Although not significant, the higher prevalence of diarrhea at the peak of infection (20 vs 3%) in mice receiving the FcN434D-ARP1 as compared to mice receiving Fc-ARP1, suggest a slight effect of the N434D substitution and potential involvement of Fc receptor (FcRn and TRIM21)-mediated intracellular neutralization. Here, TRIM21 is linked to infection.