[Preparation and characterization of the monoclonal antibody against human sperm protein 17]

To prepare and characterize the monoclonal antibody (mAb) against sperm protein 17 (Sp17).

Human Sp17 cDNA was cloned and recombinant Sp17 protein was expressed as a fusion protein with an N-terminal 6-His tag. The purified recombinant Sp17 protein was used to immunize BALB/c mice for preparing mAb. mAb-produced hybridoma cells were screened by ELISA and the specificity of mAb was analyzed by immunohistochemical staining and blocking test.

Two hybridoma cells (3C12 and 3D6) secreting mAb against Sp17 were developed. The isotypes of these two mAbs, 3C12 and 3D6, were IgG(1) and IgM, respectively. ELISA detection showed that titers of mAbs, 3C12 and 3D6, were 1:64, 1:32 in cultured supernatant and 1:1 x 10(5), 1:5 x 10(4) in ascites, respectively. The results of immunohistochemical staining and blocking test indicated that 2 mAb specifically bound to Sp17 in human and rat testis and human ejaculated spermatozoa. Anti-Sp17 mAb also detected Sp17 in ovarian cancer.

The successful preparation of anti-Sp17 mAb will be useful for assessing the native distribution and aberrant expression of Sp17 protein.