Role of infection in chronic obstructive pulmonary disease progression in an immunosuppressed rat pneumonia model.

, an opportunistic fungal pathogen, is the primary cause of pneumonia (PCP), which affects immunocompromised individuals and leads to high morbidity and mortality. colonization is associated with development of chronic obstructive pulmonary disease (COPD) in patients with HIV infection, and also non-sufferers, and in primate models of HIV infection. However, the mechanisms underlying infection in the pathogenesis of COPD have yet to be fully elucidated. To investigate the pathogenicity of infection and its role in COPD development, the present study established a PCP rat model induced by dexamethasone sodium phosphate injection. Expression of COPD-related biomarkers, including matrix metalloproteinases (MMPs) MMP-2, MMP-8, MMP-9, and MMP-12, and heat shock protein-27 (HSP-27), were quantified in the rat PCP model using reverse transcription-quantitative polymerase chain reaction, ELISA, western blot analysis, immunohistochemistry and gelatin zymography. Body weight, COPD symptoms, and pulmonary histopathology were assessed. Inflammatory cell counts in splenic tissues were measured using flow cytometry. It was identified that MMP and HSP-27 expression increased in the PCP rats, which was in agreement with previous literature. Therefore, it was hypothesized that infection may have an important role in COPD development.