Immunohistological staining of FFPE canine mast cell tumor tissue sections confirmed the ability of D12-κ, C11-κ, H1-κ, and C3-λ to target canine CD117 protein expressed in canine mast cell tumor tissue (Figure 7), demonstrating a similar staining pattern to the positive control YB5.B8. The gene discussed is KIT; the disease is mast cell neoplasm.