Increased Extracellular ATP in Plasma of Rheumatoid Arthritis Patients Activates CD8⁺T Cells

Rheumatoid arthritis (RA) is an autoimmune disorder with genetic and environmental causes often linked with the disease etiology. A disrupted metabolism has often been a characteristic of RA and an altered metabolic state of immune cells has been associated with their phenotypic and functional changes. The energy in the form of ATP produced by the metabolically active cells may thus initiate a cascade of immune responses there by influencing the disease pathogenesis or progression.

Through this study we have focused on determining the role of ATP in etiology of RA and aberrant cellular functions.

Blood samples of 80 healthy controls (HC) and 95 RA patients were screened for extracellular ATP concentration, transcriptome analyses, an inflammatory mediator and the results were statistically analysed.

In this study, ATP is shown to be excessive in the plasma of RA patients (453.5 ± 16.09% in RA vs. 233.9 ± 10.07% in HC, p <0.0001) and significantly increases with the disease severity. The abundant extracellular ATP could activate circulating cytotoxic CD8⁺T cells in RA patients to produce Granzyme B.

Plasma ATP is thus identified to have a significant potential in progression and prognosis of RA and may thus be studied further to design better therapeutic approaches for the disease.