EBV-infected B cells in infectious mononucleosis: Viral strategies for spreading in the B cell compartment and establishing latency

Infection of humans with Epstein-Barr virus (EBV) may cause infectious mono nucleosis (IM). Analysis of single EBV-infected cells from tonsils of IM pa tients for rearranged immunoglobulin genes revealed two strategies of EBV f or rapid and massive spread in the B cell compartment: the direct infection of many naive as well as memory and/or germinal center B cells and the exp ansion of the latter cells to large clones. In IM, the generation of virus- harboring memory B cells from naive B cells passing through a germinal cent er reaction likely plays no role. Members of clones can show distinct morph ologies and likely also EBV gene expression patterns, and this ability impl ies a mechanism by which EBV-harboring cells can evade immune surveillance and establish a pool of persisting EBV-infected B cells.