MPO and systemic lupus erythematosus: To study the therapeutic efficiency of Ber-encapsulated SLE-chitosan nanoparticles and pure berberine, the histopathological changes of the lung tissues, levels of inflammatory cells and cytokines, and activities of myeloperoxidase (MPO) and superoxide dismutase (SOD) enzymes were evaluated in bronchoalveolar lavage fluid (BALF).