a, Flow cytometry of Bhlhe40GFP transgene reporter expression in LPMs, SPMs, red pulp macrophages, Kupffer cells, kidney macrophages, and AMs from Bhlhe40GFP+ and Bhlhe40GFP- mice after PBS or IL-4c treatment (representative of 1–2 experiments, n = 3 PBS-treated Bhlhe40GFP+, 1 PBS-treated Bhlhe40GFP-, 5 IL-4c-treated Bhlhe40GFP+, 3 IL-4c-treated Bhlhe40GFP-). b, Numbers of LPMs, red pulp macrophages, Kupffer cells, and AMs from Bhlhe40+/+ and Bhlhe40-/- mice treated with PBS or IL-4c (pooled from 2 experiments, n = 4 PBS-treated Bhlhe40+/+, 3 PBS-treated Bhlhe40-/-, 8 IL-4c-treated Bhlhe40+/+, 7 IL-4c-treated Bhlhe40-/-). c-e, Flow cytometry of BrdU incorporation by red pulp macrophages (c), Kupffer cells (d), and AMs (e) from Bhlhe40+/+ and Bhlhe40-/- mice treated with PBS or IL-4c as in Fig. 5g. Data in b are mean ± s.e.m; each symbol represents an individual mouse (b). *P ≤ 0.05, unpaired two-sided Student’s t-test.