Identification of defensin binding to C1 complement

Authors:
  • OSOded Szold
    Oded Szold
  • PPPak H. Poon
    Pak H. Poon
  • YTYiou Tseng
    Yiou Tseng

Abstract
In human serum we found strong defensin binding to the complexes of activated C1 complement (C) and C1 inhibitor (C1i). Purified C1q, activated C1 tetramer ( 2 2) and C1i did not bind defensin. When ( 2 2) was dissociated by EDTA, only the activated C1s (Cs) bound defensin. Binding of defensins to C complement represents a newly recognized bridge between the complement‐ and phagocyte‐mediated host defenses, and a potential mechanism for protecting infected tissue from cytotoxic injury by defensin.