Anti-CD8 Antibodies Can Trigger CD8⁺ T Cell Effector Function in the Absence of TCR Engagement and Improve Peptide-MHCI Tetramer Staining

Clement, Mathew, Ladell, Kristin, Ekeruche-Makinde, Julia, Miles, John J., Edwards, Emily S.J., Dolton, Garry, Williams, Tamsin, Schauenburg, Andrea J.A., Cole, David K., Lauder, Sarah N., Gallimore, Awen M., Godkin, Andrew J., Burrows, Scott R., Price, David A., Sewell, Andrew K., and Wooldridge, Linda (2011) Anti-CD8 Antibodies Can Trigger CD8⁺ T Cell Effector Function in the Absence of TCR Engagement and Improve Peptide-MHCI Tetramer Staining. Journal of Immunology, 187 (2). pp. 654-663.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.4049/jimmunol.10039...
 
14
2


Abstract

CD8⁺ T cells recognize immunogenic peptides presented at the cell surface bound to MHCI molecules. Ag recognition involves the binding of both TCR and CD8 coreceptor to the same peptide–MHCI (pMHCI) ligand. Specificity is determined by the TCR, whereas CD8 mediates effects on Ag sensitivity. Anti-CD8 Abs have been used extensively to examine the role of CD8 in CD8⁺ T cell activation. However, as previous studies have yielded conflicting results, it is unclear from the literature whether anti-CD8 Abs per se are capable of inducing effector function. In this article, we report on the ability of seven monoclonal anti-human CD8 Abs to activate six human CD8⁺ T cell clones with a total of five different specificities. Six of seven anti-human CD8 Abs tested did not activate CD8⁺ T cells. In contrast, one anti-human CD8 Ab, OKT8, induced effector function in all CD8⁺ T cells examined. Moreover, OKT8 was found to enhance TCR/pMHCI on-rates and, as a consequence, could be used to improve pMHCI tetramer staining and the visualization of Ag-specific CD8⁺ T cells. The anti-mouse CD8 Abs, CT-CD8a and CT-CD8b, also activated CD8⁺ T cells despite opposing effects on pMHCI tetramer staining. The observed heterogeneity in the ability of anti-CD8 Abs to trigger T cell effector function provides an explanation for the apparent incongruity observed in previous studies and should be taken into consideration when interpreting results generated with these reagents. Furthermore, the ability of Ab-mediated CD8 engagement to deliver an activation signal underscores the importance of CD8 in CD8⁺ T cell signaling.

Item ID: 45200
Item Type: Article (Refereed Research - C1)
Keywords: anti-CD8 antibody; CD8+ T-cell activation; CD8⁺; pMHCI tetramer; T-cells; surface plasmon resonance
ISSN: 1550-6606
Funders: Wellcome Trust (WT), Cardiff University (CU), Medical Research Council (MRC), Leverhulme Trust (LT), Wales Office of Research and Development (WORD), National Health and Medical Research Council (NHMRC)
Date Deposited: 23 Aug 2016 02:19
FoR Codes: 11 MEDICAL AND HEALTH SCIENCES > 1107 Immunology > 110702 Applied Immunology (incl Antibody Engineering, Xenotransplantation and T-cell Therapies) @ 100%
SEO Codes: 92 HEALTH > 9201 Clinical Health (Organs, Diseases and Abnormal Conditions) > 920108 Immune System and Allergy @ 100%
Downloads: Total: 2
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page