Cell surface antigens: serial sectioning of single cells as an approach to topographical analysis.

The topographical distribution of H-2 antigens on the surfaces of C57BL/6 mouse thymocytes and lymph-node lymphocytes was investigated by a new technique. Single cells were reacted with visually labeled antibody directed against H-2 antigen. Each cell was processed for electron microscopy individually and was serially sectioned. Models constructed from serial electron micrographs provided detailed views of the entire cell surface and showed that H-2 antigen occurs on thymocytes in small isolated regions and on lymphocytes in large interconnected regions.