“…To assay culture supernatants of hybridoma cells, aliquots of IF cells were air‐dried on cover glasses (4.5 mm × 24 mm), fixed with 4% paraformaldehyde for 10 min, permeabilized with 20 mM NaOH for 45 s (Iwatani et al , 2005), and washed twice with PBS. The cells were consecutively incubated with mAbs and Alexa Fluor 488 (AF488) goat anti‐mouse IgG (Molecular Probes Inc.) diluted 2000‐fold with PBS, for 3 h at 25 °C or overnight at 4 °C, washed with PBS, stained with 0.25 μg mL −1 4′,6‐diamidino‐2‐phenylindole dihydrochloride (DAPI), and observed under differential‐interference‐contrast (DIC) and fluorescence microscopes (BX60, Olympus, Tokyo, Japan; TSC SL, Leica).…”