Abstract: The present invention provides novel compositions and methods useful in the, modulation or selective suppression of host immune responses to an immunogen of interest, particularly exogenous antigens and allergens such as urushiol, the active plant component causing poison ivy/oak contact sensitivity. The subject compositions are antibody molecules of either Ab.sub.1 or Ab.sub.2 (anti-idiotypic) reactivity with respect to the sensitizing antigen. Other compositions include specific T cell receptor (TCR) molecules either as T cell clones or hybridomas or as TCR preparations. Immunogenic peptides corresponding to some or all of the complementary determining regions or hyper-variable regions of the TCR are also employed. Such compositions suppress host immune responses to antigen by a variety of pathways including anti-idiotypic interactions with cells involved in antigen processing and stimulation of the immune network.

Abstract: The present invention provides novel methods for the treatment of retroviral infection, particularly HIV disease. According to the present invention, human HIV infected hosts were selected who had been on a stable dose of an anti-retroviral agent, such as zidovudine, for up to two years prior to administration of the ribosomal inhibiting protein trichosanthin, and who had failed anti-retroviral therapy, as manifest by decrease in CD4+ cells on at least two serial measurements, or loss of over 50 CD4+ cells/mm.sup.3 /year. These patients remained on the same dose of anti-retroviral agent (AZT or ddI) and received trichosanthin, 1.2 mg weekly, then monthly. A significant number of patients demonstrated improved CD4+ cell counts following administration of trichosanthin as compared to CD4+ cell counts prior to adminstration of the drug.