There must be some mechanism to adapt a measurement to t-cells, no? How can we be sure they do anything if we don't understand their quantitative impacts. I'm

There must be some mechanism to adapt a measurement to t-cells, no? How can we be sure they do anything if we don't understand their quantitative impacts. I'm aware of apparent Covid T-Cell detection kits which would tell you if you have any but you are right they are not correlated with patient outcome. I'm not aware that nABs serology is correlated with patient outcome either so why not include the existence above some threshold after some coarse verification? Incidental observation should be able to find a reasonable threshold?