Raising of antisera to protein hormones without using Freund's adjuvant

A new method has been developed to produce antiserum to protein hormones without the use of Freund's complete adjuvant. Antiserum to human chorionic gonadotropin (hCG) was elicited by injecting rabbits with 6 subcutaneous injections of sheep red blood cells (SRBC) coated with hCG. The antiserum produced was observed to be both serologically and biologically active. A small quantity of the hormone (15--20 IU/injection) sufficed to produce hyperimmune sera. This could ensure an overall economy if large amounts of the antisera are required for clinical and diagnostic purposes.