Department of Histology, Faculty of Medicine Jagiellonian University Medical College, Cracow, Poland.
J Physiol Pharmacol. 2020 Apr;71(2). doi: 10.26402/jpp.2020.2.11. Epub 2020 Aug 8.
Matrix metalloproteinases (MMPs) regulated by their tissue inhibitors (TIMPs) play a significant role in the pathogenesis of multiple sclerosis (MS) and its mouse model, experimental autoimmune encephalomyelitis (EAE), as they degrade extracellular matrix including vascular basal laminae and by damaging blood-brain barrier (BBB) facilitate transmigration of immune cells into the central nervous system. MMPs are also involved in destruction of myelin sheaths, leading to axonal and neuronal loss. The aim of the present study was to assess whether natalizumab, a transmigration-inhibiting monoclonal antibody against α4β1 integrin, influences expression of MMPs and TIMPs in the central nervous system of mice with EAE. MMP-2 and MMP-9, their respective inhibitors TIMP-2 and TIMP-1 and laminin were assessed by quantitative immunohistochemistry in the spinal cord cryosections of C57BL/6 mice with EAE in the successive phases of the disease (onset, peak and chronic). The percentage of immunopositive areas were calculated in sections encompassing the whole spinal cord cross-sectional area occupied by the gray and white matter. Results obtained in animals administered with 5 mg/kg natalizumab were compared with those collected from control mice receiving 5 mg/kg IgG. Both studied MMPs and both TIMPs were upregulated in control EAE mice. Natalizumab treatment significantly reduced expression of MMPs and increased expression of TIMPs in the peak and chronic phases of the disease. This effect was accompanied by inhibition of laminin degradation in the vascular basal laminae and reduction of inflammatory infiltration. Results of this study demonstrate that in addition to its well known anti-integrin activity counteracting transmigration of immune cells into the central nervous system, natalizumab strengthens this effect by its probably indirect influence on MMPs and TIMPs leading to protection of blood-brain barrier integrity.
基质金属蛋白酶（MMPs）及其组织抑制剂（TIMPs）在多发性硬化症（MS）及其小鼠模型实验性自身免疫性脑脊髓炎（EAE）的发病机制中起着重要作用，因为它们降解细胞外基质，包括血管基底膜，并通过破坏血脑屏障（BBB）促进免疫细胞向中枢神经系统迁移。MMPs 还参与髓鞘的破坏，导致轴突和神经元的损失。本研究旨在评估迁移抑制性单克隆抗体针对 α4β1 整合素的那他珠单抗是否会影响 EAE 小鼠中枢神经系统中 MMPs 和 TIMPs 的表达。通过定量免疫组织化学方法在 EAE 后 C57BL/6 小鼠的脊髓冷冻切片中评估 MMP-2 和 MMP-9、它们各自的抑制剂 TIMP-2 和 TIMP-1 以及层粘连蛋白。在疾病的各个阶段（发作、高峰和慢性期），在包括灰质和白质占据的整个脊髓横截面积的切片中计算免疫阳性区域的百分比。与接受 5mg/kg IgG 的对照小鼠相比，比较了给予 5mg/kg 那他珠单抗的动物的结果。在对照 EAE 小鼠中，两种研究的 MMPs 和两种 TIMPs 均上调。那他珠单抗治疗在疾病的高峰和慢性期显著降低 MMPs 的表达并增加 TIMPs 的表达。这种作用伴随着血管基底膜中层粘连蛋白降解的抑制和炎症浸润的减少。本研究的结果表明，除了众所周知的抗整合素活性，抑制免疫细胞向中枢神经系统的迁移外，那他珠单抗还通过可能间接影响 MMPs 和 TIMPs 来增强这种作用，从而保护血脑屏障的完整性。
