CLEC1B and pulmonary emphysema: Though this may be due to the well-described limitations of modeling CS-induced emphysema in mice (60), the finding that CLEC2 KO mice develop severe emphysema within 4 mo, a timepoint that would not be sufficient for this phenotype in wild-type mice, and that blocking TLO formation can partially rescue emphysema in this model suggests a distinct and possibly more pathogenic role for TLOs formed in the setting of lymphatic dysfunction than those formed after CS exposure alone.