Extracellular pH Regulates the Entry of Calcium into Jurkat T-cells

Abstract

The entry of calcium into blood cells is a key event in the launching of multiple transcription programs and in the development of immune response, proliferation, growth and cell differentiation. The TRPchannel superfamily serves as the main conductor of calcium ions in blood cells, most of the regulatory elements of which remain unknown. In the current work carried out on Jurkat cells using the patch-clamp method, we showed that the activity of TRPV5 and TRPV6 calcium channels (transient receptor potential vanilloid) of the TRP superfamily depends on the pH of the environment. Results of measurements of the intracellular Ca²⁺ level using a fluorescent Ca²⁺-specific Fluo-4 probe demonstrated that the entry of Ca²⁺ into Jurkat cells is also regulated by extracellular pH. The obtained data indicate that changes in the pH of the environment affecting the activity of the TRPV5 and TRPV6 calcium channels can regulate the entry and level of intracellular Ca²⁺ in Jurkat cells. It is suggested that such a mechanism for responding to changes in the acid–base balance is necessary for the cells of the immune system to trigger protective reactions, including the areas of development of various inflammations.