Immunohistochemical Analysis of Knee Joint

Knee joint sections were immunostained with anti-HO-1 antibody (1:75, ab52947, Abcam, Austin, TX, USA) using Vectastain ABC-AP alkaline phosphatase (Vector Laboratories, Burlingame, CA, USA) as described previously [22 (link)]. For anti-microtubule-associated protein 1 light chain 3 (LC3) antibody (1:100, AP1801a, ABGENT, San Diego, CA, USA), anti-manganese superoxide dismutase (MnSOD) antibody (1:100, SPC-117, StressMarq, Victoria, BC, Canada), sections in Immunoactive pH 6.0 (Matsunami Glass, Osaka, Japan) were heated in a microwave oven and kept at 85 °C for 1.5 minutes. Slides were cooled for 20 minutes at room temperature after antigen unmasking. After washing with PBS, 3 % H₂O₂ treated for 10 minutes, sections were blocked with 10 % serum for 20 minutes at room temperature. Antibodies were applied and incubated overnight at 4 °C. After washing with PBS, sections were incubated with biotinylated secondary antibody for 30 minutes at room temperature and then incubated using the peroxidase based Elite ABC system (Vector Laboratories) for 30 minutes. Slides were washed, and sections were incubated with 3,3 -diaminobenzidine (DAB) substrate.