Perspectives on anti-IL-1 inhibitors as potential therapeutic interventions for severe COVID-19

An Update on SARS-CoV-2 Clinical Trial Results-What We Can Learn for the Next Pandemic

The coronavirus disease 2019 (COVID-19) pandemic has claimed over 7 million lives worldwide, providing a stark reminder of the importance of pandemic preparedness. Due to the lack of approved antiviral drugs effective against coronaviruses at the start of the pandemic, the world largely relied on repurposed efforts. Here, we summarise results from randomised controlled trials to date, as well as selected in vitro data of directly acting antivirals, host-targeting antivirals, and immunomodulatory drugs. Overall, repurposing efforts evaluating directly acting antivirals targeting other viral families were largely unsuccessful, whereas several immunomodulatory drugs led to clinical improvement in hospitalised patients with severe disease. In addition, accelerated drug discovery efforts during the pandemic progressed to multiple novel directly acting antivirals with clinical efficacy, including small molecule inhibitors and monoclonal antibodies. We argue that large-scale investment is required to prepare for future pandemics; both to develop an arsenal of broad-spectrum antivirals beyond coronaviruses and build worldwide clinical trial networks that can be rapidly utilised.

5-Fluoro/(trifluoromethoxy)-2-indolinone derivatives with anti-interleukin-1 activity

The pro-inflammatory cytokine interleukin-1 (IL-1) drives the pathogenesis of several inflammatory diseases. Recent studies have revealed that 2-indolinones can modulate cytokine responses. Therefore, we screened several 2-indolinone derivatives in preliminary studies to develop agents with anti-IL-1 activity. First, the putative efficacies and binding interactions of 2-indolinones were evaluated by docking studies. Second, previously synthesized 5-fluoro/(trifluoromethoxy)-1H-indole-2,3-dione 3-(4-phenylthiosemicarbazones) (compounds 47-69) which had the highest inhibitory effect in the screening were evaluated for inhibitory effects on the IL-1 receptor (IL-1R). Compounds 52 (IC50  = 0.09 µM) and 65 (IC50  = 0.07 µM) were selected as lead compounds for the subsequent synthesis of new derivatives. The novel 5-fluoro/(trifluoromethoxy)-1H-indole-2,3-dione 3-(4-phenylthiosemicarbazones) (compounds 70-116) were designed, synthesized, and in vitro studies were completed. The compounds 76, 78, 81, 91, 100, 105, and 107 tested showed nontoxic inhibitory effects on IL-1R-dependent responses in the range of 0.01-0.06 µM and stronger than the lead compounds 52 and 65. In vitro and in silico findings showed that compounds 78 (IC50  = 0.01 µM) and 81 (IC50  = 0.02 µM) had the strongest IL-1R inhibitory effects and the most favorable drug-like properties. Molecular modeling studies of the compounds 78 and 81 were carried out to determine the possible binding interactions at the active site of the IL-1R.

Adipose tissue-derived mesenchymal stromal cells attenuate acute lung injury induced by trauma and haemorrhagic shock

BACKGROUND

Mesenchymal stromal cells (MSCs) have shown promising therapeutic options for acute lung injury (ALI) caused by multiple factors. Here, we evaluated the therapeutic potential of adipose tissue-derived mesenchymal stromal cells (ADSCs) in trauma and hemorrhagic shock (THS)-induced ALI.

METHODS

ALI model induced by THS was constructed by fractures plus abdominal trauma plus acute hemorrhage plus fluid resuscitation. The ADSCs group rats were generated by injecting 2 × 106 ADSCs at 0 and 1 h after THS. The sham, ALI, and ADSCs group rats were sacrificed at 24 h after resuscitation. The changes in lung histopathology, total protein in bronchoalveolar lavage fluid (BALF), mRNA expression of pro-inflammatory/anti-inflammatory cytokines, antioxidant, and anti-apoptotic indicator, and the activity of Toll-like receptor 4 (TLR4) signaling in lung tissues were evaluated.

