CXCR3 and COVID-19: Evidence of the role of CXCR3+ TFH cells emerged in a prior COVID-19 study in which a positive correlation was identified between the presence of CXCR3+ circulating TFH1 cells (defined as CD4+CD45RA-CXCR5+CXCR3+CCR6-) and the circulating titre of SARS-CoV-2-specific antibodies (IgG specific for viral nucleocapsid and spike proteins; n = 13 adults) (34).