FIG. 1.

(A) BrdU labeling of DGBE cells. Confluent DGBE cells were labeled for 24 h with BrdU, and incorporation was detected using a mouse monoclonal anti-BrdU antibody and tetramethyl rhodamine isothiocyanate-conjugated anti-mouse immunoglobulins. Nuclei that have incorporated BrdU can be identified by their red fluorescence. A representative field is shown. Magnification, ×10. (B) Frozen cross sections of transwell membranes with transduced DGBE cells. Transwell membranes with DGBE cells transduced by pRtatpeGFP were fixed in 4% paraformaldehyde, embedded in Tissue-Tek O.C.T. compound (Sakura Finetek, Torrance, Calif.), frozen for 1 h at −80°C, and sectioned in a cryostat. A monolayer of cells covering the transwell membrane can be observed in a representative field with simultaneous fluorescent and bright-field illumination. Magnification, ×10.