Environmental scanning electron microscopic study of macrophages associated with the tunica vasculosa lentis in the developing rat eye.

AIMS To demonstrate the value of environmental scanning electron microscopy (ESEM) when used in combination with immunogold/silver enhancement methods as a valuable tool in ocular research, and to determine the phenotype of macrophages associated with the tunica vasculosa lentis while maintaining a topographical view of the lens surface. METHODS Prenatal and postnatal rat eyes were investigated by conventional scanning electron microscopy and ESEM. In the latter case tissues were prestained with a panel of antileucocyte monoclonal antibodies and visualised with colloidal gold conjugated secondary antibody followed by silver enhancement. RESULTS The preliminary data demonstrate that ED1(+) ED2(+) macrophages occur in large numbers around the lens and are associated with sectors of both normal vessels and those undergoing regression. CONCLUSION The present study demonstrates that ESEM is an ideal way to combine scanning electron microscopy with immunohistochemistry and is therefore likely to have multiple other applications in ocular research.