Frequency of Intrahepatic FoxP3+ Regulatory T cells during the Natural Course of Chronic Hepatitis B: An Immunohistochemical Study Using Needle-Biopsied Liver Tissue

BACKGROUND: Regulatory T cells (Tregs) may contribute to the immunological hyporesponsiveness against hepatitis B virus (HBV), and this can result in chronic infection. Tregs suppress the T cell responses directed against HBV and they protect hepatocytes by down-regulating the immune responses that cause liver damage, but the role of Tregs has not been well characterized. METHODS: Fifty four patients were selected and classified into three groups (12 were in the immune-tolerance phase, 35 were in the immune-clearance phase and 7 were in the asymptomatic virus carrier phase). We examined the frequency of CD3+, CD4+ & CD8+ T cells and forkhead box P3 (FoxP3)+ Tregs in the needle-biopsied liver tissue by performing immunohistochemistry. RESULTS: The FoxP3+ Tregs were mainly located at the portal tracts. In the immune-clearance phase, the frequency of FoxP3+ Tregs was significantly increased compared to that of the immune-tolerance group and the asymptomatic carrier group. Increased FoxP3+ T cells were observed in the patients with a higher histologic inflammatory index. No correlation was observed among the numbers of FoxP3+ Tregs, the serum alanine aminotransferase level, detection of HBeAg and the HBV-DNA viral load. CONCLUSIONS: FoxP3+ Tregs may play important roles in suppressing the immune response to HBV and the complete elimination of HBV.

Brown Bowel Syndrome that Developed after Total Gastrectomy: A Case Report

The brown bowel syndrome (BBS) is an uncommon disorder, which is characterized by brown pigmentation of the intestine due to the accumulation of lipofuscin in the smooth muscle cells. Vitamin E deficiency has generally been considered as the cause of this malady. BBS has been reported in a wide variety of malabsorptive diseases involving the pancreas, liver and gastrointestinal tract. We report here on a case of brown bowel syndrome that occurred in a 73-year-old man who had undergone total gastrectomy 11 years ago for gastric adenocarcinoma. He has complained about intestinal obstructive symptoms for several years, and these symptoms were recently aggravated. He showed a low serum concentration of total protein, albumin and cholesterol, and he had been treated for megaloblastic anemia due to vitamin B12 and folate deficiency several months ago. The resected small bowel showed lipofuscin deposition in the muscle layer of the intestine and large vessels. The electron microscopic examination revealed multiple electron dense lipofuscin deposits with irregular shapes and sizes in the cytoplasm.