The novel immunomodulatory biologic LMWF5A for pharmacological attenuation of the "cytokine storm" in COVID-19 patients: a hypothesis

Correlation of covid-19 and Guillain-Barré syndrome: A Mechanistic Perspective

Aims

Coronaviruses, SARS-CoV-2 particles are spherical and have proteins called spikes that stick out on the surface. COVID-19 most commonly affects the respiratory system, but various clinical manifestations on coronavirus have revealed their potential neurotropism. The neuroinvasive affinity of Coronavirus infections has been reported nearly for all the β Coronavirus infections, including MERS-CoV, SARS-CoV, HCoV-OC43 and HEV. Coronavirus invasion occurs through hypoxia injury, immune injury, ACE2, and direct infection. The pathophysiology of SARS-CoV-2 and other human Coronaviruses reveals the possible mechanisms of neurodegeneration.

Methods

A systematic literature review carried out from various search engines like Scopus, PubMed, Medline, and Elsevier for investigating the therapeutic perspective of association between Covid-19 and Guillain-Barré syndrome.

Results

SARS-CoV-2 uses angiotensin-converting enzyme 2 as its entry receptor and enters the central nervous system through a Blood-brain barrier constituted of inflammatory mediators, direct infection of the endothelial cells, or endothelial injury. Guillain-Barré syndrome is an autoimmune disease that injures and attacks the nerves in the peripheral nervous system. Studies suggest that the virus can infect peripheral neurons to cause direct damage through various mechanisms, including direct damage by cytokine-related injury, ACE2 receptors, and the sequelae of hypoxia.

Conclusion

we have discussed the possible mechanisms between neuroinvasion of SARs-cov2 and Guillain-barre syndrome.

A Novel CD206 Targeting Peptide Inhibits Bleomycin-Induced Pulmonary Fibrosis in Mice

Activated M2-polarized macrophages are drivers of pulmonary fibrosis in several clinical scenarios, including Idiopathic Pulmonary Fibrosis (IPF). In this study, we investigated the effects of targeting the CD206 receptor in M2-like macrophages with a novel synthetic analogue of a naturally occurring Host Defense Peptide (HDP), RP-832c, to decrease profibrotic cytokines. RP-832c selectively binds to CD206 on M2-polarized bone marrow-derived macrophages (BMDM) in vitro, resulting in a time-dependent decrease in CD206 expression and a transient increase in M1-macrophage marker TNF-α. To elucidate the antifibrotic effects of RP-832c, we used a murine model of bleomycin (BLM)-induced early-stage pulmonary fibrosis. RP-832c significantly reduced fibrosis in a dose-dependent manner, and decreased CD206, TGF-β1, and α-SMA expression in mouse lungs. Similarly, in an established model of lung fibrosis, RP-832c significantly decreased lung fibrosis and significantly decreased inflammatory cytokines TNF-α, IL-6, IL-10, IFN-γ, CXCL1/2, and fibrosis markers TGF-β1 and MMP-13. In comparison with the FDA-approved drugs Nintedanib and Pirfenidone, RP-832c exhibited a similar reduction in fibrosis compared to Pirfenidone, and to a greater extent than Nintedanib, with no apparent toxicities observed. In summary, our findings showed that inhibiting the profibrotic alternatively activated M2-like macrophages using a novel peptide, RP-832c, could reduce BLM-induced pulmonary fibrosis in mice, warranting the therapeutic potential of this peptide for patients with pulmonary fibrosis.

The impact of immune dysfunction on perioperative complications in surgical COVID-19 patients: an imperative for early immunonutrition

Surgical patients with coronavirus disease 2019 (COVID-19) are vulnerable to increased perioperative complications and postoperative mortality, independent of the risk for contracting COVID-19 pneumonia after endotracheal intubation for general anesthesia. The presumed root cause of postoperative infections, microvascular soft tissue injuries and thromboembolic complications is largely attributed to the profound immune dysfunction induced by COVID-19 as a result of complement activation and the "cytokine storm". The empirical therapy with anti-inflammatory agents has been shown to attenuate some of the adverse effects of systemic hyperinflammation in COVID-19 patients. In addition, the proactive concept of "immunonutrition" may represent a new promising avenue for mitigating the complex immune dysregulation in COVID-19 and thereby reduce the rates of surgical complications and postoperative mortality. This letter provides a narrative summary of the current state-of-the-art in the field of immunonutrition as it pertains to surgical patient safety in COVID-19 patients.

