Bacterial antigen induced release of soluble vascular endothelial growth factor (VEGF) and VEGFR1 before and after surgery.

ABSTRACT

OBJECTIVE: The influence of surgery on release of soluble vascular endothelial growth factor (sVEGF) and the soluble inhibitory receptor (sVEGFR1) is unknown. The effect of major and minor surgery on variations in sVEGF and sVEGFR1 concentrations in vivo was studied, and on bacterial antigen-induced release of sVEGF and sVEGFR1 from whole blood in vitro. MATERIAL AND METHODS: Sixty-one patients with abdominal diseases undergoing five different surgical procedures were included in the study. Blood samples were drawn from patients before and after the operation. White blood cells and platelets were counted, and plasma sVEGF and sVEGFR1 were determined. Whole blood from each blood sample was stimulated in vitro with bacteria-derived antigens (lipopolysaccharides or protein A) and sVEGF and sVEGFR1 levels were subsequently determined in the supernatants. RESULTS: Neither sVEGF nor sVEGFR1 concentrations in plasma changed during surgery. In vitro stimulation of blood samples with bacteria-derived antigens resulted in a significant increase in sVEGF (p < 0.0001) and a less pronounced but still significant increase in sVEGFR1 (p < 0.01). Bacterial antigen-induced release of sVEGF correlated significantly with neutrophil cell counts (0.53 < r < 0.78; p < 0.0001). Bacterial antigen-induced sVEGFR1 release did not correlate with cell counts. CONCLUSIONS: Plasma sVEGF and sVEGFR1 concentrations did not change during surgery. In vitro bacterial stimulation led to increased release of sVEGF, which was not compensated for by an equivalent increase in sVEGFR1. There was a positive impact of major abdominal surgery on release of sVEGF. The bacterial antigen-induced changes in sVEGF may be related to the number of circulating neutrophils.