Anti-protein immunoglobulin M responses to pneumococcus are not associated with aging.
German EL., Al-Hakim B., Mitsi E., Pennington SH., Gritzfeld JF., Hyder-Wright AD., Banyard A., Gordon SB., Collins AM., Ferreira DM.
BACKGROUND: The incidence of community-acquired pneumonia and lower respiratory tract infection rises considerably in later life. Immunoglobulin M (IgM) antibody levels to pneumococcal capsular polysaccharide are known to decrease with age; however, whether levels of IgM antibody to pneumococcal proteins are subject to the same decline has not yet been investigated. METHODS: This study measured serum levels and binding capacity of IgM antibody specific to the pneumococcal surface protein A (PspA) and an unencapsulated pneumococcal strain in serum isolated from hospital patients aged