Effect of Pneumococcal Conjugate Vaccine on the Natural Antibodies and Antibody Responses Against Protein Antigens from Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis in Children with Community-Acquired Pneumonia.
Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis are common causative agents of respiratory infections. Pneumococcal conjugate vaccines (PCV) have been introduced recently, but their effect on the natural immunity against protein antigens from these pathogens has not been elucidated.
This was an age-matched observational controlled study that evaluated the influence of 10-valent PCV (PCV10) on the levels of antibodies and frequencies of antibody responses against proteins from S. pneumoniae, H. influenzae and M. catarrhalis in serum samples of children with community-acquired-pneumonia(CAP). Eight pneumococcal proteins (Ply, CbpA, PspA1 and 2, PcpA, PhtD, StkP and PcsB), three proteins from H. influenzae (including Protein D) and five M. catarrhalis proteins were investigated.
The study group comprised 38 vaccinated children and 114 age-matched controls (median age: 14.5 vs. 14.6 months, respectively; p=0.997), all with CAP. There was no difference on clinical baseline characteristics between vaccinated and unvaccinated children. Vaccinated children had significantly lower levels of antibodies against four of the studied pneumococcal antigens (p=0.048 for Ply; p=0.018 for PspA; p=0.001 for StkP; and p=0.028 for PcsB) and higher levels of antibodies against M. catarrhalis (p=0.015). Nevertheless, the vaccination status did not significantly affect the rates of antibody responses against S. pneumoniae, H. influenzae and M. catarrhalis.
In spite of the differences that have been found on the level of natural antibodies, no effect from pneumococcal vaccination was observed on the rate of immune responses associated with CAP against protein antigens from S. pneumoniae, H. influenzae and M.catarrhalis.
PMID: 26954601 [PubMed - as supplied by publisher]