Evaluation of binding of FITC-prolactin conjugate to prolactin receptor

¯Abstract Background: Prolactin is an important mammalian hormone and the associated receptor is recognized in many different cells. Radioligand and histochemical methods are both used for assaying prolactin receptor. Objective: To produce FITC-prolactin conjugate and also to study the ability of conjugate to bind prolactin receptor. Methods: In this experimental study FITC was bound to prolactin in alkaline solution. FITC-prolactin conjugate was separated from free FITC by chromatographic method. Later, the ability of FITC-prolactin conjugate to bind prolactin receptor of peripheral blood mononuclear cells (PBMC) was assessed by flowcytometry. Findings: Fluorescence emission was detected in 2.1% of the cells in absence of FITC-prolactin. Following the addition of FITC-prolactin conjugate to cells for one hour and further washing, the fluorescence emission was detected in 27.8% of cells. For PBMC, these data were 0.02% and 11.8%, respectively. Conclusion: Regarding the data obtained in our study, FITC-prolactin conjugate can bind prolactin receptor. Therefore, this conjugate could be used for assessing prolactin receptor by fluorometric method.