title: Characterization of protective mucosal and systemic immune responses elicited by pneumococcal surface protein PspA and PspC nasal vaccines against a respiratory pneumococcal challenge in mice.
abstract: Pneumococcal surface protein A (PspA) and PspC are virulence factors that are involved in the adhesion of Streptococcus pneumoniae to epithelial cells and/or evasion from the immune system. Here, the immune responses induced by mucosal vaccines composed of both antigens as recombinant proteins or delivered by Lactobacillus casei were evaluated. None of the PspC vaccines protected mice against an invasive challenge with pneumococcal strain ATCC 6303. On the other hand, protection was observed for immunization with vaccines composed of PspA from clade 5 (PspA5 or L. casei expressing PspA5) through the intranasal route. The protective response was distinguished by a Th1 profile with high levels of immunoglobulin G2a production, efficient complement deposition, release of proinflammatory cytokines, and infiltration of neutrophils. Intranasal immunization with PspA5 elicited the highest level of protection, characterized by increased levels of secretion of interleukin-17 and gamma interferon by lung and spleen cells, respectively, and low levels of tumor necrosis factor alpha in the respiratory tract.
authors.affiliation: Centro de Biotecnologia, Instituto Butantan, São Paulo, Brazil.
authors.forename: D M
authors.initials: DM
authors.lastname: Ferreira
authors.forename: M
authors.initials: M
authors.lastname: Darrieux
authors.forename: D A
authors.initials: DA
authors.lastname: Silva
authors.forename: L C C
authors.initials: LC
authors.lastname: Leite
authors.forename: J M C
authors.initials: JM
authors.lastname: Ferreira
authors.forename: P L
authors.initials: PL
authors.lastname: Ho
authors.forename: E N
authors.initials: EN
authors.lastname: Miyaji
authors.forename: M L S
authors.initials: ML
authors.lastname: Oliveira
mesh_terms: D000281:Administration, Intranasal; D000818:Animals; D000907:Antibodies, Bacterial / Q000276:immunology; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D002478:Cells, Cultured; D016207:Cytokines / Q000378:metabolism; D005260:Female; D005822:Genetic Vectors; D007780:Lacticaseibacillus casei / Q000235:genetics; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008168:Lung / Q000276:immunology; D051379:Mice; D008810:Mice, Inbred C57BL; D008969:Molecular Sequence Data; D009504:Neutrophils / Q000276:immunology; D022242:Pneumococcal Vaccines / Q000008:administration & dosage* / Q000276:immunology*; D011018:Pneumonia, Pneumococcal / Q000517:prevention & control*; D017422:Sequence Analysis, DNA; D013154:Spleen / Q000276:immunology; D013296:Streptococcus pneumoniae / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000235:genetics; D037521:Virulence Factors / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001426:Bacterial Proteins; D016207:Cytokines; D022242:Pneumococcal Vaccines; C110344:SpsA protein, Streptococcus pneumoniae; D014614:Vaccines, Synthetic; D037521:Virulence Factors; C051592:pneumococcal surface protein A