The fluctuation of cytokine mRNA expression level of a novel T-cell-mediated immune hepatic fibrosis model in Balb/c mice / 中华传染病杂志

ABSTRACT

Objective To explore the fluctuation of cytokine mRNA expression level in a novel T-cell-mediated immune hepatic fibrosis model induced by repeatedly injections of Concanavalin A in BALB/c mice. Methods BALB/c mice were divided into different groups. Model group mice were injected weekly up to 20 weeks with Concanavalin A (15mg/kg), via retro-orbital venous plexus under ether anesthesia. Normal control group mice were treated in the same manner weekly with normal saline. Twenty-four hours after Concanavalin A challenge at 1, 5, 12 and 20 week, 8 mice from each time were killed by cervical dislocation, repectively. The livers of different group were excised and fixed in 10% formalin for HE staining and Gomori Ag staining or frozen in optimal cutting temperature (O.C.T.) media in liquid nitrogen for immunohistochemical staining for CD4 +T or CD8 +T cell. After extracting total RNA from liver tissues, IL-2, IL-4, IL-10 and transforming factor ?1 messenger RNA were amplified by reverse transcription polymerase chain reaction. PCR products were electrophoresed on agrose containing ethidium bromide and visualized under ultraviolet light. Densitometric RT-PCR data were standardized with ?-actin signals. Results The histological change of HE staining and Gomori Ag staining indicated the fibrogenesis in model group mice. Immunohistochemical staining for CD4 + or CD8 + T cell indicated that the infiltrating lymphocytes in liver parenchyma were mainly CD4 +T lymphocytes. IL-2 mRNA expression level only increased after the first injection of Concanavalin A. The expression levels of IL-4, IL-10 and transforming growth factor ?1 mRNA significantly increased over the whole experiment period as compared with control group. Conclusions Repeated administration of Concanavalin A can induce T-cell-mediated immune hepatic fibrosis model in BALB/c mice. The expression levels of IL-4, 10 and TGF-?1 increase over the whole experiment period and may play an important role in creating mouse fibrotic model.