Protection against ricin intoxication in vivo by anti-idiotype vaccination.
A BALB/c murine anti-ricin monoclonal antibody (mAb BG11-G2, IgG1K), was recently isolated and shown to passively protect syngeneic mice against ricin intoxication in vivo. New Zealand White rabbit polyclonal anti-idiotype (anti-Id) antibodies were raised to BG11-G2 anti-ricin mAb, and rendered specific by repeated absorption over agarose normal mouse immunoglobulin (Ig). The absorbed rabbit anti-Id antibodies lost reactivity to normal mouse Ig and to a BALB/c anti-T-2 mycotoxin IgG1K mAb (HD11), but remained reactive with BG11-G2 anti-ricin mAb. The rabbit anti-Id inhibited the binding of BG11-G2 mAb to ricin-coated wells, and elicited a specific and protective anti-ricin antibody response in naive BALB/c mice. Whereas all mice vaccinated with a control rabbit anti-Id antibody preparation died from in vivo ricin challenges, mice immunized with the rabbit anti-Id specific for BG11-G2 mAb were protected to various degrees. All mice vaccinated with rabbit anti-Id to BG11-G2 and challenged with ricin doses of 35 and 50 micrograms kg-1 body weight died from the challenge; however, a delay in the elapsed time between ricin administration and death was observed in these mice as compared to that of the control anti-Id-immune mice. Five of seven mice vaccinated with the rabbit anti-Id to BG11-G2 and subsequently challenged in vivo with a ricin dose of 20 micrograms kg-1 body weight survived the lethal in vivo ricin challenge, whereas all the control mice died.(ABSTRACT TRUNCATED AT 250 WORDS)
Chanh
T C
TC
Department of Virology and Immunology, Southwest Foundation for Biomedical Research, San Antonio, TX 78228, USA.
Hewetson
J F
JF
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000276:immunology / Q000627:therapeutic use*; D000911:Antibodies, Monoclonal / Q000276:immunology / Q000627:therapeutic use*; D000917:Antibody Formation; D000918:Antibody Specificity; D005260:Female; D007074:Immunoglobulin G / Q000494:pharmacology; D051379:Mice; D008807:Mice, Inbred BALB C; D011041:Poisoning / Q000517:prevention & control; D011817:Rabbits; D012276:Ricin / Q000276:immunology* / Q000506:poisoning* / Q000633:toxicity; D014611:Vaccination
D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D007074:Immunoglobulin G; D012276:Ricin