Bioprospecting of microalgae metabolites against cytokine storm syndrome during COVID-19

In viral respiratory infections, disrupted pathophysiological outcomes have been attributed to hyper-activated and unresolved inflammation responses of the immune system. Integration between available drugs and natural therapeutics have reported benefits in relieving inflammation-related physiological outcomes and microalgae may be a feasible source from which to draw from against future coronavirus-infections. Microalgae represent a large and diverse source of chemically functional compounds such as carotenoids and lipids that possess various bioactivities, including anti-inflammatory properties. Therefore in this paper, some implicated pathways causing inflammation in viral respiratory infections are discussed and juxtaposed along with available research done on several microalgal metabolites. Additionally, the therapeutic properties of some known anti-inflammatory, antioxidant and immunomodulating compounds sourced from microalgae are reported for added clarity.

A Randomized Controlled Trial to Evaluate the Safety and Efficacy of a Novel Inhaled Biologic Therapeutic in Adults with Respiratory Distress Secondary to COVID-19 Infection

INTRODUCTION

Inhaled therapeutics may act to directly target and attenuate lung inflammation due to COVID-19. An inhalation form of a novel biologic drug, AMP5A, is being developed as an immunomodulatory agent to treat dysregulated immune responses and is being studied in hospitalized patients to treat respiratory complications due to COVID-19.

METHODS

A randomized, controlled, phase I trial was conducted to evaluate hospitalized adults with respiratory distress secondary to COVID-19. Patients received the standard care (SOC) for COVID-19, including respiratory therapy, corticosteroids, and antiviral therapies such as remdesivir. Patients were randomized 1:1 to inhalation treatment with AMP5A as an adjunct to SOC or to SOC alone (control). AMP5A was administered via inhalation daily for 5 days via hand-held nebulizer, non-invasive ventilator, or mechanical ventilation. Safety and clinical efficacy endpoints were evaluated.

RESULTS

Forty subjects were enrolled and randomized (n = 19 AMP5A, n = 21 control). Remdesivir was used in fewer AMP5A subjects (26%) than control (52%), and dexamethasone was administered for most subjects (84% AMP5A, 71% control). The study met its primary endpoint with no AMP5A treatment-related adverse events (AEs), and the incidence and severity of AEs were comparable between groups: 18 AEs for control (8 mild, 1 moderate, 9 severe) and 19 AEs for AMP5A (7 mild, 7 moderate, 5 severe). Notably, subjects treated with AMP5A had fewer deaths (5% vs. 24%), shorter hospital stay (8 days vs. 12 days), fewer ICU admissions (21% vs. 33%), and a greater proportion with improved clinical outcomes than control.

CONCLUSION

The phase I clinical results indicate inhaled AMP5A is safe, is well tolerated, and could lead to fewer patients experiencing deterioration or death. Based on the treatment effect (i.e., reduced mortality), a phase II trial has been initiated.

TRIAL REGISTRATION

Clinicaltrials.gov identifier: NCT04606784.

A Combination of α-Lipoic Acid (ALA) and Palmitoylethanolamide (PEA) Blocks Endotoxin-Induced Oxidative Stress and Cytokine Storm: A Possible Intervention for COVID-19

The global scientific community is striving to understand the pathophysiological mechanisms and develop effective therapeutic strategies for COVID-19. Despite overwhelming data, there is limited knowledge about the molecular mechanisms involved in the prominent cytokine storm syndrome and multiple organ failure and fatality in COVID-19 cases. The aim of this work is to investigate the possible role of of α-lipoic acid (ALA) and palmitoylethanolamide (PEA), in countering the mechanisms in overproduction of reactive oxygen species (ROS), and inflammatory cytokines. An in vitro model of lipopolysaccharide (LPS)-stimulated human epithelial lung cells that mimics the pathogen-associated molecular pattern and reproduces the cell signaling pathways in cytokine storm syndrome has been used. In this model of acute lung injury, the combination effects of ALAPEA, administered before and after LPS injury, were investigated. Our data demonstrated that a combination of 50 µM ALA + 5 µM PEA can reduce ROS and nitric oxide (NO) levels modulating the major cytokines involved on COVID-19 infection when administered either before or after LPS-induced damage. The best outcome was observed when administered after LPS, thus reinforcing the hypothesis that ALA combined with PEA to modulate the key point of cytokine storm syndrome. This work supports for the first time that the combination of ALA with PEA may represent a novel intervention strategy to counteract inflammatory damage related to COVID-19 by restoring the cascade activation of the immune response and acting as a powerful antioxidant.

