Application of Silicone Coating for Obtaining Cell Spheroids Using the Hanging Drop Method

Abstract

In modern experimental oncology, 3D cell cultures have become particularly important, as they provide more relevant results compared to traditional 2D cultures. The problem of obtaining relevant cell models remains urgent for the study of breast cancer. One of the most common techniques for obtaining a 3D culture is the hanging drop method. Researchers are constantly developing its modifications to reduce variations in the shape and size of the resulting cell spheroids. One of the ways to solve this problem is to apply a hydrophobic coating to the surface of cell culture plastics. Silicones or Parafilm® laboratory films are often used for this purpose. As a result, the curvature of the drop surface increases, which leads to accelerated aggregation of cells in the centre of the drop. The purpose of this research was to evaluate the possibility of applying a coating made of the silicone elastomer SIEL 159-330 (Russia) to modify the hanging drop method. Materials and methods. We used the SIEL 159-330 coating cured at a temperature lower than that recommended by the manufacturer and investigated its cytotoxic properties as well as its effect on the formation of cell spheroids in a hanging drop. The material for the study was the BT-474 breast cancer cell line. Results. The research found that the tested elastomer has no effect on cell viability. At the same time, SIEL 159-330, compared to polystyrene, significantly reduces the time of cell aggregate formation in the lower part of the drop. In addition, cell spheroids of the breast cancer culture obtained on the SIEL 159-330 coating vary less in shape and size than spheroids obtained on the polystyrene or Parafilm coating.