Analysis of T cell receptor alpha-chain variable region (Vα) usage and CDR3α of T cells infiltrated into lesions of psoriasis patients

Psoriasis is a common inflammatory skin disease and is considered as T cell-mediated immune response. In this study, we analyzed T cell receptor alpha-chain variable region (TCR Vα) usage in the lesions of psoriasis patients using 5′-RACE. As the results, Vα1, -2, -7, -8, -10, -11, -12, and -23 were commonly detected in psoriatic lesions and comparison of expressions of these Vα types between psoriasis patients and healthy individuals showed that Vα1, -7, -11, and -12 were highly increased in psoriasis patients than in healthy individuals. Compared with atopy dermatitis patients, the expressions of Vα1 and Vα7 were increased in psoriasis patients. Then, to identify CDR3α of T cells infiltrated in psoriatic lesions, we examined which type of J gene segment was rearranged with Vα1 or Vα7, which the expressions was specifically increased in psoriatic lesions. The result showed that the V–J rearrangements between the examined patients were not equivalent and their frequencies were diverse, however, several common rearrangements such as Vα1–Jα13, -23, -27, or -34 and Vα7–Jα12, -33 were detected. The results in this study might provide the clue to define the characteristics of T cells associated with the pathogenesis of psoriasis.