The Anamnestic Reaction: Response of Previously Immunized Animals to Heterologous Antigens.

Abstract

University, and the Pressb ytenhn Hospital. Cole' observed, in 1904, that after an animal has been immunized subsequent injection of the same antigen causes antibodies to appear eqrlier than after the first injection. Previously immunized animals also show circulating antibodies after the injection of amounts of homologous antigen which, in animals injected for the first time, are insufficient to cause the appearance of demonstrable antibodies. A clinical counterpart of these experiments has been observed in what is called accelerated serum disease : symptoms and circulating precipitin appear earlier when a patient is treated a second time with serum.It has been observed,* too, that individuals previously vaccinated against typhoid may show a reappearance of typhoid agglutinins during the course of typhus. Bieljng3 studied this anamnestic phenomenon in rabbits, using as antigens the Shiga and His-Russel types of 23. dysenteriae and B. typlzosus. H e found that the heterologous antigen would call back, so to speak, the agglutinins for the antigen previously administered.I n subjecting the anamnestic reaction to a systematic study we have used 4 antigens sufficiently remote from each other in biological origin to exclude group reactions, A series of 18 rabbits has been studied over a period of 3% years. The antigens used were horse serum, chicken serum, crystalline egg albumin and B. typho-SW. Immunization with horse serum and chicken serum was accomplished by giving 3 intravenous injections (0.5 cc., 1.0 cc., 1.5 cc.) a t intervals of 5 days. For the egg albumin immunization, 3 intravenous injections (1.0 cc., 2.0 cc., 3.0 cc.) of a 3 per cent solution at 5 day intervals were given. Suspensions of B. typliosus a t first heat killed, and later, living organisms were injected intravenously 7 times in the course of 16 days, the number of organisms amounting to approximately 5th billion. Titrations of precipitin or agglutinin were made 5 days after the last antigen injection, and then at intervals of 7 days. Reinjection with a second antigen was not made until the antibodies produced during the previous immunization had disappeared entirely from the circulation. I t was found that rabbits previously injected with horse serum would freat GEORGETOWN UNIV MED CTR on July 15, 2015 ebm.sagepub.com Downloaded from