Neutrophils sorted from the dLNs after vaccination present Env to memory CD4⁺T cells but MDCs have the highest capacity. (A) Neutrophils and MDCs were isolated by flow cytometry sorting from the dLNs of vaccinated rhesus macaques 24 hours postinjection with an Alexa 680–labeled Env or PBS (contralateral arm) according to the depicted gating strategy. (B) Neutrophils isolated from the Env-draining LNs induced well-detectable T-cell proliferation but MDCs showed the highest capacity. Representative plots of proliferating CD4⁺ T cells. (C) Bars graph show percentages of proliferating CD4⁺ T cells (mean ± SEM, n = 3 NHPs). (D) Representative histograms show HLA-DR levels on neutrophils sorted from the Env and PBS dLNs. (E) Representative plots show proliferating CD4⁺ T cells after 5-day cocultures with either neutrophils, monocytes, or MDCs isolated from spleen from the animals above in presence of Env. (F) Bars show percentages of proliferating CD4⁺ T cells (mean ± SEM, n = 3 NHPs). (G-H) Rhesus macaques were injected with Alexa 680–labeled Env and the cell subsets recruited to the muscle injection site and dLNs were phenotyped and enumerated by flow cytometry. (G) Number of indicated cell subsets mobilized to the Env-injected muscle and dLNs (mean ± SEM, n = 3 NHPs); **P < .01. (H) Proportions of the number of Env⁺ cell subsets at the injection site and draining LNs. Mono, monocytes; Neutr, neutrophils.