Follicle-stimulating hormone (FSH) is a gonadotropin, a glycoprotein polypeptide hormone. FSH is synthesized and secreted by the gonadotropic cells of the anterior pituitary gland, and regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH and luteinizing hormone (LH) work together in the reproductive system. 

In both males and females, primary hypogonadism results in an elevation of basal follicle-stimulating hormone (FSH) and luteinizing hormone (LH) levels. FSH and LH are generally elevated in: primary gonadal failure, complete testicular feminization syndromes and menopause. FSH and LH are both decreased in failure of the pituitary or hypothalamus.

Anti-Human FSH Monoclonal Antibodies

A new generation of anti-FSH monoclonal antibodies, which was recently produced by CUSAg, makes possible the development of highly sensitive and rapid sandwich immunoassays. The sensitivity and specificity of anti-FSH monoclonal antibodies have been repeatedly tested by chemiluminescence immunoassay (CLIA).Our in-house assays have a linear detection range from0.32-200 mIU/mL. All recommended MAb combinations were evaluated in medium-scale clinical trials with blood samples.

Calibration Curve

All MAbs were tested in pairs as capture and detection antibodies to select the best two-site MAb combinations for the development of a quantitative sandwich immunoassay. Calibration curve forthe best two-site combination is shown in Fig.1. Detection antibodies were labeled with horse reddish peroxidase (HRP) andcapture antibodies were coated onto 96-microwell plate. The best selected MAbpair for human FSHimmunoassaysis (capture-detection respectively):

CSB-DA443BmN①- CSB-DA443BmN②

 Fig.1Calibration curve forFSH sandwichchemiluminescence immunoassay (CLIA)

Precision

Atwo member buffered protein based panel was assayed, using a single lot of reagents, in replicates of ten at two separate times on the CUSAgCLIAplatform. As shown in table1, the system showed excellent precision with CV≤10%.

Recovery

Known concentrations ofFSH were added to five aliquots of human serum. The concentration ofFSHwas determined and the resulting percent recovery was calculated. The recovery percentage mean valueof theFSHimmunoassay usingCUSAg FSH MAb was 104.0%.

Clinical Comparison

72 clinical blood samples wereseparately tested on the CUSAg CLIA platform and compared to a diagnostic kit from Siemens. Data from this study were analyzed using the Passing-Bablok regression method and are summarized in the following table and scatter plot. Results reveal good agreement between CUSAgimmunoassay and comparison assay.

Fig.2Clinicalcomparison of CUSAg FSH assay andcommercial diagnosticassay

FSH protein

A certain amount of excellent FSH protein (Catalog Number：CSB-DP443I)is also offered, it could be used ascalibrator in immunoassay.

References

1.Pierce, J G; Parsons, T F (June 1981). "Glycoprotein Hormones: Structure and Function". Annual Review of Biochemistry. 50 (1): 465–495

2.Jiang X, Liu H, Chen X, Chen PH, Fischer D, Sriraman V, Yu HN, Arkinstall S, He X (July 2012). "Structure of follicle-stimulating hormone in complex with the entire ectodomain of its receptor". Proc Natl Acad Sci U S A. 109 (31): 12491–6.

3.Häggström, Mikael (2014). "Reference ranges for estradiol, progesterone, luteinizing hormone and follicle-stimulating hormone during the menstrual cycle". WikiJournal of Medicine. 1 (1)