JAK-STAT Pathway Inhibition and their Implications in COVID-19 Therapy

As the incidence of COVID-19 increases with time, more and more efforts are made to pave a way out for the therapeutic strategies to deal with the disease progression. Inflammation being a significant influencer in COVID-19 patients, it drives our focus onto the signaling cascades of the JAK/STAT pathway. JAK phosphorylation mediated by cytokine receptor activation leads to phosphorylation of STATs that translocate into the nucleus to translate for inflammatory mediators. The SARS-CoV-2 structural proteins like spike, nucleocapsid, membrane and envelope proteins along with the non- structural proteins 1-16 including proteases like 3CL pro and PLpro promote its entry and survival in hosts. The SARS-CoV-2 infection triggers inflammation via the JAK/STAT pathway leading to recruitment of pneumocytes, endothelial cells, macrophages, monocytes, lymphocytes, natural killer cells and dendritic cells progressing towards cytokine storm. This produces various inflammatory markers in the host that determine the disease severity. The JAK/STAT signaling also mediates immune responses via B cell and T cell differentiation.With an attempt to reduce excessive inflammation, JAK/STAT inhibitors like Ruxolitinib, Baricitinib, Tofacitinib have been employed that mediate its actions via suppressors of cytokine signaling, cytokine inducible SH2 containing protein, Protein inhibitor of activated STAT and protein tyrosine phosphatases. Even though they are implicated with multiple adverse effects, the regulatory authorities have supported its use, and numerous clinical trials are in progress to prove their safety and efficacy. On the contrary, the exact mechanism of JAK/STAT inhibition at molecular levels remains speculative for which further investigations are required.

SARS-CoV-2: Pathogenesis, Molecular Targets and Experimental Models

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a recent pandemic outbreak threatening human beings worldwide. This novel coronavirus disease-19 (COVID-19) infection causes severe morbidity and mortality and rapidly spreading across the countries. Therefore, there is an urgent need for basic fundamental research to understand the pathogenesis and druggable molecular targets of SARS-CoV-2. Recent sequencing data of the viral genome and X-ray crystallographic data of the viral proteins illustrate potential molecular targets that need to be investigated for structure-based drug design. Further, the SARS-CoV-2 viral pathogen isolated from clinical samples needs to be cultivated and titrated. All of these scenarios demand suitable laboratory experimental models. The experimental models should mimic the viral life cycle as it happens in the human lung epithelial cells. Recently, researchers employing primary human lung epithelial cells, intestinal epithelial cells, experimental cell lines like Vero cells, CaCo-2 cells, HEK-293, H1299, Calu-3 for understanding viral titer values. The human iPSC-derived lung organoids, small intestinal organoids, and blood vessel organoids increase interest among researchers to understand SARS-CoV-2 biology and treatment outcome. The SARS-CoV-2 enters the human lung epithelial cells using viral Spike (S1) protein and human angiotensin-converting enzyme 2 (ACE-2) receptor. The laboratory mouse show poor ACE-2 expression and thereby inefficient SARS-CoV-2 infection. Therefore, there was an urgent need to develop transgenic hACE-2 mouse models to understand antiviral agents' therapeutic outcomes. This review highlighted the viral pathogenesis, potential druggable molecular targets, and suitable experimental models for basic fundamental research.

A Multifunctional Peptide From Bacillus Fermented Soybean for Effective Inhibition of SARS-CoV-2 S1 Receptor Binding Domain and Modulation of Toll Like Receptor 4: A Molecular Docking Study

