[Seroepidemiological characterization of virus hepatitis in the Republic of Armenia].

The survey of the population immunological structure with respect to parenteral hepatitis showed awide circulation of hepatitis B (HB) and hepatitis C (HC) viruses among the adult population of Armenia. During the 5 year period of observation the number of persons having antibodies to HC virus increased 2.7-fold.

[Experiment in infecting the green monkey Cercopithecus aethiops with a leukocyte virus isolated in hepatitis A].

The virus isolated in hepatitis A had been previously shown to passage in primary phytohemagglutinin-stimulated leukocyte cultures. The virus designated as leukocyte hepatitis virus (LHV) causes chromosome aberrations in the infected cultures. Some physico-chemical properties of LHV and its capacity for reproduction in other cell systems were studied.

[Chronic tick-bone encephalitis virus infection in continuous human lymphocyte lines studied by molecular hybridization].

Chronic infection with tick-borne encephalitis virus (Sophyin strain) has been established in continuous lines of human lymphocytes (of T- and B-origin). In 3 lines under study, the cultured virus at the level of the 15th passage had a titre of 7.22-8.

[Modeling chronic infection in a T-lymphocyte-Venezuelan equine encephalomyelitis virus system].

A model of chronic infection in the system of T-lymphocyte--VEE virus was made. Production of infectious VEE (up to 6.0 lg PFU/ml), tissue culture interferon levels (less than 10 units/ml), accumulation of virus-specific antigen in chronically infected continuous human T-lymphocytes (78%) were studied.

[Use of continuous human lymphoblastoid cell lines (T- and B-origin) to produce persistent tick-borne encephalitis virus and Venezuelan equine encephalomyelitis virus infections].

Persistent infection with tick-borne encephalitis virus (TBE) was established in experimentally infected continuous lymphoblastoid human cell lines Raji, L-101 (of B-origin) and 1387 (T-origin) and with Venezuelan equine encephalomyelitis (VEE) virus in Raji and 1387 lines. The persistently infected lines produced infectious virus, the cells showed specific fluorescence in immunofluorescent tests, and electron microscopic examinations revealed TBE and VEE virions in sections.

[Alphavirus reproduction in cultures of transplantable human lymphoblastoid cells during persistent infections].

The results of virological investigations of alphavirus persistence in human B-cell lines Raji and L-101 are presented. The formation of persisting infection was shown to depend both on the cell line and on the virus type. Productive persistent infection of Raji cells with Venezuelan equine encephalitis virus was followed for 11 months.