NC37-R1 Epstein-Barr virus (EBV): a possible recombinant between intracellular NC37 viral DNA and superinfecting P3HR-1 EBV.

The NC37-R1 cell line, established after transformation of human cord blood lymphocytes with Epstein-Barr virus (EBV) recovered from P3HR-1 superinfected NC37 cells, spontaneously produces viral particles with transforming but without early antigen-inducing properties. Progeny virus of NC37-R1 has retained its biological characteristics of spontaneous virus release and transformation up to four cycles of transformation at present. Analysis of purified NC37-R1 virion DNA, after cleavage with restriction endonuclease Hind III and comparison of its fragments with P3HR-1 EBV as well as intracellular NC37 viral DNA using the blot hybridization technique, suggests that NC37-R1 originates from a recombination between superinfecting P3HR-1 and endogenous NC37 EBV DNA.