Abstract:

Objective　To elucidate the functional status of dendritic cells (DC) in the tissue of oral squamous cell carcinoma by analyzing characteristic phenotype of them.Methods　34 specimens from oral squamous cell carcinoma cases primarily treated with surgery were selected as test group.In addition, 30 specimens of normal mucosa from oral mucocele cases were used as con- trol. Distribution of DC expressing CD1a+, HLA-DR+and CD83+in tumortissue and normal mucous membrane was observed by immunohistochemistry. The number of DC expressingthe antigens, which represented the density of DC infiltrating intotissue, was counted by microscope. The density of DC and the rate of DC expressingHLA-DR in oral carcinoma group and controlwere statis- tically compared.Results　There was no CD83+DC in all cases, but CD1a+DC was found in all samples. The density of CD1a+DC in tumortissue was significantly lowerthan that in normal mucous membrane (P<0.05). HLA-DR antigen expressed on the surface of DC in tumoral epithelium of 27-case carcinoma specimens and in normal mucous epithelium of 23 cases. The rate of HLA-DR positive expression of TIDC had no statistic significance between the two groups.Conclusion　The lower density of DC infiltrating in tumor tissue might reflect the microenviromental immunodeficiency of hosts with oral squamous cell carcinoma, and the functional mature of DC might be inhibited by the immunosuppressive action of oral squamous cell carcinoma.

Key words: dendritic cell, oral carcinoma, immunohistochemistry