Antibodies reacting with salmon and human protamines in sera from infertile men and from vasectomized men and monkeys

A micro-complement fixation test was modified for the detection of low-titred antibodies to protamines. Specific immunological reactions with salmon protamine were found with some sera obtained from infertile men and vasectomized men and monkeys. The possibilities that allergic reactions, observed in patients receiving salmon protamine, result from immunity to the fish protamine and from immunological cross-reaction between human and salmon protamines (in cases where auto-immunity to human protamine has developed prior to the administration of fish protamine) are discussed.