Genetic ablation of Rankl expression in Ccl19-Cre+ MRCs resulted in a significant loss of CD169+ subcapsular sinus macrophages, reduced retention of viral particles in the subcapsular sinus, and significantly reduced B cell activation following infection with an attenuated vaccinia virus (Camara et al., 2019; Fig. 2 a). This evidence concerns the gene CCL19 and infection.