RESULTS

Administration of the ADSCs reversed ALI induced by THS, including lung histopathological changes/scores, and BALF total protein concentration. Additionally, ADSCs therapy also significantly down-regulated mRNA expression of pro-inflammatory TNF-α, IL-1β, and IL-6, up-regulated mRNA expression of anti-inflammatory IL-10, anti-apoptotic molecule Bcl-2, and anti-oxidative molecule HO-1 in THS rats. Furthermore, ADSCs suppressed the expression of TLR4 in lung tissue.

CONCLUSION

Our data show that ADSCs administration can exert therapeutic effects on THS-induced ALI in rats and may provide beneficial in preventative strategies for ALI.

Prediction of Survival by IL-6 in a Randomized Placebo-Controlled Trial of Anakinra in COVID-19 Cytokine Storm

(1) Background: Some severe COVID-19 patients develop hyperinflammatory cytokine storm syndrome (CSS). We assessed the efficacy of anakinra added to standard of care (SoC) in hospitalized COVID-19 CSS patients. (2) Methods: In this single-center, randomized, double-blind, placebo-controlled trial (NCT04362111), we recruited adult hospitalized patients with SARS-CoV-2 infection, evidence of pneumonia, new/increasing oxygen requirement, ferritin ≥ 700 ng/mL, and at least three of the following indicators: D-dimer ≥ 500 ng/mL, platelet count < 130,000/mm3, WBC < 3500/mm3 or lymphocyte count < 1000/mm3, AST or ALT > 2X the upper limit of normal (ULN), LDH > 2X ULN, C-reactive protein > 100 mg/L. Patients were randomized (1:1) to SoC plus anakinra (100 mg subcutaneously every 6 h for 10 days) or placebo. All received dexamethasone. The primary outcome was survival and hospital discharge without need for intubation/mechanical ventilation. The data were analyzed according to the modified intention-to-treat approach. (3) Results: Between August 2020 and January 2021, 32 patients were recruited, of which 15 were assigned to the anakinra group, and 17 to the placebo group. Two patients receiving the placebo withdrew within 48 h and were excluded. The mean age was 63 years (SD 10.3), 20 (67%) patients were men, and 20 (67%) were White. At Day 10, one (7%) patient receiving anakinra and two (13%) patients receiving the placebo had died (p = 1.0). At hospital discharge, four (27%) patients receiving anakinra and four (27%) patients receiving the placebo had died. The IL-6 level at enrollment was predictive of death (p < 0.01); anakinra use was associated with decreases in CXCL9 levels. (4) Conclusions: Anakinra added to dexamethasone did not significantly impact the survival of COVID-19 pneumonia patients with CSS. Additional studies are needed to assess patient selection and the efficacy, timing, and duration of anakinra treatment for COVID-19 CSS.

Transitional dendritic cells are distinct from conventional DC2 precursors and mediate proinflammatory antiviral responses

High-dimensional approaches have revealed heterogeneity amongst dendritic cells (DCs), including a population of transitional DCs (tDCs) in mice and humans. However, the origin and relationship of tDCs to other DC subsets has been unclear. Here we show that tDCs are distinct from other well-characterized DCs and conventional DC precursors (pre-cDCs). We demonstrate that tDCs originate from bone marrow progenitors shared with plasmacytoid DCs (pDCs). In the periphery, tDCs contribute to the pool of ESAM+ type 2 DCs (DC2s), and these DC2s have pDC-related developmental features. Different from pre-cDCs, tDCs have less turnover, capture antigen, respond to stimuli and activate antigen-specific naïve T cells, all characteristics of differentiated DCs. Different from pDCs, viral sensing by tDCs results in IL-1β secretion and fatal immune pathology in a murine coronavirus model. Our findings suggest that tDCs are a distinct pDC-related subset with a DC2 differentiation potential and unique proinflammatory function during viral infections.

