Efficacy of thymosin α1 and interferon α for the treatment of severe acute pancreatitis in a rat model

The present study aimed to investigate the effects of treatment with thymosin alpha 1 (TA1) or interferon alpha (IFN alpha) following the establishment of severe acute pancreatitis (SAP) in rats. A total of 144 Sprague-Dawley rats were randomly divided into four groups. The rats in all four groups were celiotomized, and the rats in the control group were administered with an intravenous injection of saline. The three other groups were administered with 5% 1 ml/kg sodium taurocholate via the cholangiopancreatic duct. SAP group rats were administered with an intravenous injection of saline; TA1 group rats received 26.7 mu g/kg TA1; and interferon alpha (INF alpha) group rats received 4.0x10(5) U/kg IFN alpha. The rats were anesthetized and blood samples were collected from the animals 3, 12 and 24 h after surgery. The levels of T cell subsets, serum enzyme indicators, cytokines and procalcitonin (PCT) were measured. The general conditions of the rats were observed until sacrifice, and pancreatic and lung tissue samples were sampled for hematoxylin and eosin staining and histological scoring. The expression levels of aspartate transaminase, lactate dehydrogenase, alpha-amylase (AMY), P-type-amylase, lipase, PCT, tumor-necrosis factor a, interleukin (IL)-4, IL-5, and IL-18 in the TA1 and IFN alpha-treated rats were significantly lower, compared with those of the SAP rats within the first 24 h of model establishment (P<0.05). The TA1 and IFN alpha-treated rats exhibited significantly increased levels of CD3(+), CD4(+) and CD8(+) T cells, and an increased ratio of CD4(+)/CD8(+) cells, compared with SAP rats. Histological analysis revealed that the TA1 and IFN alpha-treated rats exhibited significantly ameliorated pancreas and lung damage, and mortality rates were reduced from 50.0% (6/12) to 25.0% (3/12) and 33.3% (4/12), respectively. The immunomodulatory agents TA1 and IFN alpha reduced acute inflammation, decreasing cell damage and enhancing immune function and survival rates in the SAP rats.