While granulomas were observed in both tMWCNT and rMWCNT-treated mice after 21 days, granuloma size was significantly greater in rMWCNT-treated mice compared to tMWCNT-treated mice, although there were no significant differences between Stat1+/+ and Stat1−/− mice (Fig. 3c). The gene discussed is STAT1; the disease is Granuloma.