The Role of Interleukin-6 in Castleman Disease.

Since its discovery, improvements in treating Castleman disease and its variants have centered on interleukin-6 (IL-6). IL-6 was discovered from T-cell factors (BCDF or BSF-2), which induced B-cell maturation. Most symptoms of the plasma cell variant of Castleman disease are linked to the hyperfunction of IL-6, constitutively produced in the affected lymph nodes (1989), suggesting IL-6 is key in the pathogenesis of multicentric Castleman disease (MCD). The results of several studies have shown that most MCD symptoms and abnormal laboratory results are improved by anti-IL-6 MCD treatments, such as tocilizumab, a humanized anti-IL-6 receptor antibody, and siltuximab, an anti-IL-6 antibody.