Advances in attractive therapeutic approach for macrophage activation syndrome in COVID-19

Nowadays, people have relaxed their vigilance against COVID-19 due to its declining infection numbers and attenuated virulence. However, COVID-19 still needs to be concern due to its emerging variants, the relaxation of restrictions as well as breakthrough infections. During the period of the COVID-19 infection, the imbalanced and hyper-responsive immune system plays a critical role in its pathogenesis. Macrophage Activation Syndrome (MAS) is a fatal complication of immune system disease, which is caused by the excessive activation and proliferation of macrophages and cytotoxic T cells (CTL). COVID-19-related hyperinflammation shares common clinical features with the above MAS symptoms, such as hypercytokinemia, hyperferritinemia, and coagulopathy. In MAS, immune exhaustion or defective anti-viral responses leads to the inadequate cytolytic capacity of CTL which contributes to prolonged interaction between CTL, APCs and macrophages. It is possible that the same process also occurred in COVID-19 patients, and further led to a cytokine storm confined to the lungs. It is associated with the poor prognosis of severe patients such as multiple organ failure and even death. The main difference of cytokine storm is that in COVID-19 pneumonia is mainly the specific damage of the lung, while in MAS is easy to develop into a systemic. The attractive therapeutic approach to prevent MAS in COVID-19 mainly includes antiviral, antibiotics, convalescent plasma (CP) therapy and hemadsorption, extensive immunosuppressive agents, and cytokine-targeted therapies. Here, we discuss the role of the therapeutic approaches mentioned above in the two diseases. And we found that the treatment effect of the same therapeutic approach is different.

Pharmacological therapies and drug development targeting SARS-CoV-2 infection

The development of therapies for SARS-CoV-2 infection, based on virus biology and pathology, and of large- and small-scale randomized controlled trials, have brought forward several antiviral and immunomodulatory drugs targeting the disease severity. Casirivimab/Imdevimab monoclonal antibodies and convalescent plasma to prevent virus entry, Remdesivir, Molnupiravir, and Paxlovid nucleotide analogs to prevent viral replication, a variety of repurposed JAK-STAT signaling pathway inhibitors, corticosteroids, and recombinant agonists/antagonists of cytokine and interferons have been found to provide clinical benefits in terms of mortality and hospitalization. However, current treatment options face multiple clinical needs, and therefore, in this review, we provide an update on the challenges of the existing therapeutics and highlight drug development strategies for COVID-19 therapy, based on ongoing clinical trials, meta-analyses, and clinical case reports.

A Review of Potential Therapeutic Strategies for COVID-19

Coronavirus disease 2019 is a rather heterogeneous disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The ongoing pandemic is a global threat with increasing death tolls worldwide. SARS-CoV-2 belongs to lineage B β-CoV, a subgroup of Sarbecovirus. These enveloped, large, positive-sense single-stranded RNA viruses are easily spread among individuals, mainly via the respiratory system and droplets. Although the disease has been gradually controlled in many countries, once social restrictions are relaxed the virus may rebound, leading to a more severe and uncontrollable situation again, as occurred in Shanghai, China, in 2022. The current global health threat calls for the urgent development of effective therapeutic options for the treatment and prevention of SARS-CoV-2 infection. This systematic overview of possible SARS-CoV-2 therapeutic strategies from 2019 to 2022 indicates three potential targets: virus entry, virus replication, and the immune system. The information provided in this review will aid the development of more potent and specific antiviral compounds.

Inflammatory pathways in COVID‐19: Mechanism and therapeutic interventions

The 2019 coronavirus disease (COVID‐19) pandemic has become a global crisis. In the immunopathogenesis of COVID‐19, SARS‐CoV‐2 infection induces an excessive inflammatory response in patients, causing an inflammatory cytokine storm in severe cases. Cytokine storm leads to acute respiratory distress syndrome, pulmonary and other multiorgan failure, which is an important cause of COVID‐19 progression and even death. Among them, activation of inflammatory pathways is a major factor in generating cytokine storms and causing dysregulated immune responses, which is closely related to the severity of viral infection. Therefore, elucidation of the inflammatory signaling pathway of SARS‐CoV‐2 is important in providing otential therapeutic targets and treatment strategies against COVID‐19. Here, we discuss the major inflammatory pathways in the pathogenesis of COVID‐19, including induction, function, and downstream signaling, as well as existing and potential interventions targeting these cytokines or related signaling pathways. We believe that a comprehensive understanding of the regulatory pathways of COVID‐19 immune dysregulation and inflammation will help develop better clinical therapy strategies to effectively control inflammatory diseases, such as COVID‐19.

