The role of LFA-1, Mac-1, ICAM-1 and Ia in the induction of Th-2 type of immune response in spleen during murine syngeneic pregnancy.

ABSTRACT

Murine syngeneic pregnancy is characterized by the transient splenomegaly at mid gestation. Recent studies from our laboratory have indicated the initiation of T-cell dependent B-cell response in the spleen during early pregnancy (Hegde and Nainan 1998). Present studies were carried out to understand the role of cell adhesion and MHC class II (Ia) molecules in the induction of Th-2 type of response in the spleen of pregnant mouse. Immunochemical localization of ICAM-1, LFA-1, Mac-1 and Ia in spleen have been carried out at different stages of pregnancy and formation of cell clusters and natural cell adhesion assay with splenocytes were carried out on day 1 (D1) pregnancy and compared with control. Upregulation of ICAM-1, LFA-1, Mac-1 and Ia was observed during early pregnancy. This coincided with the formation of germinal centers (GC) and Th2 type of interleukins in spleen as reported earlier. Increased expression of cell adhesion and Ia molecules during early pregnancy provides additional evidence for the systemic shift to Th2 type of immune response in syngeneic murine pregnancy.