Study of infiltrating lymphocytes in cutaneous lesions of lichen planus

Objective: To investigate the role of infiltrating lymphocytes in the cutaneous lesions of lichen planus(LP).Methods: The expressions of CD3,CD4,CD8,and CD20 were detected by immunohistochemical SP method in 32 LP patients with cutaneous lesions and 30 normal subjects.Results: In the epidermis,the infiltrating lymphocytes were mainly CD3~+ and CD8~+ T cells and(CD20~+) B cells were found by chance.The predominant cells in the dermis were CD3~+,CD4~+,and CD8+ T cells.With the prolongation of the disease course,the number of infiltrating lymphocytes in the cutaneous lesions reduced(P0.01),the ratio of CD4~+ to CD8~+ T cells in the dermis decreased(P0.05),and the proportion of CD20~+ B cells increased(P0.05).The number of CD20~+ B cells markedly increased in LP patients with hyperplastic changes.Conclusion: CD8~+ T cells are associated with the cutaneous lesions of LP.Imbalance of CD4~+ and CD8~+ T cells exists in the cutaneous lesions.CD20~+ B cells may be related to the continuous immune response and excessively hyperplastic changes in the cutaneous lesions of LP.