ADGRG1 and COVID-19: Despite their resemblance to VM cells, some of the GPR56+ cells could have developed from naïve cells via conventional, non-bystander pathways – e.g., some could be developed during acute COVID-19 and are specific for SARS-CoV-2, although none of these cells had a CDR3 sequence that matches a public clone deemed to be specific for SARS-CoV-2 (data not shown).