GeneAb™ CD99

Cluster of Differentiation 99 (CD99) is a glycosylated transmembrane protein expressed by lymphocytes, cortical thymocytes, granulosa cells of the ovary, pancreatic islet cells, Sertoli cells, and endothelial cells. CD99 produces diffuse membrane staining patterns on nearly all Ewing’s sarcoma and primitive peripheral neuroectodermal tumours. CD99 may be found in synovial sarcoma, neuroendocrine carcinoma, acute myeloid leukemia, mesenchymal chondrosarcoma, lymphoblastic lymphoma, small round blue cell tumours, solitary fibrous tumours, vascular tumours, and myeloid sarcoma. It produces heterogeneous staining patterns which must be accompanied by other antibody staining for a final diagnosis.