Amplification of human immuno-deficiency virus production from a virus-producing cell line in culture at high cell density.

The amount of infectious virus released into the culture fluid from human immunodeficiency virus (HIV)-producing MOLT-4 cells (MOLT-4/HIV HTLV-III) was measured as a function of the culture conditions and cell density. After 3 days, the daily yield of infectious virus per cell in the fluid of non-growing cells cultured at high cell density was about 15 times higher than the accumulated yield from growing cells cultured at low cell density. SDS-PAGE analysis also showed a similar difference in the amounts of major gag protein p24.