Application Of Polyphenol Coating Adhered To Serum Protein In Circulating Tumor Cell Capture

Cancer is one of the most serious diseases severely affecting human health and also is the second leading cause of death worldwide.Metastasis and recurrence of cancer are the major causes of death.Circulating tumor cells（CTCs）are a key part of the process of cancer metastasis.Circulating tumor cells are the surviving tumor cells that fall off from the primary tumor or metastases and enter the circulation of peripheral blood.Capture of CTCs from peripheral blood plays an important role in the diagnosis and treatment of patients and the formulation of personalized plans.Using polyphenol coating to capture tumor cells can achieve fast and broad-spectrum capture,and has a certain anti-adhesion effect on white blood cells,but the capture effect needs to be further improved due to the 76%low capture yields.Based on the differences between the integrins and their ligands of tumor cells and leukocytes,Here we proposed to a strategy that regulate the adhesion of biomaterial surface proteins to activate the surface integrins of tumor cells but not leukocytes.This new method of using integrin differential to capture CTCs is the most effective capture technique among the flat surface reported so far.This paper mainly carries out the following three aspects of work:（1）The polyphenol coating was prepared on the glass substrate via chelation of polyphenols with metal ions.the polyphenol coating which can interact with protein and maintain good protein activity.Thus,TA-Pro coating was further prepared by modifying serum protein adhesion on the surface of the polyphenol coating.Through the optimization ahhesionsof conditions,10%vol serum is determined to saturate to adsorb,simultaneously with the capture yield of tumor cells best,which was85%±2%.In addition,we used inert albumin adsorption as a control,and found that the efficiency of cell capture decreased,indicating the important role of serum protein.（2）The capture conditions to targeted tumor cells were further optimized,and it was found that when the serum protein concentration in the culture media was 20%,the cell capture efficiency was 92%±3%,higher than the 76%of non-protein adsorbed polyphenol coating.RNA-seq analysis showed that the gene expression of tumor cells captured on TA-Pro coating was significantly different from on the polyphenol coating,especially in the ECM-receptor interaction pathway ITGB1 and ITGAV.ITGB1 and ITGAV encode integrinα_Vβ₁,indicating that integrins play an indispensable role in cell capture.（3）Finally,the TA-Pro coating was applied to capture CTCs.For MCF-7cells,the capture time reached a peak at 90 min,and the TA-Pro coating could achieve broad spectrum capture to various tumor cells.We continued to culture the captured tumor cells and found that the TA-Pro coating had little effect on the growth of the cells,showing a excellent cell compatibility.Then the anti-adhesion effect of the material on white blood cells was investigated and the polyphenol-protein was applied to the blood samples of simulated patients.The capture efficiency of tumor cells was88%±6%.In summary,this paper for the first time realized the strategy of capturing CTCs by using the differences of different cell surface integrins and ligands,and the material preparation is simple and easy to obtain.It provides a new and promising platform for the capture and culture of circulating tumor cells,contributing to basic and clinical research.