Calprotectin S100A9 calcium-binding loops I and II are essential for keratinocyte resistance to bacterial invasion.

ABSTRACT: Epithelial cells expressing calprotectin, a heterodimer of S100A8 and S100A9 proteins, are more resistant to bacterial invasion. To determine structural motifs that affect resistance to bacterial invasion, mutations were constructed in S100A9 targeting the calcium-binding loops I and II (E36Q, E78Q, E36Q,E78Q) and the C terminus (S100A9(1-99) and S100A9(1-112)), which contains putative antimicrobial zinc-binding and phosphorylation sites. The S100A8 and mutated S100A9 encoding plasmids were transfected into calprotectin-negative KB carcinoma cells. All transfected cells (except KB-sham) expressed 27E10-reactive heterodimers. In bacterial invasion assays with Listeria monocytogenes and Salmonella enterica serovar Typhimurium (Salmonella typhimurium), cell lines expressing S100A8 in complex

SUBMITTER: Champaiboon C 

PROVIDER: S-EPMC2652321 | biostudies-literature | 2009 Mar

REPOSITORIES: biostudies-literature