Scabies Mite Inactivated Serine Protease Paralogs Inhibit the Human Complement System

摘要: Infestation of skin by the parasitic itch mite Sarcoptes scabiei afflicts 300 million people worldwide and there is a need for novel efficient therapies. We have previously identified multigene family serine proteases comprising multiple catalytically inactive members (scabies mite-inactivated protease paralogs (SMIPPs)), which are secreted into gut S. scabiei. SMIPPs located in feces excreted upper epidermis. Scabies mites feed on epidermal protein, including host plasma; consequently, they exposed to defense mechanisms both internally externally. found that two recombinantly expressed inhibited all three pathways human complement system. Both exerted their inhibitory action due binding molecules involved different initiate complement: C1q, mannose-binding lectin, properdin. bound stalk domains possibly displacing or inhibiting C1r/C1s, associated with same domain. Furthermore, we properdin resulted prevention assembly alternative pathway convertases. However, were not able dissociate already formed Immunohistochemical staining demonstrated presence C1q scabies burrows. propose minimize complement-mediated damage thus create favorable environment mites.