Differential PsaA-, PspA-, PspC-, and PdB-Specific Immune Responses in a Mouse Model of Pneumococcal Carriage

Open Access
Publisher Website
Google Scholar
Abstract
Larger numbers of pneumococci were detected in the nasal tract compared to the lung, cervical lymph nodes, and spleen 1, 2, 4, 7, 14, and 21 days after nasal challenge withStreptococcus pneumoniaestrain EF3030. In this mouse model of pneumococcal carriage, peripheralS. pneumoniaepneumococcal surface adhesin A (PsaA)-specific humoral responses (immunoglobulin G2a [IgG2a] ≫ IgG1 = IgG2b > IgG3) were significantly higher than pneumococcal surface protein A (PspA)-specific, genetic toxoid derivative of pneumolysin (PdB)-specific, or pneumococcal surface protein C (PspC)-specific serum antibody levels. However, PspA-specific mucosal IgA antibody levels were significantly higher than those against PsaA, PdB, and PspC. In general, both PsaA- and PspA-specific lung-, cervical lymph node-, nasal tract-, and spleen-derived CD4+T-cell cytokine (interleukin-4, interleukin-6, granulocyte-macrophage colony-stimulating factor, gamma interferon, and tumor necrosis factor alpha) and proliferative responses were higher than those for either PspC or PdB. Taken together, these findings suggest that PsaA- and PspA-specific mucosal responses as well as systemic humoral and T helper cell cytokine responses are predominantly yet differentially induced during pneumococcal carriage.

This publication has 72 references indexed in Scilit: