Analysis of MHC II (I-A/I-E) expression as a marker of APC
activation
Expression of MHC Class II is an important regulator of APC function,
being elevated upon activation and correlating with antigen presenting
capacity, indicating immune cell maturation [28]. Analysis of the
intensity of expression of the MHC class II marker I-A/I-E (referred to
as MHC II) on lung APC subsets after RSV-RFP infection revealed
significantly increased expression on cDC (Figure 4A), macrophages
(Figure 4B) and B cells (Figure 4C) at 21 dpi, with macrophages also
showing an earlier increase at 7 dpi (Figure 4B). Thus, the maturing
impact of RSV infection on cDC and other APC subsets appeared
long-lasting following resolution of clinical symptoms.