ABSTRACT
<p><b>OBJECTIVE</b>To explore the relationship between CD8+ T-cell CD28 molecular expression in peripheral blood and TCM type in patients with chronic aplastic anemia (CAA).</p><p><b>METHODS</b>Using flow cytometry to detect the CD28 expression in 45 in-patients or out-patients and 24 healthy subjects for control. And the relation with TCM type was analyzed from the immunological aspect.</p><p><b>RESULTS</b>(1) The levels of CD8, CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- were all higher in the CAA patients than those in the healthy subjects (P < 0.05 or P < 0.01). (2) The levels of CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- were all higher in the CAA patients of Shen-Yin deficiency type than those in the CAA patients of Shen-Yang deficiency type (P < 0.05 or P < 0.01).</p><p><b>CONCLUSION</b>(1) The abnormal high expression of peripheral blood co-stimulatory molecules CD28 suggested CD28 disorder may play an important role in immuno-pathogenesis of CAA. (2) The levels of peripheral CD28, CD8+ CD28+ expression and CD8+ CD28+/CD8+ CD28- can be taken as an objective indexes for TCM typing of CAA, which was disordered more severe in patients of Shen-Yin deficiency type than in those of Shen-Yang deficiency type.</p>