Once activated, MK5/PRAK was reported to directly phosphorylate heat shock protein 27 (Hsp27) [91, 92], the latter having been implicated in several physiologically relevant immune-mediated inflammatory responses such as CD8+ lymphocyte subset expansion and apoptosis resistance [93] as well as in the activation of the Toll-like receptor-4 in monocyte-derived RA DCs [94]. The gene discussed is MAPKAPK5; the disease is rheumatoid arthritis.