The usefulness of intracellular adenosine-5′-triphosphate measurement in CD4+ cells in renal transplant

ImmuKnow (R) is an in vitro diagnosis method that uses patient samples of whole blood polyclonally stimulated with phytohaemagglutinin. It also measures the adenosine triphosphate (ATP) production by CD4+ T cells. The test aims to offer an objective and overall measurement of each individual's cellular immune response. The trial was designed with the idea of individually monitoring the immunosuppression administered to the transplanted patient. At the same time, it aims to help in achieving balance as a way of avoiding immunosupression excess and the associated adverse effects (infections, cancer, etc) or an immunosupression defect and the subsequent risk of allograft rejection. The majority of studies that have evaluated clinical usefulness display great diversity in terms of patient recruitment, the immunosupressor treatment received, the clinical variables analysed and, above all, the time between performing ImmuKnow (R) and the evaluated clinical event. The most consistent data show that this trial on T CD4+ cell functioning is useful for predicting the risk of infection in renal transplant patients. However, its use as a rejection risk indicator is unclear. Lastly, given the great variability of immune response amongst individuals and that of existing publications, it can be deduced that the isolated lmmuKnow (R) value does not have diagnostic capacity and only regular individual monitoring could provide definitive assistance in clinical decision making and immunosurpressor treatment changes. Other aspects of ImmuKnow (R) application in the clinical routine, such as trial cycles, require randomised prospective studies for more comprehensive information.