Studies of the Sensitization in Mice Induced by Cellular Fractions Containing H-2 Antigens

Summary The sensitization induced in inbred mice by the injection of antigenic fractions containing allogeneic H-2 antigens has been investigated. Fractions injected intraperitoneally led to strong sensitization which was maximal in grafts placed on the 4th day and was of short duration. Fractions injected subcutaneously sensitized less intensely. Those injected intravenously were relatively ineffective, but when given in large doses sensitized strongly. The injection of multiple small doses potentiated the response, but injection of multiple large doses led to a less intense, but more prolonged response than a single dose. Injection of the antigenic fraction in Freund9s adjuvant resulted in a loss of the ability to sensitize which may have been due to the denaturation of lipoprotein in the fraction during the emulsification step.