The expression of HLA-A , B , C , DR antigen was dected mainly on dendritic and lymphoid cells. While along with the fetus growth, the number of positive cell was decreased, but the proportion of dendritic positive cell was increased gradually.

• HLA－A、B、C、DR抗原主要表达于淋巴样细胞与树突状细胞，胎龄愈大阳性细胞数愈少，但树突状细胞比例增大。