男性性别决定了实验性中风后IL-17抗体治疗的长期神经保护效果

男性性别决定了实验性中风后IL-17抗体治疗的长期神经保护效果 (Male sex determines long-term neuroprotection of an Interleukin 17 antibody treatment after experimental stroke in aged mice)

引言

免疫系统的激活显著影响实验性中风模型中的缺血性组织损伤。激活的炎症级联反应中，γδ T细胞在缺血后脑中快速释放IL-17A，对于年轻雄性小鼠早期有害中性粒细胞浸润的放大至关重要。然而，其对长期中风结果的影响以及年龄和性别的效应仍然未知。因此，我们研究的目的是分析性别和年龄是否影响IL-17抗体（Ab）治疗在实验性中风中的效果。

方法

为了研究早期IL-17中和对长期结果的影响，我们在短暂性大脑中动脉阻塞（tMCAO）后1小时给12-14个月大的雄性或雌性小鼠施用IL-17Ab或IgG对照（20µg/kg体重），并在中风后的第3天评估病灶体积以及行为结果，跟踪至90天。我们通过流式细胞术和免疫组织化学分析了缺血后的炎症反应。为了揭示肠道微生物群对IL-17A+ γδ T细胞的影响，我们进行了微生物16S rRNA测序和粪便微生物移植（FMT）。

结果

IL-17中和在tMCAO后1小时显著减少了中风后的第3天的梗死体积，这在年长雄性小鼠中伴随着死亡率降低和90天后的神经功能改善，但在年长雌性小鼠中没有观察到类似效果。因此，年长雄性小鼠的大脑浸润的γδ T细胞在中风后第3天的IL-17A水平较年长雌性小鼠更高，并且在IL-17Ab治疗后，中性粒细胞浸润仅在年长雄性小鼠中减少。此外，16S rRNA测序揭示了一个不同的微生物谱，包括年长雄性小鼠的短链脂肪酸生产相关途径的减少。最后，年长雄性小鼠的粪便FMT在年轻雄性受体小鼠中诱导了更高的IL-17A水平，而年长雌性小鼠的粪便移植则没有这种效果，突显了微生物群的调节作用。

结论

IL-17中和改善了年长雄性小鼠的90天长期结果，但未对年长雌性小鼠产生相同效果，这与年长雄性小鼠的微生物谱强化了IL-17A轴的情况相关。这些发现突显了以IL-17A为中心的中风治疗的潜力，并强调了未来中风研究中考虑性别差异的重要性。

参考文献

• [1] Endres M, Moro MA, Nolte CH, Dames C, Buckwalter MS, Meisel A. Immune Pathways in Etiology, Acute Phase, and Chronic Sequelae of Ischemic Stroke. Circ Res. 2022;130(8):1167-86.
• [2] Shichita T, Sugiyama Y, Ooboshi H, Sugimori H, Nakagawa R, Takada I, Iwaki T, Okada Y, Iida M, Cua DJ, Iwakura Y, Yoshimura A. Pivotal role of cerebral interleukin-17-producing gammadeltaT cells in the delayed phase of ischemic brain injury. Nat Med. 2009;15(8):946-50.
• [3] Gelderblom M, Koch S, Strecker J-K, Jørgensen C, Garcia-Bonilla L, Ludewig P, Schädlich IS, Piepke M, Degenhardt K, Bernreuther C, Pinnschmidt H, Arumugam TV, Thomalla G, Faber C, Sedlacik J, Gerloff C, Minnerup J, Clausen BH, Anrather J, Magnus T. A preclinical randomized controlled multicenter trial of anti-interleukin-17A treatment for acute ischemic stroke. Brain Communications. 2023.

