Figure 3. The expression of CD15, CD68, CD3, CD20, CD57, and CD31 in the control HSK group. In the control HSK group, CD15- and CD68-positive cells were the main types of cells that infiltrated the stroma of the amniotic membrane (A and B). No CD3-, CD20-, CD57- or CD31-positive cells could be found in the amniotic membrane (C, D, E, and F). These cell markers could not be found in the amniotic membrane before transplantation (G). Scale bar: 20 μm.