DOCK8 deficiency impairs CD8 T cell survival and function in humans and mice
Randall KL., Chan SS-Y., Ma CS., Fung I., Mei Y., Yabas M., Tan A., Arkwright PD., Al Suwairi W., Lugo Reyes SO., Yamazaki-Nakashimada MA., de la Luz Garcia-Cruz M., Smart JM., Picard C., Okada S., Jouanguy E., Casanova J-L., Lambe T., Cornall RJ., Russell S., Oliaro J., Tangye SG., Bertram EM., Goodnow CC.
In humans, DOCK8 immunodeficiency syndrome is characterized by severe cutaneous viral infections. Thus, CD8 T cell function may be compromised in the absence of DOCK8. In this study, by analyzing mutant mice and humans, we demonstrate a critical, intrinsic role for DOCK8 in peripheral CD8 T cell survival and function. DOCK8 mutation selectively diminished the abundance of circulating naive CD8 T cells in both species, and in DOCK8-deficient humans, most CD8 T cells displayed an exhausted CD45RA+CCR7− phenotype. Analyses in mice revealed the CD8 T cell abnormalities to be cell autonomous and primarily postthymic. DOCK8 mutant naive CD8 T cells had a shorter lifespan and, upon encounter with antigen on dendritic cells, exhibited poor LFA-1 synaptic polarization and a delay in the first cell division. Although DOCK8 mutant T cells underwent near-normal primary clonal expansion after primary infection with recombinant influenza virus in vivo, they showed greatly reduced memory cell persistence and recall. These findings highlight a key role for DOCK8 in the survival and function of human and mouse CD8 T cells.