Background: Hodgkin's lymphoma (HL) is characterised by an ineffective immune response that is predominantly mediated by CD4+ T-cells.
Aims: To analyse the expression of the key regulatory T-cell transcription factors (TFs) in the T-cells of HL involved tissues in order to assess the nature of the T(H) immune response in HL.
Methods and results: By immunohistochemistry, GATA3 was strongly and T-bet exclusively expressed in a subset of interfollicular lymphocytes in the reactive lymphoid tissues. In classical HL (CHL), which is generally located in the interfollicular zones, a predominance of T-bet+ T-cells and lesser amounts of GATA3+ and c-Maf+ T-cells was found, concordant with the pattern of the normal interfollicular compartment. In reactive lymphoid tissues, c-Maf was observed mostly in T-lymphocytes within the germinal centres (GCs). Nodular lymphocyte predominance type of Hodgkin's lymphoma (NLPHL) and progressively transformed germinal centres cases, showed a majority of c-Maf+ T-cells, consistent with the pattern in normal GCs. NLPHL cases uniformly showed c-Maf+/CD57+ T-cell rosettes around the neoplastic cells; these rosettes were absent in "paragranuloma-type" T-cell/histiocyte rich B-cell lymphoma.
Conclusions: T-cell TF expression profiles of the reactive T-cells in both subtypes of HL are in accordance with the expression profile observed in the distinct lymphoid compartments.