Ki-67 staining is typically performed using immunohistochemistry (IHC). Here is a simplified overview of the procedure:
Fixation: Tissue samples are fixed using formalin to preserve cellular structures. Embedding: Fixed tissues are embedded in paraffin to facilitate thin sectioning. Sectioning: Thin sections of tissue (usually 4-5 µm thick) are cut and placed on microscope slides. Antigen Retrieval: Heat or enzymatic treatments are used to unmask antigens, making them accessible to antibodies. Blocking: Non-specific binding sites are blocked to prevent background staining. Primary Antibody Incubation: Slides are incubated with a primary antibody specific for Ki-67. Secondary Antibody Incubation: A secondary antibody conjugated to a detection system (such as HRP) is applied. Visualization: A chromogen (such as DAB) is used to produce a colorimetric reaction visible under a microscope. Counterstaining: Hematoxylin is often used to counterstain the nuclei, providing contrast.
