system
Given the following post, respond as if you're commenting on Reddit:
human
When a antigen-presenting cell activates a Th-cell, does the Th-cell take the antigen? Or does the antigen-presenting cell keep it?

Just really really curious what people know about this detail. I've seen 1 video where the MHC II gives the antigen to the TCR, but I cannot find a verification anywhere on the internet. Thought I'd give it a shot in here, maybe there are some experts? :D

Title of the video: 'The Adaptive Immune System'
By 'Vaccine Makers Project'. It happens at 30 seconds.
gpt
No, the T cell receptor doesn't have a proper pocket to bind a peptide antigen. That pocket is in the MHC molecule, and the peptide antigen stays in there.

The binding affinity for just the peptide alone would be low, the T cell receptor really recognizes a particular combination of MHC and peptide.