CD99

CD99 antigen (Cluster of differentiation 99), also known as MIC2 or single-chain type-1 glycoprotein, is a heavily O-glycosylated transmembrane protein that is encoded by the CD99 gene in humans.

The protein has a mass of 32 kD. Unusually for a gene present on the X chromosome, the CD99 gene does not undergo X inactivation, and it was the first such pseudoautosomal gene to be discovered in humans.

An immunohistochemical study yielded positive results for CD34, CD99, and Bcl-2 and negative results for EMA, GFAP, and S100 in two Cases of Primary Intracranial Solitary Fibrous Tumor 1).

1)
Kikuchi A, Fujita T, Takahashi Y, Yokosako S, Yoshimura C, Akagawa H, Fujibayashi M, Kubo O, Onda H, Kasuya H. [Two Cases of Primary Intracranial Solitary Fibrous Tumor:Genetic Examination of <i>NAB2-STAT6</i> Fusion and Its Association with Hemangiopericytoma]. No Shinkei Geka. 2015 Jul;43(7):641-8. doi: 10.11477/mf.1436203090. Japanese. PubMed PMID: 26136329.