Figure 2

Double immunohistochemical detection of Fuc-TVII and CLA in peripheral blood mononuclear cells (PBMC) (A) and purified CD4⁺ (B) and CD8⁺ (C) T cells (original magnification, × 132). PBMC were obtained from healthy blood donors. Purified CD4⁺ and CD8⁺ T cells were further isolated from the PBMC preparations by negative selection using a human CD4⁺ or CD8⁺ T cell subset column kit. A, Many CLA⁺ (blue) PBMC coexpress cytoplasmic Fuc-TVII (red) in a dot-like pattern. Two CLA⁺ Fuc-TVII⁺ PBMC appear to be blast-size T cells, because most of CLA⁺ PBMC with a monocyte/macrophage morphologic appearance show relatively intense and diffuse cytoplasmic staining for Fuc-TVII. Intense CLA surface staining is not necessarily associated with cytoplasmic Fuc-TVII staining (arrow). B, Dot-like expression of Fuc-TVII (red) is detected in the cytoplasm of some CD4⁺ T cells showing the intense membrane CLA staining (blue). Significant numbers of the CLA-expressing CD4⁺ T cells coexpressed Fuc-TVII in a Golgi staining pattern; however, the intensity of cytoplasmic Fuc-TVII staining was not necessarily proportional to that of CLA surface staining. C, Some CLA⁺ (blue) CD8⁺ T cells coexpress cytoplasmic Fuc-TVII (red) in a dot-like pattern. Discordant expression of CLA and Fuc-TVII is seen in the CD8⁺ T cell population (arrow). Compared with CD4⁺ T cells, fewer CLA⁺ CD8⁺ T cells coexpressed Fuc-TVII.