[Isolation of immunoglobulins from the egg yolk of hens immunized with intestinal viruses].

Antibodies from the yolk of eggs of chicken immunized with enteric viruses (simian rotavirus SA 11, poliomyelitis virus type 2, and Coxsackie B2) were obtained. The time course of the emergence and amplification of antibody in the yolk was followed for several months by neutralization tests and enzyme immunoassay. The long-term persistence of a high antibody level in the yolk, the simplicity of generation of large amounts of chromatographically pure preparations, as well as specificity of chicken immunoglobulins open ways for their employment in different test systems for the detection and identification of enteric viruses.

[Persistence of the Sindbis virus in cultures producing oncornavirus].

Continuous lines were obtained from primary cultures of BALB/C mouse embryo cells which were found by electron microscope and reverse transcriptase reaction to produce permanently oncoronavirus type C after exogenous infection with Rauscher leukemia virus (RLV). Sindbis virus (SV) was inoculated into virogenic cultures 398 days after infection with RLV. The system in characterized by rapid (3-21 days) disappearance of the infectious arbovirus from the medium and the cells, long-term (over 5 months) persistence on SV noninfectious antigen and signs of stimulation of oncornavirus activity.

[Persistence of Sindbis virus in cultures either non-producing or irregularly producing oncornavirus].

Persistence of Sindbis virus (SV) was studied for 9 months in two lines of mouse cell cultures (BALB/C) in one of which the genome of endogenous ecotropic oncornaviruses was repressed. The other lines was exogenously infected at the level of plimary culture with Rauscher leukemia virus (RLV) and SV and showed gradual inhibition of oncornavirus functions. The presence of oncornavirus type C was not the necessary condition for the development of persistent SV infection, however it influenced the character of persistence.