CD14 Expression in the First 24h of Sepsis: Effect of −260C>T CD14 SNP

Abstract

Sepsis is defined as systemic inflammation caused by infection. The membrane bound CD14 (mCD14) or the soluble form (sCD14) play a crucial role facing Gram-negative and Gram-positive sepsis since they are pattern recognition receptors of the innate immune response enabling cells to produce inflammatory cytokines against bacterial infections. A −260C>T single nucleotide polymorphism (SNP) was detected in the promoter modulating the CD14 gene expression. We hypothesized that the CD14 expression depends of the genetic inheritance of −260C>T CD14 SNP and it is modulated by sepsis condition. We investigated human CD14 expression on early sepsis diagnosis (in vivo) and after LPS stimulation (in vitro), and determined the −260C>T CD14 SNP. We found that TT homozygotes showed higher mCD14 density (p = 0.0207), but not different sCD14 levels when compared to the CT+CC genotypes. Monocyte mCD14 density and sCD14 serum levels in our sample of early 14 septic patients were significantly higher than normal 30 controls (p<0.0001). Our results suggest that the −260TT CD14 genotype is associated with higher monocyte mCD14, but not sCD14 expression, and that in the first 24 h after sepsis diagnosis, both monocyte mCD14 density and sCD14 levels are elevated, similarly to what is observed in vitro upon challenge with LPS.