Soluble CD163, a marker of Kupffer cell activation, is related to portal hypertension in patients with liver cirrhosis

Abstract

Background Activation of Kupffer cells may be involved in the pathogenesis of portal hypertension by release of vasoconstrictive substances and fibrosis due to co-activation of hepatic stellate cells. Aim To study soluble plasma (s) CD163, a specific marker of activated macrophages, as a biomarker for portal hypertension in patients with liver cirrhosis. Methods We measured sCD163 concentration and the hepatic venous pressure gradient (HVPG) by liver vein catheterisation in 81 cirrhosis patients (Child–Pugh CP-A: n = 26, CP-B: n = 29, CP-C: n = 26) and 22 healthy subjects. We also measured their cardiac output (CO), cardiac index and systemic vascular resistance (SVR). Liver status was examined by Child–Pugh and MELD-score. Results In cirrhosis, sCD163 concentration was nearly three times higher than in controls (4.7 ± 2.5 vs. 1.6 ± 0.5 mg/L, P < 0.001). sCD163 was also higher, as measured in steps by CP-score (P < 0.001). The HVPG rose steeply to an asymptote of 22 mmHg with sCD163 up to about 5 mg/L and not to higher values with higher sCD163. In a multivariate analysis, sCD163 was the only independent predictor of the HVPG but did not predict any of the systemic circulatory findings. sCD163 > 3.95 mg/L (upper normal limit) predicted HVPG ≥ 10 mmHg with a positive predictive value of 0.99. Conclusions Circulating sCD163 originating from activated Kupffer cells is increased in cirrhosis with increasing Child–Pugh score and with increasing HVPG, and it is an independent predictor for HVPG. These findings support a primary role of macrophage activation in portal hypertension, and may indicate a target for biological intervention.