Low clinical penetrance of mannose-binding lectin-associated serine protease 2 deficiency.

摘要

To the Editor:The complement system plays a key role in innate immune responses. Complement deficiencies of early classical pathway (CP) or alternative pathway (AP) components are associated with increased susceptibility to pyogenic infections with encapsulated bacteria and to autoimmune and inflammatory disorders, particularly systemic lupus erythematosus (SLE). A third pathway, the lectin pathway (LP), is triggered by binding of mannose-binding lectin (MBL) or other lectins, such as L-ficolins and H-ficolins, to specific pathogen-associated molecular patterns on microbial surfaces. Thereafter, the MBL-associated serine protease 2 (MASP-2) cleaves complement factors C4 and C2, generating the C3 convertase, C4bC2b.