TNFRSF12A mRNA Expression and distribution of TNFRSF12A+ cells in rat liver during thioacetamide-induced fibrogenesis

Abstract

TNFRSF12AmRNA expression and distribution of TNFRSF12A+ cells were studied in detail for the first time at different stages of fibrosis in rat liver. Under physiological conditions, the expression level ofTNFRSF12AmRNA was 0.224 (95% CI: 0.170–0.277). At the same time, cells expressing theTNFRSF12Amarker were practically absent. In bridging fibrosis, the first peak ofTNFRSF12AmRNA growth (p=0.000) and an increase in the area of TNFRSF12A+ cells (p=0.000) was established. The second peak (p=0.000) was detected during the process of transformation of fibrosis into cirrhosis. At the stage of incomplete cirrhosis, a sharp drop was noted. A subsequent increase in the expression ofTNFRSF12AmRNA and the area of TNFRSF12A+ cells was observed from the stage of significant cirrhosis. Immunohistochemical method revealed two groups of TNFRSF12A+ cells. In the sinusoidal capillaries TNFRSF12A+, the cells had a shape close to flat and resembled endotheliocytes, while in the fibrous connective tissue they were rounded. The number ofα-SMA+ cells increased gradually (p=0.000) before the onset of significant cirrhosis, and then there was a sharp increase (p=0.000).