Review article: Medical intelligence | Published 20 July 2010, doi:10.4414/smw.2010.13042 Cite this as: Swiss Med Wkly. 2010;140:w13042 Cathepsins and their involvement in immune responses Sébastien Conus, Hans-Uwe Simon Institute of Pharmacology, University of Bern, Bern, Switzerland Correspondence to: cleaving proteases (= caspases) which cleave a wide range Sébastien Conus Ph.D. of cellular substrates [5]. Institute of Pharmacology Besides caspases, cathepsins have recently been shown University of Bern to be associated with cell death regulation [6–12] and vari- Friedbühlstrasse 49 3010 Bern ous other physiological and pathological processes, such as Switzerland maturation of the MHC class II complex, bone remodel-
[email protected] ling, keratinocyte differentiation, tumour progression and metastasis, rheumatoid arthritis and osteoarthritis, as well Summary as atherosclerosis [13, 14] (table 1). Thus, cathepsins ap- pear to play a significant role in immune responses. In this The immune system is composed of an enormous variety of review we discuss recent advances addressing the role of cells and molecules that generate a collective and coordin- lysosomal proteases in the diverse aspects of the immune ated response on exposure to foreign antigens, called the response, and also the involvement of cathepsins in the immune response. Within the immune response, endo-lyso- pathogenesis of diseases in which these proteases seem not somal proteases play a key role. In this review we cover to be properly under control. specific roles of cathepsins in innate and adaptive immu- nity, as well as their implication in the pathogenesis of sev- The cathepsin family eral diseases. Lysosomes are membrane-bound organelles which repres- Key words: adaptive and innate immunity; apoptosis; ent the main degradative compartment in eukaryotic cells.