The human placenta is a hematopoietic organ during the embryonic and fetal periods of development

article i nfo We studied the potential role of the human placenta as a hematopoietic organ during embryonic and fetal development. Placental samples contained two cell populations—CD34 ++ CD45 low and CD34 + CD45 low —that were found in chorionic villi and in the chorioamniotic membrane. CD34