Relationship between Epstein-Barr virus (EBV)-production and the loss of the EBV receptor/complement receptor complex in a series of sublines derived from the same original Burkitt's lymphoma

Virus production, EBV (P3HR-1 substrain) superinfectability, IdUrd inducibility, EBV receptor and complement (C3) receptor expression were assessed in two independently maintained jijoye lines, the derived P3HR-1 clone that releases a growth inhibitory and cytopathic, non-transforming viral mutant, and in non-producer sublines derived from the P3HR-1 line by the spontaneous cessation of virus production. Both jijoye lines were superinfectable, inducible, and carried EBV and C3 receptors. Virus-producing P3HR-1 cells and recently derived non-producer sublines lacked EBV-receptors and C3 receptors, could not be superinfected, but were IdUrd inducible. Two long-passaged, non-producer sublines of P3HR-1 reexpressed EBV and C3 receptors to an equal degree (different in the two sublines). EBV-superinfectability became partially reestablished in the subline with the higher expression of EBV and C3 receptors. These findings support the hypothesis that the EBV-receptor/C3 receptor negativity of the producer P3HR-1 sublines and their recent non-producer derivatives is due to negative selection by the growth-inhibitory, cytopathic P3HR-1 virus variant. The closely linked disappearance and reappearance of EBV-receptors and complement receptors gives further support to the idea that these two receptors are either identical or closely linked constituents of the cell membrane.

Antigen-inducing ability of herpesvirus papio in human and baboon lymphoma lines, compared to Epstein-Barr virus

Herpesvirus papio(HVP)-carrying baboon lymphoblastoid lines do not express a nuclear antigen like the Epstein-Barr virus(EBV)-determined nuclear antigen (EBNA), as judged by in situ anticomplement fluorescence staining, although the carry multiple viral genomes and, in the case of producerlines, early antigen (EA) and viral capsid antigen (VCA) that cross-react with the corresponding human EBV-determined antigens. To test whether the lack of in situ nuclear antigen expression is a property innate to the baboon virus or the baboon cell, nonproducer HVP-carrying baboon lymphoid cells of the 26 CB-1 line were superinfected with two human EBV strains. B95-8-derived EBV induced brilliant EBNA staining, proving that the baboon lymphoid cell was competent to synthesize EBNA. In the mirror experiment, HVP derived from the 9B or the 18C baboon line was added to the EBV-carrying Raji line, the EBV-negative Ramos and BJAB lines and the HVP-carrying nonproducer 26 CB-1 line, respectively. HVP induced EA and VCA in Raji, and EA in BJAB and 26 CB-1. EBNA was not induced in any of the three EBNA-negative lines, BJAB, Ramos and 26 CB-1. It is concluded that the lack of in situ nuclear staining in HVP-carrying baboon lines is a HVP-associated property and is not due to any innate inability of the baboon lymphoid cell to synthesize an antigen of the EBNA type.