Abstract: Objective To investigate the change of peripheral blood lymphocytes of hay fever and its relationship with different stage of pathogenesis. Methods The peripheral blood cell counts and lymphocyte subsets of 20 cases hay fever patients in onset and non-onset period were determined by hematology analyzer and flow cytometry. Results The level of eosinophils, basophils, CD8+CD28+T cells and CD8+CD38+T cells was significantly higher (P <0.05 ), NK cells was lower (P <0.05) , and B lymphocytes, T lymphocytes, CD4+T cells, CD8+T cells and CD4+CD28+T cells had no significant change in peripheral blood of hay fever in onset period compared with those in non-onset period. Conclusions Hay fever patients’CD8+CD28+ and CD8+CD38+T cell might be in a state of immune activation in onset period, play an important role in allergic inflammation.

Key words: hay fever, onset, non-onset, lymphocyte subsets