Analysis of TCR Vβ subfamily for the diagnosis of MHC deficiency-induced subclinical graft-versus-host disease
Objective 
To analyze the possibility of using TCR Vβ subfamily as the diagnostic indicators 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 expressed TCR Vβ6 could be used as indicators for the diagnosis of MHC deficiency-induced subclinical GVHD. 
 
 
Key words: 
Graft-versus-host disease; TCR Vβ subfamily; Major histocompatibility complex; Clone deletion; Animal model