Rapid identification and sorting of viable virus-reactive CD4(+) and CD8(+) T cells based on antigen-triggered CD137
Thomas C Wehler1, Michael Karg, Eva Distler
1Department of Medicine III - Hematology and Oncology, Johannes Gutenberg-University of Mainz, Mainz, Germany.
Insights
A new method uses CD137 (4-1BB) expression to identify and isolate antigen-specific CD4(+) and CD8(+) T cells. This approach detects more virus-reactive T cells than current methods, aiding immunotherapy research.
Area of Science:
- Immunology
- Cell Biology
- T-cell immunology
Background:
- Current methods for T-cell isolation rely on peptide/MHC multimers or cytokine production.
- These methods have limitations in detecting the full spectrum of antigen-specific T cells.
Purpose of the Study:
- To investigate the de novo cell surface expression of CD137 (4-1BB) as a marker for activated human CD4(+) and CD8(+) memory T cells.
- To establish a novel method for detecting and isolating antigen-specific T cells.
Main Methods:
- Analysis of CD137 expression on human CD4(+) and CD8(+) T cells after antigen stimulation.
- Co-staining with peptide/HLA tetramers to confirm specificity.
- Comparison of CD137-based enrichment with IFN-gamma secretion assay for isolating virus-reactive T cells.
- Magnetic-activated cell sorting (MACS) for purification and in vitro expansion of CD137(+) T cells.
Main Results:
- CD137 is expressed on recently activated, but not resting, human CD4(+) and CD8(+) memory T cells.
- Maximum CD137 expression occurs 24 hours post-antigen stimulation.
- CD137(+) T cells represent a broader repertoire of antigen-specific T cells, including those not producing IFN-gamma.
- CD137-based enrichment yielded 2-fold higher numbers of anti-viral T cells compared to the IFN-gamma assay.
Conclusions:
- Antigen-triggered CD137 expression provides a rapid method for detecting and sorting virus-reactive CD4(+) and CD8(+) T cells.
- The CD137 assay is valuable for monitoring anti-viral T helper and effector cells in immunotherapy and clinical trials.
Abstract:
Current methods for the detection and isolation of antigen-specific CD4(+) and CD8(+) T cells require the availability of peptide/MHC multimers or are restricted to cells that produce cytokines after antigen contact. Here we show that de novo cell surface expression of the TNF-receptor family member CD137 (4-1BB) identifies recently activated, but not resting, human CD4(+) and CD8(+) memory T cells. Maximum CD137 expression level is uniformly observed in both T-cell subsets at 24h after stimulation with antigen. In experiments with CMV and EBV-reactive T cells, we confirmed the specificity of CD137 expression by co-staining with peptide/HLA tetramers. Substantial proportions of CD137(+) T cells did not produce IFN-gamma, suggesting that CD137 detects a broader repertoire of antigen-specific T cells. Activated CD137(+) T cells could be easily purified by MACS and expanded in vitro thereafter. This CD137-based enrichment method was capable of isolating 2-fold higher numbers of anti-viral CD4(+) and CD8(+) T cells compared to the IFN-gamma secretion assay. In conclusion, antigen-triggered CD137 expression allows the rapid detection and sorting of virus-reactive CD4(+) and CD8(+) T cells. The CD137 assay is most attractive for the simultaneous targeting of anti-viral T helper and effector cells in monitoring studies and adoptive immunotherapy trials.
