Prospective Variation of Cytokine Trends during COVID-19: A Progressive Approach from Disease Onset until Outcome.

COVID-19 is characterized by pronounced hypercytokinemia. The cytokine switch, marked by an imbalance between pro-inflammatory and anti-inflammatory cytokines, emerged as a focal point of investigation throughout the COVID-19 pandemic. However, the kinetics and temporal dynamics of cytokine release remain contradictory, making the development of new therapeutics difficult, especially in severe cases. This study collected serum samples from SARS-CoV-2 infected patients at 72 h intervals and monitored them for various cytokines at each timepoint until hospital discharge or death. Cytokine levels were analyzed based on time since symptom onset and patient outcomes. All cytokines studied prospectively were strong predictors of mortality, particularly IL-4 (AUC = 0.98) and IL-1ß (AUC = 0.96). First-timepoint evaluations showed elevated cytokine levels in the mortality group (p < 0.001). Interestingly, IFN-γ levels decreased over time in the death group but increased in the survival group. Patients who died exhibited sustained levels of IL-1ß and IL-4 and increased IL-6 levels over time. These findings suggest cytokine elevation is crucial in predicting COVID-19 mortality. The dynamic interplay between IFN-γ and IL-4 highlights the balance between Th1/Th2 immune responses and underscores IFN-γ as a powerful indicator of immune dysregulation throughout the infection.

Avanços no entendimento da patogenia da Covid-19: uma revisão / Advances in understanding Covid-19 pathogenesis: a review / Avances en la comprensión de la patogenia de la Covid-19: una revisión

Introdução: O SARS-CoV-2, causador da pandemia por Doença por Coronavirus 2019 (COVID-19) gerou desafios à saúde pública, principalmente pelo conhecimento escasso de sua patogênese, e de estratégias terapêuticas e preventivas eficazes. Diversas lacunas de conhecimento sobre a doença envolvem a contribuição de fatores de risco, as doenças concomitantes, os fatores genéticos e imunogenéticos, no direcionamento da resposta imune, bem como a hiperinflamação, a imunidade antiviral e os alelos dos antígenos leucocitários humanos (HLAs) dos pacientes, que estão relacionados ao desfecho da doença. Objetivo: Esta revisão integrativa objetivou aprofundar os conhecimentos sobre os mecanismos de imunidade relacionada aos fatores de risco, da hiperinflamação e da tempestade de citocinas decorrente da infecção por SARS-CoV-2, bem como os avanços de associação dos HLAs nos agravos da doença. Metodologia: A revisão integrativa foi realizada utilizando os descritores nas bases de dados PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, Portal periódicos CAPES e Open Journal System, sem limites de janela cronológica. Resultados: Os efeitos da pandemia e os esforços na busca do conhecimento sobre a patogênese da COVID-19 resultaram em avanço no combate da doença. Conseguiu-se relacionar fatores de risco como obesidade, hipertensão, diabetes, doenças renais crônicas, idade, gênero, e outras condições predisponentes ao agravo da doença. Sob o aspecto da patogênese, também houveram progressos no entendimento dos mecanismos celulares e humorais em resposta à doença, bem como conseguiu vincular a resposta da hiperinflamação e o perfil dos HLAs dos pacientes à evolução da doença ao óbito ou à convalescência. Conclusão: Os esforços científicos conjuntos e os avanços na compreensão dos mecanismos da doença conseguiram estabelecer estratégias de combate a COVID-19, resultando no fim da pandemia, porém ainda há avanços que devem ser alcançados para o combate das sequelas dos pacientes convalescentes e para minimização da COVID longa e seus prejuízos.

Introduction: SARS-CoV-2, which causes the Coronavirus Disease 2019 (COVID-19) pandemic, has generated challenges to public health, mainly due to the limited knowledge of its pathogenesis and effective therapeutic and preventive strategies. Several gaps in knowledge about the disease involve the contribution of risk factors, concomitant diseases, genetic and immunogenetic factors, in directing the immune response, as well as hyperinflammation, antiviral immunity and human leukocyte antigen (HLAs) alleles of patients, which are related to the outcome of the disease. Aim: This integrative review aimed to deepen knowledge about the mechanisms of immunity related to risk factors, hyperinflammation and the cytokine storm resulting from SARS-CoV-2 infection, as well as advances in the association of HLAs in diseases. Methodology: The integrative review was carried out using the descriptors in the databases PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, CAPES periodical portal and Open Journal System, without chronological window limits. Results: The effects of the pandemic and efforts to seek knowledge about the pathogenesis of COVID-19 resulted in progress in combating the disease. It was possible to relate risk factors such as obesity, hypertension, diabetes, chronic kidney disease, age, gender, and other conditions predisposing to the worsening of the disease. From the aspect of pathogenesis, progress has also been made in understanding the cellular and humoral mechanisms in response to the disease, as well as linking the hyperinflammation response and the patients' HLA profile to the progression of the disease to death or convalescence. Conclusion: Joint scientific efforts and advances in understanding the mechanisms of the disease managed to establish strategies to combat COVID-19, resulting in the end of the pandemic, but there are still advances that must be achieved to combat the sequelae of convalescent patients and to minimize of long COVID and its losses.

