[Human interleukin-2 gene transfer and expression inhibits hepatitis B virus surface antigen expression and enhances LAK activity of peripheral blood mononuclear cells of normal adults].

Using molecular cloning techniques, we constructed and transfected human interleukin-2 gene expressive retroviral vector into a packaging cell line PA317. Geneticin resistant cell clones were identified and pseudoviral particles titred as 3.75 x 10(6)CFU/ml in their culture supernatants. Human interleukin-2 expression level was 5.71IU/ml for NIH3T3, 6IU/ml for both 2. 2. 15 and peripheral blood mononuclear cells after infection with pseudoviral particles with 8 of multiplicity of infection (M. O. I). Low level interleukin-2 expression potentially inhibited hepatitis B virus surface antigens expression of 2. 2. 15 cell line and enhanced cytotoxicity of peripheral blood mononuclear cells against K562 and Raji as target cells, but neither pseudoviral particles without interleukin-2 cDNA nor reccombinant interleukin-2 at 6 IU/ml. These results indicated that retroviral vector-packaging cell line can efficiently transfer and express interleukin-2 cDNA in human somatic cells and low level expression of interleukin-2 potentially inhibits hepatitis B virus surface antigens expression and enhances LAK activity of peripheral blood mononuclear cells of normal persons.