CD8 Co-Receptor Enhances T-Cell Activation without Any Effect on Initial Attachment.
Philippe RobertLaurent LimozinP Anton van der MerwePierre BongrandPublished in: Cells (2021)
The scanning of surrounding tissues by T lymphocytes to detect cognate antigens requires high speed, sensitivity and specificity. T-cell receptor (TCR) co-receptors such as CD8 increase detection performance, but the exact mechanism remains incompletely understood. Here, we used a laminar flow chamber to measure at the single molecule level the kinetics of bond formation and rupture between TCR- transfected CD8+ and CD8- Jurkat cells and surfaces coated with five peptide-exposing major histocompatibility antigens (pMHCs) of varying activating power. We also used interference reflection microscopy to image the spreading of these cells dropped on pMHC-exposing surfaces. CD8 did not influence the TCR-pMHC interaction during the first few seconds following cell surface encounter, but it promoted the subsequent spreading responses, suggesting that CD8 was involved in early activation rather than binding. Further, the rate and extent of spreading, but not the lag between contact and spreading initiation, depended on the pMHC. Elucidating T-lymphocyte detection strategy may help unravel underlying signaling networks.
Keyphrases
- single molecule
- high speed
- induced apoptosis
- nk cells
- regulatory t cells
- high resolution
- gene expression
- dendritic cells
- deep learning
- machine learning
- escherichia coli
- label free
- high throughput
- oxidative stress
- immune response
- staphylococcus aureus
- mass spectrometry
- quantum dots
- peripheral blood
- transcription factor
- endoplasmic reticulum stress
- heat shock
- heat shock protein
- density functional theory
- structural basis
- aqueous solution