SARS-CoV-2 meta-interactome suggests disease-specific, autoimmune pathophysiologies and therapeutic targets.

Background: Severe coronavirus disease 2019 (COVID-19) is associated with multiple comorbidities and is characterized by an auto-aggressive inflammatory state leading to massive collateral damage. To identify preventive and therapeutic strategies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), it is important to ascertain the molecular interactions between virus and host, and how they translate into disease pathophysiology. Methods: We matched virus-human protein interactions of human coronaviruses and other respiratory viruses with lists of genes associated with autoimmune diseases and comorbidities associated to worse COVID-19 course. We then selected the genes included in the statistically significant intersection between SARS-CoV-2 network and disease associated gene sets, identifying a meta-interactome. We analyzed the meta-interactome genes expression in samples derived from lungs of infected humans, and their regulation by IFN-β. Finally, we performed a drug repurposing screening to target the network's most critical nodes. Results: We found a significant enrichment of SARS-CoV-2 interactors in immunological pathways and a strong association with autoimmunity and three prognostically relevant conditions (type 2 diabetes, coronary artery diseases, asthma), that present more independent physiopathological subnetworks. We observed a reduced expression of meta-interactome genes in human lungs after SARS-CoV-2 infection, and a regulatory potential of type I interferons. We also underscored multiple repurposable drugs to tailor the therapeutic strategies. Conclusions: Our data underscored a plausible genetic background that may contribute to the distinct observed pathophysiologies of severe COVID-19. Also, these results may help identify the most promising therapeutic targets and treatments for this condition

Viruses and neuroinflammation in multiple sclerosis

In multiple sclerosis (MS), a relationship with viral infection has long been recognized, starting from clinical evidence of an association between infectious events and disease onset or relapse. Herpesviridae and human endogenous retroviruses (HERVs) are among the most studied viral families in MS. These exposures share the characteristic of being latent persisting infections with hidden or dormant phases that allow them to escape immune detection and reactivate upon exposure to several stimuli. Moreover, their preferential tropism for cells of the central nervous system (CNS) and immune system accounts for their plausible pathogenic role in neuroinflammation. Compartmentalized and persisting chronic inflammation within the CNS is a feature of MS, as compared with other forms of self-limiting demyelinating conditions. This has suggested the existence of a persistent agent (such as a latent virus) that sustains the pathogenic loop and determines consequent tissue damage, failure of reparative mechanisms, and accumulation of neurological deficits. This review aims to survey the literature on the relationship between viruses and MS, with special reference to the levels of complexity in the loop that can modify disease risk, namely non-genetic risk factors (including viral components) that interact with each other and with genetic variants, with possible effects on both the host and viral genome. We will also review the latest advances in therapeutic targeting virus-induced dysregulations in MS

Intestinal Permeability and Circulating CD161+CCR6+CD8+T Cells in Patients With Relapsing–Remitting Multiple Sclerosis Treated With Dimethylfumarate

Background: The changes of the gut-brain axis have been recently recognized as important components in multiple sclerosis (MS) pathogenesis. Objectives: To evaluate the effects of DMF on intestinal barrier permeability and mucosal immune responses. Methods: We investigated intestinal permeability (IP) and circulating CD161+CCR6+CD8+T cells in 25 patients with MS, who met eligibility criteria for dimethyl-fumarate (DMF) treatment. These data, together with clinical/MRI parameters, were studied at three time-points: baseline (before therapy), after one (T1) and 9 months (T2) of treatment. Results: At baseline 16 patients (64%) showed altered IP, while 14 cases (56%) showed active MRI. During DMF therapy we found the expected decrease of disease activity at MRI compared to T0 (6/25 at T1, p = 0.035 and 3/25 at T2, p < 0.00), and a reduction in the percentage of CD161+CCR6+CD8+ T cells (16/23 at T2; p < 0.001). The effects of DMF on gut barrier alterations was variable, without a clear longitudinal pattern, while we found significant relationships between IP changes and drop of MRI activity (p = 0.04) and circulating CD161+CCr6+CD8+ T cells (p = 0.023). Conclusions: The gut barrier is frequently altered in MS, and the CD161+ CCR6+CD8+ T cell-subset shows dynamics which correlate with disease course and therapy