Department of Pediatrics, School of Medicine, Ewha Womans University, Seoul, Republic of Korea.
BMC Infect Dis. 2010 Mar 10;10:60. doi: 10.1186/1471-2334-10-60.
Streptococcus pneumoniae is a leading cause of morbidity and mortality in the elderly. To prevent invasive pneumococcal diseases, the 23-valent pneumococcal polysaccharide vaccine (PPV) is recommended in subjects over 65 years of age. Although it has been reported to provide approximately 50-80% protection against invasive disease in the general elderly population, there is still controversy as to the effectiveness of the PPV in the elderly.
To evaluate the immune response to the pneumococcal polysaccharide vaccine in the elderly, samples from young adults and elderly were obtained before and one month after vaccination. The quantitative and qualitative response to the vaccine were measured by the ELISA and opsonophagocytic killing assay for eight vaccine type serotypes (4, 6B, 9V, 14, 18C, 19A, 19F, 23F) and one vaccine-related serotype (6A).
The response to the pneumococcal polysaccharide vaccine showed a similar response between adults and elderly when evaluated by the ELISA, however the functional activity of the antibodies elicited after vaccination were lower in the elderly group for more than half of the serotypes evaluated. In comparison of the antibody needed for 1:8 opsonic titer, more antibodies were needed in the elderly for serotypes Pn 4, 19F, 23F and 6A, suggesting the functional activity of antibody detected by the ELISA was lower in the elderly compared with the adult group for these serotypes. As for subjects with an opsonic titer <8 after vaccination, only one subject each for serotypes Pn 4, 9V and 6A were found in the adult group. However, up to 10 (30.3%) of the subjects did not show opsonic activity after vaccination in the elderly group for serotypes Pn 4, 9V, 14, 19A and 6A.
Although the amount of antibodies elicited were similar between the two age groups, distinct differences in function were noted. This report highlights the importance of a quantitative and qualitative evaluation of the immunogenic response to the PPV in the elderly age group.
This trial is registered with Clinicaltrials.gov. Registration number NCT00964769.
肺炎链球菌是导致老年人发病和死亡的主要原因。为了预防侵袭性肺炎球菌病，建议 65 岁以上人群接种 23 价肺炎球菌多糖疫苗（PPV）。尽管已有研究报道称，该疫苗可使普通老年人群的侵袭性疾病发生率降低 50-80%，但对于该疫苗在老年人中的有效性仍存在争议。
为评估肺炎球菌多糖疫苗在老年人中的免疫反应，在接种疫苗前后分别从年轻成年人和老年人中采集样本。通过 ELISA 和调理吞噬杀菌试验，对 8 种疫苗型血清型（4、6B、9V、14、18C、19A、19F、23F）和 1 种疫苗相关血清型（6A）进行了疫苗的定量和定性反应的测量。
通过 ELISA 评估，成人和老年人对肺炎球菌多糖疫苗的反应相似，但在评估的大多数血清型中，接种疫苗后产生的抗体的功能活性在老年人组中较低。与 1:8 调理噬菌作用滴度所需的抗体相比，老年人对血清型 Pn 4、19F、23F 和 6A 所需的抗体更多，这表明与成人组相比，ELISA 检测到的抗体功能活性在老年人中较低。对于接种后调理噬菌作用滴度<8 的受试者，仅在成人组的血清型 Pn 4、9V 和 6A 中发现了各 1 例。然而，在老年人组中，有高达 10 例（30.3%）的受试者在接种疫苗后对血清型 Pn 4、9V、14、19A 和 6A 无调理活性。
尽管两组之间产生的抗体数量相似，但功能上存在明显差异。本报告强调了对老年人进行 PPV 免疫原性反应的定量和定性评估的重要性。
本试验在 Clinicaltrials.gov 上注册。注册号：NCT00964769。
