Simultaneous Observation of the Antigen Localization in an Identical Semithin Section with Both Light and Transmission Electron Microscopes

Localization of T-cells in thymus tissue was detected in cryostat sections by the peroxidase anti-peroxidase (PAP) method. On the other hand, localization of MTV (mammary tumor virus) in mammary tumor tissues was demonstrated in paraffin sections by the enzyme-labeled antibody method. After immunohistochemical staining, the sections were dehydrated and embedded in Quetol 812. Semithin sections were prepared and identical sections were observed simultaneously with both light and transmission electron microscopes (LM and TEM). Positive reactions in the cryostat sections were observed on the surface of the T-cells. In paraffin sections, positive reactions were demonstrated on the sites facing the lumen and within the lumen of all acini in mammary tumor tissues. In semithin sections, identical reactionpositive sites of the same sections were clearly demonstrated with both LM and TEM. © Oxford University Press.