Figure 2.

Localization of laminin α3, α4 and α5 chains in comparison to thymic epithelial and endothelial cells. (a–c) Double immunofluorescence staining of bone marrow cryostat sections with the anti-laminin α3 chain antibody BM165 (a) and the antibody TE4 (b) specific for medullary thymic epithelial cells showed colocalization (c) of both antigens in the medulla (M). In the cortical region (C) almost no staining of both antigens could be observed. (d–f) The double labelling of bone marrow sections with the antiserum 377 against the laminin α4 chain (d) and the monoclonal antibody against PECAM (e) revealed a colocalization (f) of both antigens in thymic endothelial cells. (g–i) Thymic cortical epithelial cells, which are specifically labelled by the antibody TE3 (h), did not express the laminin α5 chain which is restricted to the subcapsular (SC) epithelial cells (g) or blood vessels. The overlay picture (i) showed only partial overlapping areas of both antigens in the subcapsular epithelium. (Original magnification ×55.)