AUTHOR=Landrith Tyler A. , Sureshchandra Suhas , Rivera Andrea , Jang Jessica C. , Rais Maham , Nair Meera G. , Messaoudi Ilhem , Wilson Emma H. 

TITLE=CD103+ CD8 T Cells in the Toxoplasma-Infected Brain Exhibit a Tissue-Resident Memory Transcriptional Profile

JOURNAL=Frontiers in Immunology

VOLUME=8

YEAR=2017

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2017.00335

DOI=10.3389/fimmu.2017.00335

ISSN=1664-3224

ABSTRACT=<p>During chronic infection, memory T cells acquire a unique phenotype and become dependent on different survival signals than those needed for memory T cells generated during an acute infection. The distinction between the role of effector and memory T cells in an environment of persistent antigen remains unclear. Here, in the context of chronic <italic>Toxoplasma gondii</italic> infection, we demonstrate that a population of CD8 T cells exhibiting a tissue-resident memory (T<sub>RM</sub>) phenotype accumulates within the brain. We show that this population is distributed throughout the brain in both parenchymal and extraparenchymal spaces. Furthermore, this population is transcriptionally distinct and exhibits a transcriptional signature consistent with the T<sub>RM</sub> observed in acute viral infections. Finally, we establish that the CD103<sup>+</sup> T<sub>RM</sub> population has an intrinsic capacity to produce both IFN-γ and TNF-α, cytokines critical for parasite control within the central nervous system (CNS). The contribution of this population to pro-inflammatory cytokine production suggests an important role for T<sub>RM</sub> in protective and ongoing immune responses in the infected CNS.</p><p><bold>Accession number:</bold> <bold>GSE95105</bold></p>