Leukocyte trafficking through lung lymphatics requires Gαi signaling and Ccr7 expression. (A and B) Leukocyte flow through pulmonary lymphatics from Rosa26^mTmG mice treated with either vehicle control or pertussis toxin before challenge with LPS with the quantification of the effect of pertussis toxin in B. (C) Immunofluorescence images of lung sections from Ccr7^+/+ wild-type mice and Ccr7^−/− knockouts showing accumulation of MHC-II+ cells in bronchovascular cuffs. (D and E) Pulmonary lymphatic leukocyte flow in LPS-treated Ccr7^+/+:Rosa26^mTmG mice and the absence of intralymphatic leukocytes in Ccr7^−/−:Rosa26^mTmG mice, with (E) the quantification of the effect of Ccr7 knockout. White arrowheads in A and D point to intralymphatic leukocytes (also circled in white). Graphs show means ± SEM. P values are from unpaired, two-tailed t tests on log₁₀-transformed datasets. Group sizes: (B) n = 5; (C and E) n = 4.