Peritoneal macrophages are impaired in cathelicidin-deficient mice systemically challenged with Escherichia coli

Cathelicidins are small, cationic peptides produced by macrophages with protective effects against infection although their involvement in phagocytosis is not fully understood. This study demonstrates that fewer macrophages were recruited in mice genetically deficient in cathelicidin (Camp(-/-)) during acute Escherichia coli-induced peritonitis and those macrophages had impaired phagocytosis. These defects seem due to endogenous functions of murine cathelicidin (CRAMP) as phagocytosis was not improved by synthetic human cathelicidin (LL-37) in a murine phagocytic cell line. This knowledge contributes to understanding the function of cathelicidins in the recruitment and function of phagocytic cells and differential roles between endogenous and exogenous cathelicidins.

Automated summary

This study showed that mice deficient in Cathelicidin had fewer recruited macrophages with impaired phagocytosis during acute Escherichia coli-induced peritonitis, which was attributed to endogenous functions of murine Cathelicidin CRAMP. Synthetic human Cathelicidin LL-37 did not improve phagocytosis in a murine phagocytic cell line, highlighting the differential roles between endogenous and exogenous Cathelicidins.