Older Adults Have a Low Capacity To Opsonize Pneumococci Due to Low IgM Antibody Response to Pneumococcal Vaccinations

Abstract

Since the 23-valent pneumococcal polysaccharide vaccine (PPV23) is less effective for older adults than for young adults, it is important to investigate the immunologic basis for the reduced efficacy of PPV23 among older adults. We determined the effectiveness of PPV23 among young (n ‫؍‬ 55) and older (n ‫؍‬ 44) adults by measuring the serum IgG, IgM, and IgA concentrations and opsonic capacities against serotypes 14, 18C, and 23F. While young and older adults showed no difference in levels of IgG antibodies against pneumococcal polysaccharide (PPS), older adults had lower IgA and IgM antibody levels than young adults for all three serotypes. In both age groups, anti-PPS IgA or IgM antibody levels were much lower than anti-PPS IgG antibody levels. Young adults showed higher opsonic capacities than older adults for serotypes 14 and 23F. In order to determine the effects of anti-PPS IgA or IgM antibodies on the functional difference between young and older adults, anti-PPS IgA or IgM antibodies were removed from immune sera by affinity chromatography. The difference in opsonic capacity between young and older adults disappeared for serotypes 14 and 23F (but not for serotype 18C) when IgM antibody was removed. However, there was no significant difference between the two age groups when IgA antibody was removed. In conclusion, even though anti-PPS IgG antibody levels are high compared with anti-PPS IgM antibody levels, the low levels of anti-PPS IgM antibody alone can explain the functional difference observed between young and older adults immunized with PPV23 with regard to some pneumococcal serotypes.

Streptococcus pneumoniae Serotype 1 Burden in the African Meningitis Belt: Exploration of Functionality in Specific Antibodies

“…Due to their pentameric structure, IgM polymers contain 10 antigen-binding sites and are therefore efficient at activating the complement cascade (39). Recent studies have suggested an important contribution of IgM antibodies to the opsonic activity observed after PCV vaccination (40)(41)(42). Their contribution persisted for Ն1 year after the last vaccine dose (40) and decreased with age due to a reduced CD27 ϩ B-cell repertoire among elderly people (41).…”

“…Recent studies have suggested an important contribution of IgM antibodies to the opsonic activity observed after PCV vaccination (40)(41)(42). Their contribution persisted for Ն1 year after the last vaccine dose (40) and decreased with age due to a reduced CD27 ϩ B-cell repertoire among elderly people (41). There is little information on the question of protective activity of naturally induced IgM.…”

Development of a Fourfold Multiplexed Opsonophagocytosis Assay for Pneumococcal Antibodies against Additional Serotypes and Discovery of Serological Subtypes in Streptococcus pneumoniae Serotype 20

“…While ELISA was successful in correlating protection against homologous serotypes in children, ELISA results may not correlate with cross-protection (8). Also, adults are susceptible to pneumococcal infections despite having generally high levels of pneumococcal antibodies (13,14,16,17), so ELISA results may not correlate with protection in adults. Further, with increasing serotypes included in the conjugate vaccines, these vaccines are also being evaluated for use in adults; for example, Prevnar 13 is now approved for use in adults Ͼ50 years of age (www.fda.gov/NewsEvents/Newsroom /PressAnnouncements/ucm285431.htm).…”

Vaccination in the prevention of infectious respiratory diseases in adults

“…It produces a short immune response with low permanence for the production of antibodies, mainly after 65 years of age 49 (B). In some specific populations, revaccination was attempted five years after the first dose, without satisfactory results, as the improvement in the level of antibodies is transitory, with possible hyporesponsiveness 50.51 (B).…”