Distinct injury responsive regulatory T cells identified by multi-dimensional phenotyping
Guo et al. Front Immunol (2022)
Imbalances in regulatory T cells (Tregs) can predispose people to secondary infections or inflammation-mediated complications following severe injury. Researchers in the Lederer Lab at Brigham and Women’s Hospital and Harvard Medical School previously identified a distinct subtype of Tregs that are activated in response to injury, identified by high expression of the marker CD44 (CD44high Tregs). Here, the team used mass cytometry in combination with RNA sequencing and TCR repertoire analytical methods to characterize injury responsive Treg subsets in mice to understand how this balance is changed by injury.
RNA sequencing identified unique gene signatures of CD44high Tregs, including genes associated with cell migration and trafficking to sites of inflammation. TCR repertoire analysis also showed that injury increased the diversity of CD44high Tregs more than other Treg subsets. The group then used a 39-marker mass cytometry panel to validate these gene signatures at the protein level. In support of their findings, unsupervised analysis of the mass cytometry data identified two clusters corresponding to the CD44high and CD44low Treg subsets, with only the CD44high Treg cluster increasing in abundance 7 days after injury.
Using a multi-platform approach, the group was able to answer their research hypothesis in an unbiased manner. Further, by identifying and validating the differential expression of protein markers on CD44high Tregs using mass cytometry, the researchers may have identified targets for fine-tuning the balance of these populations to guide patients safely through recovery from injury.
Reference citation: Guo F, Hancock B, Griffith A, Lin H, Howard K, Keegan J, Zhang F, Chicoine A, Cahill L, Ng J and Lederer J. 2022. Distinct Injury Responsive Regulatory T Cells Identified by Multi-Dimensional Phenotyping. Front. Immunol. 13:833100. doi: 10.3389/fimmu.2022.833100