Protocadherin-15 in YT Human Cell Line. Protocadherin-15 was detected in immersion fixed YT human leukemia natural killer-like cell line using Mouse Anti-Human Protocadherin-15 Monoclonal Antibody (Catalog # MAB6729) at 10 µg/mL for 3 hours at room temperature. Cells were stained using the NorthernLights™ 557-conjugated Anti-Mouse IgG Secondary Antibody (red; Catalog # NL007 ) and counterstained with DAPI (blue). Specific staining was localized to cytoplasm. View our protocol for Fluorescent ICC Staining of Non-adherent Cells .