3T3-L1 cells were induced to differentiate as described in the Methods. Cells were exposed to dose-responses (2-fold dilutions from maximal concentrations) of indoor house dust extracts and assessed for degree of triglyceride accumulation and pre-adipocyte proliferation ten days post-exposure. (A, D, G) Percent raw triglyceride accumulation per well relative to maximal intra-assay response for rosiglitazone for select dust extract dose-responses. (B, E, H) Increase (pre-adipocyte proliferation) or ecrease (potential cytotoxicity) in DNA content relative to vehicle control for select dust extract dose-responses. (C, F, I) Percent normalized triglyceride accumulation per cell relative to maximal intra-assay rosiglitazone response (normalized to DNA content) for select dust extract dose-responses. Data presented as mean ± SEM from three independent experiments (n=4 per experiment). Colors represent dust samples from unique households.