Immortalization of human lymphocytes by co-cultivation with lethally irradiated autologous T-cell lines harbouring human T-cell leukaemia virus-I.

Human adult peripheral blood lymphocytes were successfully immortalized by co-cultivation with irradiated autologous and homologous T-cell lines harbouring human T-cell leukaemia virus-I (HTLV-I). The efficiency of transformation was the same in both cases. The participation of alloantigen stimulation in co-cultivation procedures is discussed, and it is stressed that factors other than alloantigen stimulation might be required for the efficient immortalization of human T-lymphocytes in vitro by HTLV.