Immunohistochemical localization of SOLD1 protein in BT cell lines. Immunoreactive protein was detected in BT-C and BT-K using an anti-bovine SOLD1 antibody (anti-bSOLD1) (A, A’, C, and C’). Normal rabbit serum (NRS) was used as a control (B, B’, D, and D’). Nuclear DNA was stained with Hoechst 33342 (A’–D’). Scale bars = 50 μm. Higher magnification images of BT-K cells (E and E’) were obtained using an oil immersion lens, scale bars = 10 μm.