Serum LBP levels reflect the impaired synthetic capacity of the remnant liver after partial hepatectomy in rats

Abstract

Lipopolysaccharide (LPS) binding protein (LBP) is up-regulated in inflammation and infection. Its use as a biomarker of severe infection and sepsis is currently discussed controversially. Here a novel LBP-ELISA was established to assess serum LBP-levels after various degree of in a rat partial hepatectomy (PH) model. The LBP enzyme-linked immunosorbent assay (ELISA) was designed based on the binding between LPS and LBP. LPS was employed as capture molecule. An anti-LBP antibody was used as detection antibody. Serum LBP levels were measured in serum obtained 24h after 30% PH, 70% PH and 90% PH in rats using newly established LBP ELISA method. Expression of hepatic LBP mRNA was measured by real-time quantitative reverse transcription polymerase chain reaction (RT-PCR). The detection range of the ELISA was from 0.1 μg/ml to 60 μg/ml. The correlation between ELISA and western blotting was strong (r=0.885, p<0.0001). Hepatic LBP mRNA expression was upregulated after PH. Of note, elevations of serum LBP protein levels were positively correlated to the remnant liver mass (R=0.821, p<0.0001), serum albumin levels (R=0.532, p<0.05) and total protein levels(R=0.813, p<0.0001). In conclusion, we established an economic and rapid ELISA assay for rat serum LBP quantification. Our results speak against using LBP as diagnostic marker of the acute phase response after liver resection as its elevation is related to the size and thereby the synthetic capacity of the small remnant liver.