Peptides of Myelin Basic Protein Are Encephalitogenic in Rats without the Aid of Emulsions

Abstract

Immunization with peptides is usually done with the aid of Freund's adjuvant. Using peptides derived from myelin basic protein, we show that aqueous solutions can be antigenic (encephalitogenic in this instance) in Lewis rats. The first procedure involved multiple doses of aqueous peptide, increased absorption into the lymphatic system from the peritoneal cavity in the postinflammatory state, and the use of pertussis vaccine. Three different peptides containing the major encephalitogenic site were active in this system, with the activity somewhat proportional to the size of the fragment. The second procedure, the direct delivery of peptide to lymph nodes by percutaneous inoculation, was equally successful and did not require the use of pertussis vaccine. Materials and MethodsMale Lewis rats, 8-10 weeks old, from Harlan Sprague-Dawley, Indianapolis, IN, were kept in hanging metal cages with wire mesh floors with Punna Rodent Chow 500 1 and tap water available ad libitum. PEPTIDES ARE ANTIGENIC WITHOUT EMULSIONS

Anaphylaxis Is Enhanced by Increased Absorption of Antigen in Postinflammatory State

“…Increased absorption of antigen into the lymph nodes is likely to increase the immune response. Recently, it has been found that absorption of antigens and other materials from the peritoneal cavity of rats is increased during the healing (postinflammatory) phase of a chemical peritonitis [1][2][3][4], Subsequent enhancement of the immune response has been found in studies of hemagglutinating antibodies [5] and several forms of cellmediated immunity: graft-vs.-host disease and hostvs.-graft response [2], experimental allergic encepha lomyelitis and adrenalitis [2,[6][7][8][9][10], and adjuvant arthritis [11]. In the present work, enhancement of sys temic anaphylaxis has been produced by sensitizing or challenging rats in the postinflammatory state.…”