Introducción: El SARS-CoV-2, causante de la pandemia de la Enfermedad del Coronavirus 2019 (COVID-19), ha generado desafíos a la salud pública, principalmente por el limitado conocimiento de su patogénesis y estrategias terapéuticas y preventivas efectivas. Varios vacíos en el conocimiento sobre la enfermedad involucran la contribución de factores de riesgo, enfermedades concomitantes, factores genéticos e inmunogenéticos, en la dirección de la respuesta inmune, así como la hiperinflamación, la inmunidad antiviral y los alelos del antígeno leucocitario humano (HLA) de los pacientes, que están relacionados con el resultado de la enfermedad. Objetivo: Esta revisión integradora tuvo como objetivo profundizar el conocimiento sobre los mecanismos de inmunidad relacionados con los factores de riesgo, la hiperinflamación y la tormenta de citocinas resultante de la infección por SARS-CoV-2, así como los avances en la asociación de los HLA en las complicaciones de la enfermedad. Metodología: La revisión integradora se realizó utilizando los descriptores de las bases de datos PubMed, SCIELO, CINAHL, SCOPUS, Web of Science, MedNar, portal periódico CAPES y Open Journal System, sin límites de ventana cronológica. Resultados: Los efectos de la pandemia y los esfuerzos por buscar conocimiento sobre la patogénesis de la COVID-19 resultaron en avances en el combate de la enfermedad. Se logró relacionar factores de riesgo como obesidad, hipertensión, diabetes, enfermedad renal crónica, edad, sexo y otras condiciones que predisponen al agravamiento de la enfermedad. Desde el punto de vista de la patogénesis, también se ha avanzado en la comprensión de los mecanismos celulares y humorales de respuesta a la enfermedad, así como en la vinculación de la respuesta de hiperinflamación y el perfil HLA de los pacientes con la progresión de la enfermedad hasta la muerte o la convalecencia. Conclusión: Los esfuerzos científicos conjuntos y los avances en la comprensión de los mecanismos de la enfermedad lograron establecer estrategias para combatir el COVID-19, teniendo como resultado el fin de la pandemia, pero aún quedan avances que se deben lograr para combatir las secuelas de los pacientes convalecientes y para Minimizar el COVID prolongado y sus pérdidas.

Purinergic signaling in the battlefield of viral infections.

Purinergic signaling has been associated with immune defenses against pathogens such as bacteria, protozoa, fungi, and viruses, acting as a sentinel system that signals to the cells when a threat is present. This review focuses on the roles of purinergic signaling and its therapeutic potential for viral infections. In this context, the purinergic system may play potent antiviral roles by boosting interferon signaling. In other cases, though, it can contribute to a hyperinflammatory response and disease severity, resulting in poor outcomes, such as during flu and potentially COVID-19. Lastly, a third situation may occur since viruses are obligatory intracellular parasites that hijack the host cell machinery for their infection and replication. Viruses such as HIV-1 use the purinergic system to favor their infection and persistence within the host cell. Therefore, understanding the particular nuances of purinergic signaling in each viral infection may contribute to designing proper therapeutic strategies to treat viral diseases.

