THE IMMUNOLOCALIZATION OF BCL-2 AT THE MATERNAL-FETAL INTERFACE IN HEALTHY AND FAILING PREGNANCIES

Programmed cell death by apoptosis occurs in both fetal and maternal t issues during early pregnancy. To investigate a role for apoptosis at the maternal-fetal interface, we have immunolocalized the bcl-2 protei n in formalin-fixed decidual and placental tissue collected from women undergoing surgical termination of pregnancy (n = 22), from women und ergoing a sporadic miscarriage (n = 16) and from women with a history of recurrent pregnancy loss (more than three consecutive pregnancy los ses; n = 22) undergoing a further miscarriage. In all three groups, bc l-2(+) cells were found in aggregates and dispersed in the stroma, and immunoreactivity was observed in glandular epithelium. Double immunos taining revealed that a majority of stromal bcl-2(+) cells were CD56() large granular lymphocytes. A computerized image analysis revealed n o significant differences in percentage area of bcl-2 or CD56(+) immun ostaining. Significantly more biopsies from the surgical termination g roup (4/10) had >20% positive immunostaining for CD56 compared with 0% in the other two groups combined (0/20; P < 0.05). Bcl-2 immunoreacti vity was observed in the villi syncytiotrophoblast, and staining inten sity was consistently greater in the surgical termination group. The p ossible roles of bcl-2 at the maternal-fetal interface are discussed.