Biology of isolated immunocytes. II. Simultaneous detection of cell surface Ig and theta-antigen by immunoperoxidase staining at the ultrastructural level.

Surface Ig and theta-antigen of lymphocytes collected on the bottom of Beem capsules were stained by an indirect immunoperoxidase technique to compare B and T cells at the ultrastructural level. To distinguish the two markers, the surface Ig was allowed to cap during the incubation with anti-Ig antiserum while the incubation with anti-theta alloantiserum was performed at 4 degrees to obtain a staining in a ring pattern. This method was applied to the study of lymphocytes from spleen, lymph nodes and thymus of normal mice. Lymphocytes forming rosettes with SRBC were also studied at different days after immunization with SRBC.