University of Alabama at Birmingham, Department of Pathology, Birmingham, AL 35294-2170, USA.
Infect Immun. 2011 Jan;79(1):314-20. doi: 10.1128/IAI.00768-10. Epub 2010 Nov 1.
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.
由于 23 价肺炎球菌多糖疫苗（PPV23）对老年人的效果不如对年轻人，因此重要的是要研究老年人中 PPV23 效果降低的免疫基础。我们通过测量血清 IgG、IgM 和针对血清型 14、18C 和 23F 的调理能力来确定年轻（n=55）和老年（n=44）成年人中 PPV23 的效果。虽然年轻和老年人对肺炎球菌多糖（PPS）的 IgG 抗体水平没有差异，但老年人针对所有三种血清型的 IgA 和 IgM 抗体水平均低于年轻人。在两个年龄组中，抗 PPS IgA 或 IgM 抗体水平均远低于抗 PPS IgG 抗体水平。年轻成年人对血清型 14 和 23F 的调理能力高于老年人。为了确定抗 PPS IgA 或 IgM 抗体对年轻和老年人之间功能差异的影响，我们通过亲和层析从免疫血清中去除抗 PPS IgA 或 IgM 抗体。当去除 IgM 抗体时，年轻和老年人之间的调理能力差异对于血清型 14 和 23F 消失（但对于血清型 18C 则没有）。然而，当去除 IgA 抗体时，两个年龄组之间没有显著差异。总之，尽管与抗 PPS IgM 抗体水平相比，抗 PPS IgG 抗体水平较高，但仅低水平的抗 PPS IgM 抗体就可以解释用 PPV23 免疫的年轻人和老年人之间观察到的一些肺炎球菌血清型的功能差异。
