Depletion of human CD141-positive DCs reduces IFN-α levels after polyICLC stimulation in huNSG mice. (A) CD141⁺ cDC depletion efficiency in huNSG mice. HuNSG mice were injected with PBS or 10 μg of αClec9A antibody intraperitoneally on 3 consecutive days. At 10 hours after the last injection, mice were injected with polyICLC and euthanized 11 hours later. Splenocytes were stained for flow cytometry, and the percentage of CD141⁺ cDCs within the CD11c-positive gate was determined. (B) CD1c⁺ cDC maturation in huNSG mice without and with CD141⁺ cDC depletion. Same as in panel A with flow cytometry staining for CD86 on CD1c⁺ cDCs. (C) Serum levels of IFN-α in huNSG mice without and with CD141⁺ cDC depletion. After injections, as in panel A, serum cytokine levels were determined for human pan-specific IFN-α by ELISA. Left, a representative experiment; right, plot: composite data from 3 experiments. Each data point represents one individually analyzed mouse. Statistical analysis was performed with the Mann-Whitney U test.