In a house dust mite (HDM) induced allergic asthma mouse model, SPP1/Osteopontin was shown to significantly enhance the host’s ability to defend against Streptococcus pneumoniae infection by inhibiting airway inflammatory cell infiltration, alleviating tissue damage, and reducing proinflammatory cytokine levels, as manifested by a significant reduction in bacterial load in alveolar lavage fluid and lung tissue (66). This evidence concerns the gene SPP1 and allergic asthma.