system
Given the following post, respond as if you're commenting on Reddit:
human
What does the recent research into T cells and cross immunity of COVID mean?

I am seeing lots of information regarding this, if you have caught another similar corona virus in the past even if you don’t have antibodies you may have T cells or memory cells that may produce a milder case of covid, from my understanding. 

Would this also be true if you were to later contract a mutated strain of Covid? What are the implications of this, in regards to “immunity” - does this mean that it’s possible that once more people get covid that at some point it may become like the common cold?
gpt
We don't even know to what extent T-cells or antibodies from previous SARS-CoV-2 infection prevents future infection, much less cross-reactive antibodies or T-cells. Previous evidence suggests the damage caused by this sort of coronavirus is mitigated by T-cells, and there's evidence more T-cell production is associated with a less severe disease course in COVID-19 patients, but that's it. That relationship may simply be a correlation. It could be that the immune response to SARS-CoV-2 is protective and that the response derived from previous coronavirus infections is harmful. We will have to wait for better studies. Most likely this will require prospective recruitment and monitoring, which is difficult and costly, but some work like this is ongoing.