Latently infected B cells are a major reservoir for KSHV in the body, and the virus is believed to be shed from tonsillar B-cells via saliva. Paradoxically, while several "irrelevant cell lines (non-B cell, non-human) are permissive for in vitro KSHV infection, human B-cell lines and primary-B cells are notoriously refractory to infection. By conducting a strategic search of B lymphomas, we previously identified a novel B-cell line (designated B3) that is susceptible to KSHV infection. Studies with a recombinant KSHV encoding EFGP and puromycin resistance under constitutive cellular promoters, we demonstrated 20% infection of B3 cells based on measurements of EGFP expression, viral DNA replication, latency-associated transcription, and viral protein synthesis. Lytic phase and low level replication could be induced by HDAC inhibitors. Puromycin selection yielded cultures in which the entire population was KSHV infected (EGFP-positive), and lytic replication could be induced by antibody crosslinking of the B cell receptor. Studies of entry have focused on the role of candidate KSHV receptors, and on the importance of virus interaction with surface proteoglycans. As a complementary approach, we have generated a panel of mAbs against KSHV glycoprotein H (gH), for studies on effects on KSHV infection of B cells and other target cell types, as well as effects on interactions with specific candidate KSHV receptors.
|Dollery, Stephen J; Santiago-Crespo, Rey J; Kardava, Lela et al. (2014) Efficient infection of a human B cell line with cell-free Kaposi's sarcoma-associated herpesvirus. J Virol 88:1748-57|