Fermented soybean products are traditionally consumed and popular in many Asian countries and the northeastern part of India. To search for potential agents for the interruption of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Spike glycoprotein 1 (S1) and human angiotensin-converting enzyme 2 (ACE2) receptor interactions, the in silico antiviral prospective of peptides identified from the proteome of kinema was investigated. Soybean was fermented using Bacillus licheniformis KN1G, Bacillus amyloliquefaciens KN2G and two different strains of Bacillus subtilis (KN2B and KN2M). The peptides were screened in silico for possible antiviral activity using two different web servers (AVPpred and meta-iAVP), and binding interactions of selected 44 peptides were further explored against the receptor-binding domain (RBD) of the S1 protein (PDB ID: 6M0J) by molecular docking using ZDOCK. The results showed that a peptide ALPEEVIQHTFNLKSQ (P13) belonging to B. licheniformis KN1G fermented kinema was able to make contacts with the binding motif of RBD by blocking specific residues designated as critical (GLN493, ASN501) in the binding of human angiotensin-converting enzyme 2 (ACE2) cell receptor. The selected peptide was also observed to have a significant affinity towards human toll like receptor 4 (TLR4)/Myeloid Differentiation factor 2 (MD2) (PDB ID: 3FXI) complex known for its essential role in cytokine storm. The energy properties of the docked complexes were analyzed through the Generalized Born model and Solvent Accessibility method (MM/GBSA) using HawkDock server. The results showed peptidyl amino acids GLU5, GLN8, PHE11, and LEU13 contributed most to P13-RBD binding. Similarly, ARG90, PHE121, LEU61, PHE126, and ILE94 were appeared to be significant in P13-TLR4/MD2 complex. The findings of the study suggest that the peptides from fermented soy prepared using B. licheniformis KN1G have better potential to be used as antiviral agents. The specific peptide ALPEEVIQHTFNLKSQ could be synthesized and used in combination with experimental studies to validate its effect on SARS-CoV-2-hACE2 interaction and modulation of TLR4 activity. Subsequently, the protein hydrolysate comprising these peptides could be used as prophylaxis against viral diseases, including COVID-19.

Cellular and Molecular Immunology Approaches for the Development of Immunotherapies against the New Coronavirus (SARS-CoV-2): Challenges to Near-Future Breakthroughs

The severe acute respiratory syndrome caused by the new coronavirus (SARS-CoV-2), termed COVID-19, has been highlighted as the most important infectious disease of our time, without a vaccine and treatment available until this moment, with a big impact on health systems worldwide, and with high mortality rates associated with respiratory viral disease. The medical and scientific communities have also been confronted by an urgent need to better understand the mechanism of host-virus interaction aimed at developing therapies and vaccines. Since this viral disease can trigger a strong innate immune response, causing severe damage to the pulmonary tract, immunotherapies have also been explored as a means to verify the immunomodulatory effect and improve clinical outcomes, whilst the comprehensive COVID-19 immunology still remains under investigation. In this review, both cellular and molecular immunopathology as well as hemostatic disorders induced by SARS-CoV-2 are summarized. The immunotherapeutic approaches based on the most recent clinical and nonclinical studies, emphasizing their effects for the treatment of COVID-19, are also addressed. The information presented elucidates helpful insights aiming at filling the knowledge gaps around promising immunotherapies that attempt to control the dysfunction of host factors during the course of this infectious viral disease.

A Novel CD206 Targeting Peptide Inhibits Bleomycin Induced Pulmonary Fibrosis in Mice

Activated M2 polarized macrophages are drivers of pulmonary fibrosis in several clinical scenarios such as Acute Respiratory Disease Syndrome (ARDS) and Idiopathic Pulmonary Fibrosis (IPF), through the production of inflammatory and fibrosis-inducing cytokines. In this study, we investigated the effect of targeting the CD206 receptor with a novel fragment of a Host Defense Peptide (HDP), RP-832c to decrease cytokines that cause fibrosis. RP-832c selectively binds to CD206 on M2 polarized bone marrow derived macrophages (BMDM) in vitro , resulting in a time-dependent decrease in CD206 expression, and a transient increase in M1 marker TNFα, which resolves over a 24hr period. To elucidate the antifibrotic effect of RP-832c, we used a murine model of bleomycin (BLM) -induced early-stage pulmonary fibrosis. RP-832c significantly reduced bleomycin-induced fibrosis in a dosage dependent manner, as well as decreased CD206, TGF-β1 and α-SMA expression in mouse lungs. Interestingly we did not observe any changes in the resident alveolar macrophage marker CD170 expression. Similarly, in an established model of lung fibrosis, RP-832c significantly decreased fibrosis in the lung, as well as significantly decreased inflammatory cytokines TNFα, IL-6, IL-10, INF-γ, CXCL1/2, and fibrosis markers TGF-β1 and MMP-13. In comparison with FDA approved drugs, Nintedanib and Pirfenidone, RP-832c exhibited a similar reduction in fibrosis compared to Pirfenidone, and to a greater extent than Nintedanib, with no apparent toxicities observed on body weight or blood chemistry. In summary, RP-832c is a potential agent to mitigate the overactivity of M2 macrophages in pathogenesis several pulmonary fibrotic diseases, including SARS-CoV-2 induced lung fibrosis.