Palazzo Raffaella, Carollo Maria, Bianco Manuela, Fedele Giorgio, Schiavoni Ilaria, Pandolfi Elisabetta, Villani Alberto, Tozzi Alberto E, Mascart Françoise, Ausiello Clara M
Anti-Infectious Immunity Unit, Department of Infectious, Parasitic and immune-mediated Diseases, Istituto Superiore di Sanità, Rome, Italy.
Epidemiology Unit, Research Center, Ospedale Pediatrico Bambino Gesù, IRCSS, Roma, Italy.
New Microbiol. 2016 Jan;39(1):35-47.
The resurgence of pertussis suggests the need for greater efforts to understand the long-lasting protective responses induced by vaccination. In this paper we dissect the persistence of T memory responses induced by primary vaccination with two different acellular pertussis (aP) vaccines, hexavalent Hexavac® vaccine (Hexavac) (Sanofi Pasteur MSD) and Infanrix hexa® (Infanrix) (Glaxo-SmithKline Biologicals). We evaluated magnitude and duration of T-cell responses to pertussis toxin (PT) by measuring T-cell proliferation, cytokines (IL-2 and IFNγ) production and memory subsets in two groups of children 5 years after primary vaccination. Some of the enrolled children received only primary vaccination, while others had the pre-school boost dose. Positive T-cell responses to PT were detected in 36% of children. Percentage of responsive children, T-cell proliferation and CD4IL-2+ cells were significantly higher in the children primed with Hexavac than in those who received Infanrix vaccine. No major effects of the boost on PT-specific proliferation were observed. Overall, our data documented a persistence of T-cell memory against PT in a minor fraction of children 5 years after primary vaccination. The different responses induced by Hexavac and Infanrix vaccine could rely on differences in PT inactivation process or excipients/adjuvants formulations.
百日咳的再度流行表明，需要做出更大努力来了解疫苗接种所诱导的持久保护性反应。在本文中，我们剖析了用两种不同的无细胞百日咳（aP）疫苗，即六价百白破疫苗Hexavac®（Hexavac）（赛诺菲巴斯德默克公司）和吸附无细胞百白破灭活脊髓灰质炎和b型流感嗜血杆菌联合疫苗Infanrix hexa®（Infanrix）（葛兰素史克生物制品公司）进行初次疫苗接种后T记忆反应的持续性。我们通过测量初次疫苗接种5年后两组儿童对百日咳毒素（PT）的T细胞增殖、细胞因子（IL-2和IFNγ）产生及记忆亚群，评估了T细胞对PT反应的强度和持续时间。部分入组儿童仅接受了初次疫苗接种，而其他儿童还接受了学龄前加强剂量接种。在36%的儿童中检测到了对PT的阳性T细胞反应。用Hexavac免疫的儿童中反应性儿童的百分比、T细胞增殖及CD4IL-2+细胞显著高于接受Infanrix疫苗的儿童。未观察到加强剂量对PT特异性增殖有重大影响。总体而言，我们的数据证明了初次疫苗接种5年后一小部分儿童中存在针对PT的T细胞记忆持续性。Hexavac和Infanrix疫苗所诱导的不同反应可能取决于PT灭活过程或辅料/佐剂配方的差异。
