Role of Inflammatory Risk Factors in the Pathogenesis of Streptococcus pneumoniae

Abstract

Streptococcus pneumoniae (Spn) is a colonizer of the human nasopharynx (NP), causing a variety of infections in humans including otitis media, pneumonia, sepsis, and meningitis. The NP is an immune permissive site which allows for the persistence of commensal bacteria. Acute or chronic respiratory airway inflammation constitutes a significant risk factor for the manifestation of Spn infections. The inflammatory conditions caused by an upper respiratory viral infection or respiratory conditions such as allergic asthma and chronic obstructive pulmonary disorders (COPDs) are implicated in the dysregulation of airway inflammation and tissue damage, which compromise the respiratory barrier integrity. These immune events promote bacterial outgrowth leading to Spn dissemination and invasion into the bloodstream. Therefore, suppression of inflammation and restoration of respiratory barrier integrity could contain Spn infections manifesting in the backdrop of an inflammatory disease condition. The gained knowledge could be harnessed in the design of novel therapeutic interventions to circumvent Spn bacterial infections.

Epidemiological characteristics of nasopharyngeal Streptococcus pneumoniae strains among children with pneumonia in Chongqing, China

“…Children with repeated wheezing were more likely to have positive nasopharyngeal S . pneumoniae detection, which is in agreement with other references 14,15 . Nasopharyngeal S .…”

“…As noted, the clinical manifestations of culture-positive children were obviously more serious than those of the negative ones, especially in younger children. The positive group not only had a longer recovery time, but also displayed higher levels of inflammatory markers than the negative group, which was consistent with previous reports 15,18 . These results supported S .…”

Mechanistic Insight into the Development of TNBS-Mediated Intestinal Fibrosis and Evaluating the Inhibitory Effects of Rapamycin

“…During tissue injury with a chemical, mechanical and infection condition, an inflammatory response triggers the tissue repair process. However, a dysregulated and pathological inflammatory response leads to developing scarring or a fibrotic reaction, which could impair the tissue repair function 9,18,19 . Here, we show the procedure for the TNBS-induced fibrosis animal model, which significantly shares pathophysiology with human Crohn's disease.…”

Granulocyte-targeted therapies for airway diseases

“…The accumulation and over activation of these cells impair the gaseous exchange in the lungs and increase cell wall disruption [165]. Interestingly, the unregulated inflammatory responses in the lungs can result in bacteria overgrowth and dissemination [166,167]. The production of proteases and cytokines by neutrophils contributes to the lung epithelial barrier disruption that results in bacteremia [168].…”