Immunological memory for HIV-1 induced in rabbits by immune poly(A)+ RNA

ABSTRACT

New Zealand rabbits were used to demonstrate the in vitro and in vivo transfer of reactivity, including immunological memory, to a synthetic peptide corresponding to residues 586-606 of the gp-160 protein of human immunodeficiency virus (HIV-1). The transfers were mediated by immune poly (A)+ RNA from lymphoid organs(spleen and mesenteric nodules) harvested after immunization of a sheep with the peptide (8subcutaneous injections plus glucan and complete Freund's adjuvant using a total of 1750 *g peptide). Immunological reactivity was detected by the leukocyte adherence inhibition (LAI) test for cellular immunity. A dose of 150 *g poly (A) RNA ml-1 10 *******7 leukocytes -1 or 2.0 *g poly(A)+ RNA ml-1 10*******7 leukocytes-1 was used for in vitro transfer. For in vivo transfer the recipient rabbits received 3,000 *g poly(A)- RNA or 20*g poly(A)+ RNA. The mean non-adherence index(NAI) obtained in vitro was 10ñ7 for leukocytes treated with poly (A)- RNA and 60ñ10 leukocytes treated with poly(A)+ RNA. The poly(A)+ RNA fravction induced a primary-like response and memory cells in vivo. The poly (A)- RNA fraction had no effect. Since sheep are refractory to, and rabbits are sensitive to HIV-1, we suggest the use of this animal model for testing the immunomodulating effect of anti-HIV-1 immune poly(A)+ RNA