Objective To analyze the possibility of using TCR Vβsubfamily as the diagnostic in-dicators for major histocompatibility complex( MHC) deficiency-induced graft-versus-host disease( GVHD) . Methods The BALB/c mice were given 9.5 Gy (950 rad) of irradiation and transplanted with 106 of T-cell depleted (TCD) bone marrow cells from C57BL/6 and DBA/2 mice with MHC Ⅱ deficiency.Two control groups were set up accordingly by injection of TCD bone marrow cells from wild type ( WT) C57BL/6 and DBA/2 mice.Several parameters including the body weight, the GVHD clinical score and the survival time of the recipients were monitored.Flow cytometry analysis and mixed lymphocyte culture test were performed for the evaluation of autoimmune responses.Histological examination was used to analyze the severity of GVHD.Results The MHC deficiency-induced GVHD was successfully induced in the irradiated BALB/c mice receiving MHC mismatched allogeneic hematopoietic cell transplantation ( allo-HCT ) . The MHC matched DBA/2 mice with MHC deficiency could be used as the mice model of subclinical GVHD.Changes of the TCR Vβ6 were consistent with the results of histopathological examination.Conclusion Highly ex-pressed TCR Vβ6 could be used as indicators for the diagnosis of MHC deficiency-induced subclinical GVHD.

Objective To explore if bacillus bifidus relieve CPFX-induced testosterone reduction in mouse testes.Methods Twenty-four male mices were divided into 4 groups, then administered saline for 6 days (Sal6 group), CPFX for 6 days (A6 group), CPFX for 6 days followed by bifidobacteria treatment for the next 6 days (A6+P6 group), CPFX for 6 days and then saline for the next 6 days (A6+Sal6 group).We detected serum levels of testosterone by RIA, as well as levels of steroidogenic enzymes mRNA [cholesterol side-chain cleavage enzyme (P450scc) and steroidogenic acute regulatory protein (StAR)] and NF-E2-related factor2 (Nrf2) mRNA in testes by real-time PCR, Nrf2, heme oxygenase-1 (HO-1), and 4-hydroxy-2-nonenal (4-HNE) by Western blot and4-HNE by Immunohistochemistry.Results The A6 group had significantly lower serum testosterone levels compared with the Sal6 group (P<0.001), the A6+P6 group had significantly higher compared with the A6 (P<0.001) and A6+Sal6 groups (P<0.01).The A6 group had significantly lower StAR mRNA compared with the Sal6 group (P<0.001), the A6+P6 group had significantly higher level compared with the A6 (P<0.01) and A6+Sal6 groups (P<0.01).The A6 group had significantly lower P450scc mRNA as compared with the Sal6 group (P<0.001), the A6+P6 group had significantly higher compared with the A6 (P<0.001) and A6+Sal6 groups (P<0.05).The A6 group had significantly lower Nrf2 compared with the Sal6 group (P<0.001), the A6+P6 group had significantly higher compared with the A6(P<0.01) and A6+Sal6 groups (P<0.05).The A6 group higher 4-HNE expression compared with the Sal6 group, the A6+P6 group had significantly lower compared with the A6 (P<0.01) and A6+Sal6 groups (P<0.05).Conclusions Bifidobacteria the reduction of CPFX-induced testosterone reduction, and these effects may potentially explained by Nrf2 inflammatory signaling pathway.