Tetramer-Based Enrichment of Preexisting Anti-AAV8 CD8+ T Cells in Human Donors Allows the Detection of a TEMRA Subpopulation.

ABSTRACT: Pre-existing immunity to AAV capsid may compromise the safety and efficiency of rAAV-mediated gene transfer in patients. Anti-capsid cytotoxic immune responses have proven to be a challenge to characterize because of the scarcity of circulating AAV-specific CD8+ T lymphocytes which can seldom be detected with conventional flow cytometry or ELISpot assays. Here, we used fluorescent MHC class I tetramers combined with magnetic enrichment to detect and phenotype AAV8-specific CD8+ T cells in human PBMCs without prior amplification. We showed that all healthy individuals tested carried a pool of AAV8-specific CD8+ T cells with a CD45RA+ CCR7- terminally-differentiated effector memory cell (TEMRA) fraction. Ex vivo frequencies of total AAV-specific CD8+ T cells were not predictive of IFNγ ELISp

SUBMITTER: Vandamme C 

PROVIDER: S-EPMC6990124 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature