T-Cell Immune Surveillance in Allogenic Stem Cell Transplant Recipients: Are Whole Blood–Based Assays Ready to Challenge ELISPOT?

Abstract

We compared the feasibility of four CMV- and Aspergillus-reactive T-cell immunoassay protocols in allogenic stem cell transplant recipients. While ELISPOT performed best overall, logistically advantageous whole blood-based assays performed comparably in patients with less severe lymphocytopenia. CMV-induced interferon-gamma responses correlated strongly across all protocols and showed high concordance with serology.

Development of a Simple and Robust Whole Blood Assay with Dual Co-Stimulation to Quantify the Release of T-Cellular Signature Cytokines in Response to Aspergillus fumigatus Antigens

“…Additionally, the WB-ELISA protocol showed superior robustness to pre-analytic delays compared with previously published data for PBMC-based assays (including ELISA) to detect A. fumigatus-specific T-cell activation [12,13]. A recent study by our consortium further revealed an overall promising performance of WB-ELISA in allogenic hematological stem cell transplant recipients [57]. Specifically, high technical reliability and good concordance of IFN-γ response to CMV phosphoprotein 65 with CMV serostatus and reactivation was seen in patients with >800 lymphocytes per µL of peripheral blood.…”

“…Lastly, the patient cohort for validation of the assay in the present study was limited in size and did not cover patients with proven or probable invasive aspergillosis due to a lack of appropriate samples. Nonetheless, the technical reliability and high discriminatory power observed in the present study and the solid performance of our WB-ELISA system in allogenic stem cell transplant recipients [57] encourage future multi-center evaluation in immunocompromised patients.…”