Identification of Human Immune Cell Subtypes Most Vulnerable to IL-1ß-induced Inflammatory Signaling Using Mass Cytometry

Hema Kothari; Corey M. Williams; Chantel McSkimming; Mythili Vigneshwar; Eli R. Zunder; Coleen A. McNamara

The copyright holder for this preprint (which was not peer-reviewed) is the . https://doi.org/10.1101/2020.04.19.047274 doi: bioRxiv preprint represent mucosal-associated invariant T (MAIT) cells 47-51 . These CD4 -CD8 + CD161 high T cells express reduced levels of CD8 and share phenotypic features with the Th17 cells, including expression of the chemokine receptors (CCR6, CCR2 and CXCR6), cytokine receptors (IL-23R and IL-18R) and RORC transcription factor 47,48,51 . Moreover, the CD4 -CD8 + CD161 high cells belong to the conventional TCR-αβ EM (CD45RO + CCR7 -) T cells 47,48 that are not exhausted or terminally differentiated, and a subset of these cells express IL-17, IFN-γ, TNF-α and IL-22 47,52 . Notably, gating total CD8 T cells following the strategy used by Billerbeck et al. 47 , we were able to distinctly identify the CD161 high cells that expressed relatively lower levels of CD8 (Supplementary Fig. 7e) . Furthermore, the CD4 -CD8 + CD161 high cells in cluster 8 colocalized with the CD8 low CD161 high subset when overlaid on the total CD8 T cells (Supplementary Fig. 7f ). In the present study, we did not measure expression of CXCR6, IL-23R and IL-18R. However, the expression of markers including CCR2, CCR6, CD45RO and CD127 on the CD8 + CD161 high T cells in cluster 8 (Fig. 2c) and absence of CCR7 expression (Supplementary In addition to the CD4 -CD8 + CD161 high cells, the CD4 -CD8subset within cluster 8 also showed induced expression of p-NF-kB in response to IL-1β (Supplementary Fig. 7a-c) . These CD4 -CD8cells expressed comparable levels of CD161 and displayed a phenotype very similar to the CD4 -CD8 + CD161 high cells within cluster 8 (Supplementary Fig. 7a,d and i-m) Another novel finding of the present study is the identification of CCR6 as a marker to identify T cells most responsive to IL-1β stimulation. Our analysis demonstrated that the IL-1β responsive CCR6 + cells belong to the EM phenotype and a majority of these CCR6 + EM T cells co-express CCR2 and CD26. Notably, circulating human CD4 and CD8 T cells capable of producing IL-17 are enriched in the author/funder. All rights reserved. No reuse allowed without permission.