The SARS-CoV-2 Nucleoprotein Induces Innate Memory in Human Monocytes

The interaction of SARS-CoV-2 with the human immune system is at the basis of the positive or negative outcome of the infection. Monocytes and macrophages, which are major innate immune/inflammatory effector cells, are not directly infected by SARS-CoV-2, however they can react to the virus and mount a strong reaction. Whether this first interaction and reaction may bias innate reactivity to re-challenge, a phenomenon known as innate memory, is currently unexplored and may be part of the long-term sequelae of COVID-19. Here, we have tested the capacity of SARS-CoV-2 and some of its proteins to induce innate memory in human monocytes in vitro. Our preliminary results show that the Spike protein subunits S1 and S2 and the entire heat-inactivated virus have no substantial effect. Conversely, monocytes pre-exposed to the nucleocapsid N protein react to subsequent viral or bacterial challenges with an increased production of anti-inflammatory IL-1Ra, a response profile suggesting a milder response to new infections.

Immunouniverse of SARS-CoV-2

SARS-CoV-2 virus has become a global health problem that has caused millions of deaths worldwide. The infection can present with multiple clinical features ranging from asymptomatic or mildly symptomatic patients to patients with severe or critical illness that can even lead to death. Although the immune system plays an important role in pathogen control, SARS-CoV-2 can drive dysregulation of this response and trigger severe immunopathology. Exploring the mechanisms of the immune response involved in host defense against SARS-CoV-2 allows us to understand its immunopathogenesis and possibly detect features that can be used as potential therapies to eliminate the virus. The main objective of this review on SARS-CoV-2 is to highlight the interaction between the virus and the immune response. We explore the function and action of the immune system, the expression of molecules at the site of infection that cause hyperinflammation and hypercoagulation disorders, the factors leading to the development of pneumonia and subsequent severe acute respiratory distress syndrome which is the leading cause of death in patients with COVID-19.

Immune mechanisms in cancer patients that lead to poor outcomes of SARS-CoV-2 infection

Patients with cancers have been severely affected by the COVID-19 pandemic. This is highlighted by the adverse outcomes in cancer patients with COVID-19 as well as by the impact of the COVID-19 pandemic on cancer care. Patients with cancer constitute a heterogeneous population that exhibits distinct mechanisms of immune dysfunction, associated with distinct systemic features of hot (T-cell-inflamed/infiltrated) and cold (Non-T-cell-inflamed and/or infiltrated) tumors. The former show hyper immune activated cells and a highly inflammatory environment while, contrastingly, the latter show the profile of a senescent and/or quiescent immune system. Thus, the evolution of SARS-CoV-2 infection in different types of cancers can show distinct trajectories which could lead to a variety of clinical and pathophysiological outcomes. The altered immunological environment including cytokines that characterizes hot and cold tumors will lead to different mechanisms of immune dysfunction, which will result in downstream effects on the course of SARS-CoV-2 infection. This review will focus on defining the known contributions of soluble pro- and anti-inflammatory mediators on immune function including altered T-cells and B-cells responses and as well on how these factors modulate the expression of SARS-CoV-2 receptor ACE2, TMPRSS2 expression, and lymph node fibrosis in cancer patients. We will propose immune mechanisms that underlie the distinct courses of SARS-CoV-2 infection in cancer patients and impact on the success of immune based therapies that have significantly improved cancer outcomes. Better understanding of the immune mechanisms prevalent in cancer patients that are associated to the outcomes of SARS-CoV-2 infection will help to identify the high-risk cancer patients and develop immune-based approaches to prevent significant adverse outcomes by targeting these pathways.

