Hypersensitivity to Ascaris Antigens

Abstract

Summary Guinea pigs were immunized with a crude Ascaris suum extract emulsified in complete Freund's adjuvant. Anti-Ascaris antibodies were obtained from three separate serum pools as follows: 1) by precipitation with ammonium sulfate at 33% saturation and subsequent electrophoretic separation on Geon blocks; 2) by decomplementation, ammonium sulfate precipitation and subsequent specific precipitation with and dissociation from a thiolated Ascaris extract; and 3) by precipitation with ammonium sulfate only. Aliquots from all the preparations were absorbed with a rabbit anti-guinea pig 7 S γ1 serum, and antigenically pure guinea pig 7 S γ2 anti-Ascaris antibodies as well as unabsorbed controls were tested by passive cutaneous anaphylaxis (PCA) in guinea pigs. The results indicated that guinea pig 7 S γ2 anti-Ascaris antibodies were able to elicit local anaphylactic reactions of the skin. Although the reactions appeared later (1½ to 4 hr after challenge) than in the classical PCA, the possibility of a reversed passive Arthus-type reaction was ruled out.