Department of Pediatrics, Neonatal Division of Medicine, Federal University of São Paulo, São Paulo, SP, Brazil.
Vaccine. 2012 Oct 12;30(46):6521-6. doi: 10.1016/j.vaccine.2012.08.056. Epub 2012 Sep 6.
To compare humoral and cellular immune responses to tetanus booster vaccination in infants born prematurely with those born at full term and identify factors associated with the humoral response.
A prospective study was carried out on children born prematurely and with a birth weight <1500g and with infants born at full term. At 15 months (pre-vaccination) and 18 months (post-vaccination), anti-tetanus antibodies were measured by ELISA; the intracellular interferon-gamma percentages of CD4+ T and CD8+ T cells after in vitro stimulation with tetanus toxoid were determined by flow cytometry. Chi-squared or Fisher's exact test was used to compare categorical variables. Student's t-test or Mann-Whitney test was used to compare numerical variables. Regression analysis was performed to determine factors associated with humoral immunity. Statistical significance was considered if p<0.05.
Sixty-four premature and 54 full-term infants were studied. The proportion of children immune against tetanus at 15 and 18 months was similar in both groups. The geometric mean of the antibodies was lower among the premature children at 15 months (p=0.025) and was similar in both groups at 18 months (p=0.852). The percentages of CD4+ and CD8+ T cells expressing intracellular IFN-γ were similar in both groups at 15 and 18 months. Gestational age <32 weeks was associated with a reduction of -0.116IU/mL in the level of antibodies at 15 months. Breastfeeding >6 months was associated with a 3.5-fold greater chance of optimal protective (≥0.1IU/mL) antibody level against tetanus at 15 months and an increase of 0.956IU/mL in the level of antibodies at 18 months.
Humoral and cellular response following a tetanus booster was similar in both groups. Premature infants exhibited lower levels of anti-tetanus antibodies at 15 months of age, with the lowest levels in those born at a gestational age of less than 32 weeks. Breastfeeding was associated with greater levels of antibody against tetanus.
比较早产儿和足月出生婴儿破伤风加强免疫接种后的体液和细胞免疫反应，并确定与体液反应相关的因素。
对出生体重<1500g的早产儿和足月出生的婴儿进行前瞻性研究。在 15 个月（接种前）和 18 个月（接种后），通过 ELISA 测量抗破伤风抗体；通过流式细胞术检测破伤风类毒素体外刺激后 CD4+T 和 CD8+T 细胞内干扰素-γ的百分比。使用卡方检验或 Fisher 确切概率法比较分类变量。使用 Student's t 检验或 Mann-Whitney 检验比较数值变量。采用回归分析确定与体液免疫相关的因素。如果 p<0.05，则认为具有统计学意义。
共纳入 64 例早产儿和 54 例足月婴儿进行研究。两组儿童在 15 个月和 18 个月时对破伤风的免疫比例相似。早产儿在 15 个月时的抗体几何均数较低（p=0.025），而两组在 18 个月时相似（p=0.852）。两组儿童在 15 个月和 18 个月时 CD4+和 CD8+T 细胞表达细胞内 IFN-γ的百分比相似。<32 周的胎龄与 15 个月时抗体水平降低 -0.116IU/mL 相关。母乳喂养>6 个月与 15 个月时产生最佳保护（≥0.1IU/mL）破伤风抗体水平的几率增加 3.5 倍相关，并且 18 个月时抗体水平增加 0.956IU/mL。
两组儿童破伤风加强免疫后的体液和细胞反应相似。早产儿在 15 个月时破伤风抗体水平较低，胎龄<32 周的早产儿水平最低。母乳喂养与破伤风抗体水平较高相关。
