Abstract: Abstract Objective:To analyze the difference in total T cell, CD8+T cell and HLA-DR expression on CD8+T cell of peripheral blood in 27 children with acute EB virus infection and 7 children with chronic EB virus infection.Results: Total T cell , CD8+T cell and CD8+/HLA-DR+ cell in acute infected group were higher than chronic infected group and control(p<0.01);T cell was lower than control and CD8+/HLA-DR+ cell was higher than control in chronic infected group(p<0.01).Conclusion: There were significant difference in total T cell, CD8+T cell and HLA-DR expression on CD8+T cell of peripheral blood between acute and chronic EB virus infection ,It was low activated level of CD8+T cell in chronic EB virus infection.It can evaluated cellular immune function to detecte CD8+T cell activation for EB virus infected children.

Key words: EB virus, CD8+T cell, HLA-DR, children