CD8αα and CD8αβ T cells differential expression during late chronic experimental autoimmune encephalomyelitis

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Presentation Time: 11:30 AM - 12:45 PM
Poster Board Number: B771
Abstract ID: 7674

Presenting Author:
Ibtissam Essaghir , Graduate Student at Univ. of Utah Sch. of Med.

Abstract:

Multiple sclerosis is a chronic autoimmune demyelinating disorder affecting a total of 2.8 million people worldwide. The majority of the research in multiple sclerosis has focused on myelin-specific CD4 T cells since MHC class II molecules are the number one risk factor for developing the demyelinating disease. However, other cell types, like CD8 T cells, are involved in MS pathophysiology. Here, we investigate CD8 T cell subset contribution using an animal model of chronic progressive autoimmune disease known as Experimental Autoimmune Encephalomyelitis (EAE). The disease course was monitored until a late chronic time point, which we identified as later than 80 days post-induction. Our data shows that CD8 T cells differentiate based on CD8α and CD8β protein expression and correlate with disease severity. The percentage of CD8 T cell subsets; CD8αα, CD8αβ low, and CD8αβ high, varies between peak and late chronic disease stages as well as CNS and periphery. CD8αα T cells were highly expressed in the CNS. Our single-cell analysis of CD8αα, CD8αβ low, and CD8αβ high at a late chronic stage showed that these subsets have distinguished gene signatures. In addition, we measured the pMHC-TCR affinity at the single-cell level using a micropipette-based assay and found that the affinity correlates with disease severity. Thus, our results show that CD8 T cells contribute to demyelinating disease pathogenesis.