Aim: It has been reported that host defense responses, such as phagocytic function of neutrophils and natural killer (NK) cell activity of lymphocytes, are impaired in cirrhotic patients. The aim of the present study was to examine the effects of oral supplementation of branched-chain amino acids (BCAA) on host defense mechanisms in peripheral blood of patients with decompensated cirrhosis.
Methods: Ten patients with decompensated cirrhosis received 12 g BCAA daily for 3 months. Phagocytic function of neutrophils and NK activity of lymphocytes as well as serum albumin levels and Fisher's ratios were determined before and at 1 and 3 months of BCAA supplementation. For quantification of phagocytic function, fluorescent intensities of cells in the neutrophil region in the cytogram were determined by flow cytometry after incubation of whole blood with fluorescent microspheres. NK activity was estimated by 51Cr release assay using K-562 cell line as target cells.
Results: Phagocytic function of neutrophils was significantly improved by 3-month BCAA supplementation (P < 0.01). Thechanges of NK activity were also significant at 3 months of supplementation compared with before supplementation (P < 0.01). Fisher's ratios were significantly increased at 3 months of BCAA supplementation compared with those before oral supplementation (P < 0.05), although the changes of serum albumin level were not statistically significant.
Conclusions: BCAA oral supplementation improved phagocytic function of neutrophils and NK activity of lymphocytes in cirrhotic patients. BCAA supplementation may reduce the risk of bacterial and viral infection in patients with decompensated cirrhosis.