Rodríguez-Morales Jahir, Guartazaca-Guerrero Sebastián, Rizo-Téllez Salma A, Viurcos-Sanabria Rebeca, Barrón Eira Valeria, Hernández-Valencia Aldo F, Nava Porfirio, Escobedo Galileo, Carrillo-Ruiz José Damián, Méndez-García Lucía A
Neurosurgery Specialty, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico.
Neurology and Neurosurgery Unit, General Hospital of Mexico "Dr. Eduardo Liceaga", Mexico City 06720, Mexico.
Exp Neurobiol. 2022 Aug 31;31(4):270-276. doi: 10.5607/en21049.
Transsynaptic transport is the most accepted proposal to explain the SARS-CoV-2 infection of the CNS. Nevertheless, emerging evidence shows that neurons do not express the SARS-CoV-2 receptor ACE2, which highlights the importance of the blood-brain barrier (BBB) in preventing virus entry to the brain. In this study, we examine the presence of SARS-CoV-2 messenger ribonucleic acid (mRNA) and the cytokine profile in cerebrospinal fluids (CSF) from two patients with a brain tumor and COVID-19. To determine the BBB damage, we evaluate the Q- albumin index, which is an indirect parameter to assess the permeability of this structure. The Q-albumin index of the patient with an intraventricular brain tumor suggests that the BBB is undamaged, preventing the passage of SARS-CoV-2 and pro-inflammatory molecules. The development of brain tumors that disrupt the BBB (measured by the Q-albumin index), in this case, a petroclival meningioma (Case 1), allows the free passage of the SARS-CoV-2 virus and probably lets the free transit of pro-inflammatory molecules to the CNS, which leads to a possible activation of the microglia (astrogliosis) and an exacerbated immune response represented by IL-13, IFN-γ, and IL-2 trying to inhibit both the infection and the carcinogenic process.
跨突触运输是解释SARS-CoV-2感染中枢神经系统最被认可的假说。然而，新出现的证据表明神经元不表达SARS-CoV-2受体ACE2，这凸显了血脑屏障（BBB）在阻止病毒进入大脑方面的重要性。在本研究中，我们检测了两名患有脑肿瘤且感染新冠病毒患者脑脊液（CSF）中SARS-CoV-2信使核糖核酸（mRNA）的存在情况及细胞因子谱。为了确定血脑屏障的损伤情况，我们评估了Q-白蛋白指数，这是评估该结构通透性的一个间接参数。患有脑室内脑肿瘤患者的Q-白蛋白指数表明血脑屏障未受损，可阻止SARS-CoV-2和促炎分子通过。在这种情况下，即岩斜脑膜瘤（病例1），破坏血脑屏障的脑肿瘤（通过Q-白蛋白指数衡量）的发展使得SARS-CoV-2病毒能够自由通过，并且可能使促炎分子自由进入中枢神经系统，这可能导致小胶质细胞激活（星形胶质细胞增生）以及由IL-13、IFN-γ和IL-2代表的加剧的免疫反应，试图抑制感染和致癌过程。
