BOB-1 (B-cell specific octamer binding
protein-1) protein is a B-lymphocyte-specific transcriptional coactivator. It
interacts with Oct-1 and Oct-2 transcription factors. BOB-1 and Oct-2 play
essential roles in germinal center formation and immunoglobulin production.
BOB-1 has been reported to be detectable in all B-cell populations found in
reactive lymphoid tissues, the strongest expression being found in germinal
center Bcells and plasma cells. BOB-1 and Oct-2 are most useful for the
B-lineage determination of CD20-plasmablastic, or primary effusion subtypes of
diffuse large Bcell lymphoma (DLBCL). Other studies have shown BOB.1, CD79a and
Cyclin E are the most appropriate markers to discriminate classical Hodgkin’s
lymphoma from primary mediastinal large B-cell lymphoma. The strong nuclear
expression of BOB-1 and Oct-2 by germinal center derived lymphomas makes these
antibodies a novel class of broad spectrum B-lineage immunohistochemical markers
in the differential diagnosis of lymphomas.