Characterization Of Follicle-stimulating Hormone Receptor(FSHR) As A Molecular Target In Tumor Therapy

[Back ground]: Follicle- stimulating hormone receptor(FSHR), secreted by pituitary gland, is a gonadal hormone. FSHR belongs to G protein-coupled receptor family, a transmembrane glycoprotein which has the functions of promote ovulation and sperm formation. Recent study have shown that FSHR is over expressed in vascular endothelium of multiple types of human tumors, but isn’t expressed in normal tissues and inflammatory tissues. Thus, FSHR is a potential tumor marker,preparations of FSHR specific antibodies has diagnostic and therapeutic value in tumor therapy. Camelidae immune system have a unique heavy chain antibodies(HCAb) which naturally lack L chains. Compared to convention antibodies, heavy chain antibodies have smaller molecule, better stability and easy to prepare. The special structural and biochemical characteristics of its variable area endow them with more advantages, would be a candidate molecules of research and development of antibody-based drugs.[Research Objectives]:To obtain camel anti FSHR polyclonal antibodies, use it conduct anti tumor treatment in mice tumor, study its effects on growth of mouse tumor.[Research methods] :FSHR 234 recombinant protein was expressed in E.coil BL21 by IPTG induction. Used the recombinant protein to periodically immune the Xinjiang camel. Collect camel blood sample before and after immunization.Anti-FSHR antibody titer was detected by Enzyme-Linked Immunosorbant Assay(ELISA) by use the blood samples. When the antibody titer reaches the requirement,collect 300 ml of blood from camel jugular vein, isolate the anti-FSHR Polyclonal Antibody and testing its activity. Same time, CT-26 cells was cultured, use the cells to establish Balb/C mice transplanted tumor model, tumor-burdened mice were divided into blank group, negative control group and experimental group. Anti tumor treatment was conducted by tail intravenous injection of PBS, not immune serumand anti FSHR camel poly clonal antibodies respectively at the dose of 20 mg/kg,antibodies effect on tumor growth was observed and detected.[Results]: Obtained 0.227 mg/ml FSHR234 recombinant protein by prokaryotic expression of IPTG induced BL21-p ET-30a-fshr234,use the FSHR recombinant protein immune Xinjiang camel gets FSHR poly clonal Antibody which antibodies titer reaches to 1:130 000. Western Blot result shows that camel anti-FSHR polyclonal antibodies specific bind to the FSHR recombinant protein.Flow Cytometry result shows that anti FSHR polyclonal antibodies specific bind to human FSHR which expressed on PC 3cell membrane. Immunohistochemistry results show that FSHR positive expressed in CT-26 tumor tissue. Tumor bearing BALB/c mice anti-tumor antibodies treatment shows that mouse tumor`s growth significantly inhibited by anti FSHR poly clonal antibodies.[Conclusion]: Preliminary studies have shown that anti-FSHR antibodies have inhibit mice tumor grows, it may be the result of inhibition of tumor angiogenesis,the exact mechanisms of it need to be further studied.