Immunizations with Pneumococcal Surface Protein A and Pneumolysin Are Protective against Pneumonia in a Murine Model of Pulmonary Infection withStreptococcus pneumoniae

Abstract

Intranasal infection of mice with certain strains of capsular group 19 Streptococcus pneumoniae can result in focal pneumonia in the absence of bacteremia. Using this model of murine pneumonia, we demonstrated that immunization with recombinant forms of either pneumococcal surface protein A (PspA) or PdB (a genetically detoxified derivative of pneumolysin) elicited significant protection against focal pulmonary infection. This may be the first demonstration that a proposed vaccine antigen can protect against pneumococcal pneumonia. The best protection was obtained by immunizing mice with a mixture of PspA and PdB, indicating that the protection elicited by these antigens can complement each other. This result is in agreement with previous studies that used pneumococcal sepsis and nasal colonization models and demonstrate that the best protein vaccines for prevention of infection may be those that include more than one protection-eliciting pneumococcal protein.

Functions and Regulation of NF-κB RelA during Pneumococcal Pneumonia

“…SP3 is a virulent serotype of S. pneumoniae that readily proliferates in the lungs of WT, immunocompetent mice, resulting in ϳ100% mortality (12,34). Due to the uncontrollable growth of SP3 in the lungs, we used a less virulent and more effectively eliminated serotype of pneumococcus, SP19 (12,34), to determine requirements for RelA in bacterial killing during pneumonia.…”

“…Due to the uncontrollable growth of SP3 in the lungs, we used a less virulent and more effectively eliminated serotype of pneumococcus, SP19 (12,34), to determine requirements for RelA in bacterial killing during pneumonia. Lungs harvested from RelA-deficient mice had ϳ100-fold more viable bacteria than littermate controls expressing one or both copies of RelA (Fig.…”

Immunization with Polyamine Transport Protein PotD Protects Mice against Systemic Infection with Streptococcus pneumoniae

“…Proteins are, generally, antigenically conserved across all serotypes and stimulate a T-cell-dependent immune response resulting in more robust immunological memory (28). Several pneumococcal surface proteins have been shown to be effective immunogens and can prevent sepsis, pneumonia, and carriage in animal models (1,2,5,6,23,26).…”

Desenvolvimento e avaliação da resposta imune humoral de uma vacina anti-pneumocócica conjugada: polissacarídeo capsular sorotipo 14 - proteína de superfície pneumocócica A.

“…Desta forma, a proteção contra a colonização nasofaríngea é considerada essencial para indução da imunidade indireta na população, assim como é esperado que a redução na colonização exerça um efeito direto na redução da doença invasiva (BRILES et al, 2003;FUKUYAMA et al, 2010 BRILES et al, 2003;MIYAJI et al, 2002).…”

“…A imunização parenteral com PspA é capaz de proteger modelos murinos contra pneumonia pneumocócica e sepse (BRILES et al, 2003).…”