CD30 and type 2 T helper (Th2) responses

CD30 is one of the members of the tumor necrosis factor receptor superfamily, originally described as a marker of Reed‐Sternberg and Hodgkin's cells in Hodgkin's lymphoma. CD30 appears to be preferentially expressed on, and its soluble form (sCD30) released by, CD4 + and CD8 + T cell clones capable of producing T helper 2 (Th2)‐type cytokines. In nonneoplastic conditions, CD30 + T cells are barely detectable in vivo; however, a few allergen‐specific CD4 + CD30 + T cells inducible to the production of Th2‐type cytokines could be sorted out from the circulation of allergic subjects after allergen exposure. Moreover, high numbers of CD30 + T cells were found in the lymph node of a patient suffering from Omenn's syndrome, a rare congenital Th2‐mediated immunodeficiency disorder. More importantly, high serum levels of sCD30 were observed in some conditions in which a pathogenetic role for Th2 cells has been suggested, such as Omenn's syndrome, atopy, systemic lupus erythematosus, and after infection with measles virus or human immunodeficiency virus. Thus, detection of CD30 + T cells and/or of increased levels of sCD30 may reflect the presence of immune responses or immune alterations characterized by the prevalent activation of Th2‐like cells. J. Leukoc. Biol. 57: 726‐730; 1995.