Expression of the Ig-associated heterodimer (mb-1 and B29) in Hodgkin's disease

Eighty-three cases of Hodgkin's disease were studied immunocytochemically for the presence of the Ig associated heterodimer (mb-1 and B29) which is believed to be a specific pan B-cell marker. These results were compared with those achieved using other B-cell markers against CD19, CD20 and CD22. Although a small number of cases of nodular sclerosis and mixed cellularity subtype showed positivity for CD19, CD20 or CD22, no case showed any reactivity with antibodies against mb-1 or B29. This contrasted markedly with the cases of lymphocyte predominance where all seven cases expressed one or more of the B-cell antigens, with six cases being positive for mb-1. These results confirm previous studies that have suggested lymphocyte-predominance Hodgkin's disease is of B-cell origin and different from the other subtypes. However, they do not provide support for the thesis that these other subtypes may also have a B-cell origin, albeit with a different phenotype to lymphocyte predominance.