Incorporation of bacteriophage DNA into the genome of cultured human lymphocytes.

After exposure of phytohemagglutinin-stimulated human lymphocytes to high doses of tritiated-thymidine labelled phi X-174 or T2 bacteriophage, label from the phage genome became incorporated into lymphocyte DNA. Exposure to bacteriophage DNA, whether biologically active, inactive, or fragmented, had a depressive effect on lymphocyte DNA replication. Incorporation of label from phage DNA into the lymphocyte DNA, however, was maximum for biologically active phage.