a, Flow cytometry of peritoneal macrophage subsets from Bhlhe40+/+, Bhlhe40-/-, and Bhlhe40-/- Il10-/- mice treated with PBS or IL-4c (representative of 2 experiments, n = 3 PBS-treated Bhlhe40+/+, 2 PBS-treated Bhlhe40-/-, 3 PBS-treated Bhlhe40-/- Il10-/-, 5 IL-4c-treated Bhlhe40+/+, 7 IL-4c-treated Bhlhe40-/-, 4 IL-4c-treated Bhlhe40-/- Il10-/-). b, Numbers of LPMs as in a. c, Immunoblotting of cyclins D1-3, cyclin-dependent kinase (CDK) 2, CDK4, CDK6, E2F2, and beta actin in lysates of LPMs from Bhlhe40+/+ and Bhlhe40-/- mice unstimulated or treated with IL-4c (representative of 2 experiments, n = 2/group). d, Frequency of BrdU+ Bhlhe40+/+ (CD45.1), Bhlhe40+/+ (CD45.2), or Bhlhe40-/- (CD45.2) LPMs from mixed bone marrow chimera mice (generated as in Fig. 2a–f) treated with PBS or IL-4c, with LPMs from each donor recovered from the same recipient connected by a line (pooled from 2 experiments, n = 2 PBS-treated [Bhlhe40+/+ (CD45.1) +Bhlhe40+/+ (CD45.2)] and [Bhlhe40+/+ (CD45.1) +Bhlhe40-/- (CD45.2)]; 4 IL-4c-treated [Bhlhe40+/+ (CD45.1) +Bhlhe40+/+ (CD45.2)]; 5 [Bhlhe40+/+ (CD45.1) +Bhlhe40-/- (CD45.2)])). Data in b,d are mean ± s.e.m; (b) each symbol or (d) paired symbols represent an individual mouse. ***P < 0.001, (b) unpaired or (d) paired two-sided Student’s t-test.