图表说明: 性别差异在IL-17A轴中决定了年长小鼠的中风后结果

• A：梗死体积（3天），B：生存率，C：神经评分（90天）
• D：IL-17A+ CNS γδ T细胞百分比（3天）
• E：IL-17Ab或IgG处理的年长雄性或雌性小鼠的大脑中性粒细胞计数/mm²（1天）
• F：年长雄性或雌性小鼠粪便内容物的16S rRNA测序主成分分析（PCA）
• G：16S rRNA测序途径分析
• H：年轻雄性小鼠在接受年长雄性、雌性或年轻雄性粪便FMT后的IL-17A+ CNS γδ T细胞百分比（3天）. //** P<0.05/0.01/0.001,
• A, D, E 采用未配对的Student's t检验，B 采用χ²检验，C 采用Mann-Whitney U检验，H 采用单因素方差分析（Sidak多重比较）。

Introduction

The activation of the immune system significantly impacts ischemic tissue damage in experimental stroke models1. Among the activated inflammatory cascades, the rapid release of IL-17A by γδ T cells in the post-ischemic brain is pivotal for the amplification of the early detrimental neutrophil infiltration in young male mice2,3. However, its influence on long-term stroke outcomes and the effects of age and sex remain unknown. Thus, the objectives of our study were to analyze whether sex and age influence the effect of an IL-17-Antibody (Ab) treatment in experimental stroke.

Methods

To investigate the effect of early IL-17 neutralization on long-term outcomes, we administered IL-17Ab or IgG control (20µg/kg body weight) to 12-14 month-old male or female mice 1h following transient middle cerebral artery occlusion (tMCAO) and assessed lesion volume at 3 days (d) and behavioral outcomes up to 90d post-stroke. We analyzed the post-ischemic inflammatory response using flow cytometry and immunohistochemistry. To decipher the influence of the gut microbiota on IL-17A+ γδ T cells, we performed microbial 16S rRNA sequencing and Fecal Microbial Transplantations (FMTs).

Results

IL-17-neutralization 1h post-tMCAO significantly reduces infarct volume 3d after stroke, which is accompanied by reduced mortality and improved neurological outcomes after 90d in aged male, but not in aged female mice (A-C). Accordingly, brain infiltrating γδ T cells from aged male mice show increased IL-17A levels 3d post-stroke compared to aged female mice, correlating with decreased neutrophil infiltration seen only in aged male mice after IL-17Ab treatment (D, E). Furthermore, 16S rRNAseq revealed a distinct microbial profile, including a decline in pathways linked to short-chain-fatty-acid production in aged male compared to aged female mice (F, G). Finally, FMTs of aged male stool induced higher IL-17A levels in CNS γδ T cells in young male recipient mice post-stroke compared to aged female stool transfers, highlighting the modulation by the microbiota (H).

Conclusion

IL-17 neutralization improves 90d long-term outcomes in aged male but not aged female mice, which is associated with a microbial profile strengthening the IL-17A axis in aged males. These findings highlight the potential of IL-17A-centered stroke therapies and underscore the importance of considering sex differences in future stroke studies.

Sex differences in the IL-17A axis determine post-stroke outcome in aged mice

• A Infarct volume 3d,
• B Survival and
• C Neuroscore 90d post-tMCAO of IL-17Ab or IgG treated aged male or female mice.
• D % IL-17A+ CNS γδ T cells 3d post-tMCAO.
• E Brain neutrophil counts/mm2 of IL-17Ab or IgG treated aged male or female mice 1d post-tMCAO.
• F PCA and
• G Pathway analysis of 16s rRNAseq of stool content of aged male or female mice.
• H % IL-17A+ CNS γδ T cells of young male mice after FMT of aged male, female or young male stool 3d post-tMCAO. //** P<0.05/0.01/0.001,
• A, D, E unpaired student's t-Test, B χ2-test, C Mann-Whitney U-test, H one-way ANOVA (Sidak‘s multiple comparison).

like unlike

点赞本文的读者

还没有人对此文章表态

本文有评论

没有评论

看文章，发评论，不要沉默