magnitude of the response. In light of these findings, various concepts based on other genetically controlled immune responses and on the limiting dilution technique should be reassessed. Furthermore, the suppressive in vivo mechanism may be an important type of control in the resistance or susceptibility to the establishment or maintainance of neoplasms.