Anti-cytokine therapy has revolutionized immunological disease treatment, but is not always effective and subject to treatment resistance as the cytokine cascade is highly redundant and multiple cytokines are involved in inflammation. Targeting a critical common regulator of inflammatory effectors is desirable. Lipopolysaccharide (LPS)-responsive beige-like anchor (LRBA) is a master regulator of multiple genes important for inflammation. Subcellular localization shows that LRBA translocated to the nucleus upon LPS stimulation and colocalized with multiple proteins associated with the endosome membrane system, indicating a critical role in membrane/vesicle trafficking essential for deposition, secretion and signal transduction of immune effectors. Deregulation, deficiency, down-regulation and overexpression of LRBA causes defective trafficking and signaling of immune effector molecules, resulting in immunodeficiency and autoimmunity diseases associated with a broader spectrum of severe symptoms when compared to other CVID genes. Modulating LRBA through antibodies, dominant negative mutants, or small interference RNA can be used to treat inflammatory diseases.