Infection of BMDM (Fig. 3A) from wild type (Cybb+/+) or NOX deficient mice (Cybb−/−) or mDC (Fig. 3B) from healthy donors or CGD patients who lack a functional NADPH oxidase system, resulted in equivalent or even elevated (in the case of human mDC) PKR phosphorylation compared to healthy controls, indicating that NADPH oxidase is not required for chlamydia induced PKR activation and differs from cholesterol. The gene discussed is EIF2AK2; the disease is chronic granulomatous disease.