LCN2 and infection: The importance of the SIgA format for the in vivo efficacy was further confirmed by the lower ability of CAA1 and CCG4 IgG to limit inflammation in comparison to their polymeric counterparts, as shown by PMN cells infiltration in the cecum and lipocalin-2 levels in the stools of the infected animals at 72 h post-infection (Figures 5B,C and Supplemental Figures 7B,C).