BACKGROUND There is a paucity of human data on exposure to blast traumatic brain injury (bTBI) and the corresponding systemic cytokine immune response at later time points (i.e., months, years) post-injury. METHODS We conducted a repeated measures, case-control study, examining associations of serum levels of pro- and anti-inflammatory cytokines, measured both pre- and post-deployment with having mild and moderate/severe bTBI. Utilizing serum from the Department of Defense Serum Repository cytokines were measured via an ELISA-based array for 15 cytokines. We compared pre- vs. post-levels among mild cases, moderate/severe cases, and controls and carried out case-control comparisons, using paired t- tests and generalized linear models. RESULTS The average time between bTBI and post-deployment/bTBI serum among cases was 315.8 days. From pre- to post-deployment/bTBI, levels of interleukin 8 (IL-8) were decreased among both mild cases (μ = - 83.43 pg/ml; s.e. = 21.66) and moderate/severe cases (μ = - 107.67 pg/ml; s.e. = 28.74 pg/ml), while levels increased among controls (μ = 32.86 pg/ml; s.e. = 30.29). The same pattern occurred for matrix metallopeptidase 3 (MMP3), with levels decreasing for moderate/severe cases (μ = - 3369.24 pg/ml; s.e. = 1701.68) and increasing for controls (μ = 1859.60 pg/ml; s.e. = 1737.51) from pre- to post-deployment/bTBI. Evidence was also suggestive of case-control differences, from pre- to post-deployment/bTBI for interleukin 1 alpha (IL-1α), interleukin 4 (IL-4), and interleukin 6 (IL-6) among moderate/severe cases. CONCLUSION The findings of this longitudinal study indicate that in the chronic phase of bTBI, levels of IL-8 and MMP3 may be substantially lower than pre-injury. These results need confirmation in other studies, potentially those that account for treatment differences, which was not possible in our study.

中文翻译：

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爆炸性颅脑损伤和血清炎性细胞因子：美国军人中一项重复措施的病例对照研究。

背景技术在创伤后较晚的时间点（即，数月，数年），关于爆炸性脑损伤（bTBI）和相应的全身细胞因子免疫反应的暴露的人类数据很少。方法我们进行了一项重复措施，病例对照研究，检查血清中促炎和抗炎细胞因子水平的相关性，并在部署前和部署后对轻，中度/重度bTBI进行测量。通过基于ELISA的阵列对15种细胞因子进行测量，从国防部血清中获取血清库细胞因子。我们比较了轻度病例，中度/重度病例和对照之间的前后水平，并使用配对的t检验和广义线性模型进行了病例对照比较。结果病例间bTBI和展开后/ bTBI血清之间的平均时间为315.8天。从部署前到部署后/ bTBI，轻度病例（μ=-83.43 pg / ml； se = 21.66）和中度/重度病例（μ=-107.67 pg / ml）中白细胞介素8（IL-8）的水平均降低。 ml； se = 28.74 pg / ml），而对照组之间的水平有所增加（μ= 32.86 pg / ml； se = 30.29）。基质金属肽酶3（MMP3）发生了相同的模式，中/重度病例的水平降低（μ=-3369.24 pg / ml; se = 1701.68），而对照水平升高（μ= 1859.60 pg / ml; se = 1737.51）部署前/部署后/ bTBI。证据还表明，在中/重度病例中，从部署前/部署后/ bTBI到白细胞介素1 alpha（IL-1α），白细胞介素4（IL-4）和白细胞介素6（IL-6）的病例对照差异。 。结论这项纵向研究的结果表明，在bTBI的慢性期，IL-8和MMP3的水平可能大大低于损伤前。这些结果需要其他研究的证实，可能是那些解释治疗​​差异的结果，这在我们的研究中是不可能的。