Cell-density-dependence for growth in agarose of two human lymphoma lines and its decrease after Epstein-Barr virus conversion.

We have compared the growth in agarose medium of two EBV-negative Burkitt lymphoma lines, BJAB and Ramos, and that of their EBV-converted derivatives. Optimal conditions for growth in agarose medium are described. The original EBV-negative lines can grow in agarose to a high efficiency, provided a critical level of cell concentration is attained. Below this level, there is no growth at all. EBV-converted sublines form colonies at a much lower cell concentration, and their maximal plating efficiency is higher. These differences may be related to a super-transformation state induced in these cells by EBV.