Active immunization with feline leukemia virus envelope glycoprotein suppresses growth of virus-induced feline sarcoma

Abstract

The efficiency was examined of immunization with feline leukemia virus glycoprotein complexes (gp85 rosettes) to protect cats against tumors induced by feline sarcoma virus (FeSV). The glycoprotein was isolated from feline leukemia virus (FeLV). Young cats were vaccinated with the purified viral glycoprotein and challenged with FeSV (FeLV). FeLV gp85 antibody levels were measured by enzyme-linked immunosorbent assay and tumor volumes were determined. In immunized animals tumor development was reduced. Gp85 antibody levels before challenge were correlated inversely with tumor size (r2 = 0.79). This method appears to be suitable for fast and efficient testing of future FeLV vaccines.

Prospect for prevention of human immunodeficiency virus infection: purified 120-kDa envelope glycoprotein induces neutralizing antibody.

“…The latter two were quite faint. This observation suggested that the radioiodinated gpl2O preparation contained partially degraded gpl2O molecules in agreement with previous o'bservations (15 (27)(28)(29)(30)(31). Extensive experience in the production of large quantities of HIV has shown that purified virion preparations contain many contaminating cellular proteins and very little gpl20.…”

Shedding and Interspecies Type Sero-reactivity of the Envelope Glycopolypeptide gp120 of the Human Immunodeficiency Virus

“…Thus neutralizing antibodies administered by serotherapy (Hunsmann et al, 1975) or induced by vaccination (Hunsmann et al, 1981) can protect animals against virus-induced Friend-erythroleukaemia and feline sarcoma (Hunsmann et al, 1983). After infection glycoproteins evoke the highest titre of antiviral antibodies (Ihle & Hanna, 1977).…”

Possible immunoenhancement of persistent viremia by feline leukemia virus envelope glycoprotein vaccines in challenge-exposure situations where whole inactivated virus vaccines were protective

“…coworkers (1975, 1981) have inm~nized mice against Friend marine leukemia virus using purified viral envelope proteins gp71 or gp85 complexes. A similar preparation, FeLV-gp85, has been used to immunize cats against Snyder-Theilen fibrosarcoma virus (ST-FeSV) induced tumors (Hunsmann et al, 1983). Feline leukemia virus-gp85 was immunogenic in cats, and inm~mized cats developed smaller tumors than non-vaccinated animals.…”