Identifying potential novel insights for COVID-19 pathogenesis and therapeutics using an integrated bioinformatics analysis of host transcriptome

The molecular mechanisms underlying the pathogenesis of COVID-19 have not been fully discovered. This study aims to decipher potentially hidden parts of the pathogenesis of COVID-19, potential novel drug targets, and identify potential drug candidates. Two gene expression profiles were analyzed, and overlapping differentially expressed genes (DEGs) were selected for which top enriched transcription factors and kinases were identified, and pathway analysis was performed. Protein-protein interaction (PPI) of DEGs was constructed, hub genes were identified, and module analysis was also performed. DGIdb database was used to identify drugs for the potential targets (hub genes and the most enriched transcription factors and kinases for DEGs). A drug-potential target network was constructed, and drugs were ranked according to the degree. L1000FDW was used to identify drugs that can reverse transcriptional profiles of COVID-19. We identified drugs currently in clinical trials, others predicted by different methods, and novel potential drug candidates Entrectinib, Omeprazole, and Exemestane for combating COVID-19. Besides the well-known pathogenic pathways, it was found that axon guidance is a potential pathogenic pathway. Sema7A, which may exacerbate hypercytokinemia, is considered a potential novel drug target. Another potential novel pathway is related to TINF2 overexpression, which may induce potential telomere dysfunction and damage DNA that may exacerbate lung fibrosis. This study identified new potential insights regarding COVID-19 pathogenesis and treatment, which might help us improve our understanding of the mechanisms of COVID-19.

Immunomonitoring of Monocyte and Neutrophil Function in Critically Ill Patients: From Sepsis and/or Trauma to COVID-19

Immune cells and mediators play a crucial role in the critical care setting but are understudied. This review explores the concept of sepsis and/or injury-induced immunosuppression and immuno-inflammatory response in COVID-19 and reiterates the need for more accurate functional immunomonitoring of monocyte and neutrophil function in these critically ill patients. in addition, the feasibility of circulating and cell-surface immune biomarkers as predictors of infection and/or outcome in critically ill patients is explored. It is clear that, for critically ill, one size does not fit all and that immune phenotyping of critically ill patients may allow the development of a more personalized approach with tailored immunotherapy for the specific patient. In addition, at this point in time, caution is advised regarding the quality of evidence of some COVID-19 studies in the literature.

COVID-19 and Rheumatoid Arthritis Crosstalk: Emerging Association, Therapeutic Options and Challenges

Hyperactivation of immune responses resulting in excessive release of pro-inflammatory mediators in alveoli/lung structures is the principal pathological feature of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The cytokine hyperactivation in COVID-19 appears to be similar to those seen in rheumatoid arthritis (RA), an autoimmune disease. Emerging evidence conferred the severity and risk of COVID-19 to RA patients. Amid the evidence of musculoskeletal manifestations involving immune-inflammation-dependent mechanisms and cases of arthralgia and/or myalgia in COVID-19, crosstalk between COVID-19 and RA is often debated. The present article sheds light on the pathological crosstalk between COVID-19 and RA, the risk of RA patients in acquiring SARS-CoV-2 infection, and the aspects of SARS-CoV-2 infection in RA development. We also conferred whether RA can exacerbate COVID-19 outcomes based on available clinical readouts. The mechanistic overlapping in immune-inflammatory features in both COVID-19 and RA was discussed. We showed the emerging links of angiotensin-converting enzyme (ACE)-dependent and macrophage-mediated pathways in both diseases. Moreover, a detailed review of immediate challenges and key recommendations for anti-rheumatic drugs in the COVID-19 setting was presented for better clinical monitoring and management of RA patients. Taken together, the present article summarizes available knowledge on the emerging COVID-19 and RA crosstalk and their mechanistic overlaps, challenges, and therapeutic options.