Positive Controls for Antigen-Driven Activation of CD4+ and/or CD8+ T Cell Memory
Accurate monitoring of antigen-specific T cell immunity depends on functional assays that require both T cells and antigen-presenting cells to be fully functional. However, various factors — including blood collection, storage, shipment, and subsequent PBMC isolation, cryopreservation, and thawing — can introduce variability that may compromise assay integrity.

For this reason, no T cell functional test is complete without evaluating the functional fitness of the PBMC being used. This essential quality check can only be achieved through the use of positive controls that directly assess the performance of antigen-specific T cells.

Recommended reading:
Lehmann et al., CERI, CEF-X, and CPI: Largely Improved Positive Controls for Testing Antigen-Specific T Cell Function in PBMC Compared to CEF. Cells, 2021. 10, 248.