Effective methods for immobilization of non-adherent Pv11 cells while maintaining their desiccation tolerance

Abstract

Abstract Pv11 is the only animal cell line that can be preserved in the dry state at room temperature. Pv11 was derived from embryos of the sleeping chironomid Polypedilum vanderplanki, which displays an extreme form of desiccation tolerance known as anhydrobiosis. Pre-treatment with a high concentration of trehalose for 48 h allows Pv11 cells to enter anhydrobiosis. In the dry state, Pv11 cells preserve transgenic luciferase while retaining its activity; thus, these cells could be utilized as a vessel for dry-preserving valuable biological materials without loss of activity. However, Pv11 cells grow in suspension, which limits their applicability; for instance, they cannot be integrated into microfluidic devices or used in devices such as sensor chips. Therefore, in this paper, we sought to develop an effective immobilization system for Pv11 cells that, crucially, allows them to maintain their anhydrobiotic potential even when immobilized. First, we examined the effectiveness of various immobilization systems commonly used in standard cell cultures and found that Pv11 cells exhibited a very high adhesion rates with both biocompatible anchor for membrane (BAM) and Cell-Tak coatings. We also found that Pv11 cells immobilized well to uncoated glass if handled in serum-free medium. Next, we investigated whether immobilized Pv11 cells could retain their anhydrobiotic ability. While trehalose treatment of Pv11 cells prior to immobilization allowed them to retain a high level of both desiccation tolerance and proliferative potential after rehydration, trehalose treatment of Pv11 cells after immobilization resulted in a significant decrease in desiccation tolerance. Thus, it is important to induce anhydrobiosis before immobilization. In summary, we report the successful development of a protocol for the dry preservation of immobilized Pv11 cells.