Highlights of clinical and laboratory parameters among severe COVID-19 patients treated with tocilizumab: a retrospective observational study

ABSTRACT BACKGROUND: Coronavirus disease 2019 (COVID-19) can cause cytokine release syndrome (CRS), which leads to high mortality rates. Tocilizumab suppresses CRS by blocking the signal transduction of interleukin-6 (IL-6). OBJECTIVE: To evaluate the clinical and laboratory parameters associated with mortality among patients receiving tocilizumab treatment. DESIGN AND SETTING: Retrospective observational study conducted in the chest disease departments of two different training and research hospitals in the center of Ankara, Turkey. METHODS: Patients who were hospitalized and treated with tocilizumab in September 2020 were retrospectively analyzed. Their laboratory parameters and clinical characteristics were obtained from the hospital information system database. Comparative analyses were performed between the patients who died and the ones who survived. RESULTS: A total of 58 patients who received tocilizumab treatment were included in this study, among whom 35 (60.3%) died. There was no difference between the mortality and survival groups in terms of white blood cell (WBC), neutrophil, lymphocyte, ferritin or C-reactive protein (CRP) levels detected on admission. WBC, lymphocyte, neutrophil and CRP levels measured on the third and fifth days after tocilizumab administration were found to be significantly lower in the survival group (P < 0.05). In multiple logistic regression analysis, age and oxygen saturation were determined to be independent risk factors for mortality. CONCLUSION: Persistently high WBC, CRP and neutrophil levels and low lymphocyte levels could be considered to be valuable indicators of mortality among COVID-19 patients treated with tocilizumab. Age and low oxygen saturation are independent risk factors for mortality among patients receiving tocilizumab treatment.

Efferocytosis of SARS-CoV-2-infected dying cells impairs macrophage anti-inflammatory functions and clearance of apoptotic cells.

COVID-19 is a disease of dysfunctional immune responses, but the mechanisms triggering immunopathogenesis are not established. The functional plasticity of macrophages allows this cell type to promote pathogen elimination and inflammation or suppress inflammation and promote tissue remodeling and injury repair. During an infection, the clearance of dead and dying cells, a process named efferocytosis, can modulate the interplay between these contrasting functions. Here, we show that engulfment of SARS-CoV-2-infected apoptotic cells exacerbates inflammatory cytokine production, inhibits the expression of efferocytic receptors, and impairs continual efferocytosis by macrophages. We also provide evidence supporting that lung monocytes and macrophages from severe COVID-19 patients have compromised efferocytic capacity. Our findings reveal that dysfunctional efferocytosis of SARS-CoV-2-infected cell corpses suppresses macrophage anti-inflammation and efficient tissue repair programs and provides mechanistic insights for the excessive production of pro-inflammatory cytokines and accumulation of tissue damage associated with COVID-19 immunopathogenesis.

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.

Molecular mechanisms implicated in SARS-CoV-2 liver tropism.

The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Hepatic involvement is common in SARS-CoV-2-infected individuals. It is currently accepted that the direct and indirect hepatic effects of SARS-CoV-2 infection play a significant role in COVID-19. In individuals with pre-existing infectious and non-infectious liver disease, who are at a remarkably higher risk of developing severe COVID-19 and death, this pathology is most medically relevant. This review emphasizes the current pathways regarded as contributing to the gastrointestinal and hepatic ailments linked to COVID-19-infected patients due to an imbalanced interaction among the liver, systemic inflammation, disrupted coagulation, and the lung.

El tratamiento con Jusvinza disminuye la hiperinflamación y la hipercoagulación en pacientes críticos con la COVID-19

RESUMEN Introducción: La infección con el SARS-CoV-2 induce un estado protrombótico en los pacientes, atribuible a la combinación de la respuesta hiperinflamatoria y la hipoxia. En Cuba, se usa el fármaco Jusvinza, basado en un péptido inmunomodulador, para el tratamiento de los pacientes con la COVID-19, que presenten signos y síntomas de hiperinflamación. Objetivos: Describir la evolución clínica y las variaciones de biomarcadores asociados con la inflamación y la coagulación, en un grupo de pacientes críticos con la COVID-19, tratados con Jusvinza, en comparación con un grupo de pacientes que no recibieron tratamiento con este péptido. Métodos: Se incluyeron 40 pacientes críticos con la COVID-19; se dividieron en 2 grupos: 20 pacientes tratados con Jusvinza y 20 no fueron tratados con dicho péptido (grupo control). Las características demográficas, comorbilidades, signos vitales, parámetros respiratorios, biomarcadores de la inflamación y de la coagulación se obtuvieron a partir de las historias clínicas de cada paciente. Resultados: El tratamiento con Jusvinza indujo una mejoría clínica en los pacientes, asociada con la disminución de varios biomarcadores de la inflamación y la coagulación. La sobrevida de los pacientes tratados con Jusvinza fue significativamente superior a la sobrevida de los pacientes no tratados con este péptido. Conclusiones: Jusvinza es capaz de controlar la hiperinflamación y la hipercoagulación en pacientes críticos con la COVID-19.

ABSTRACT Introduction: Infection with SARS-CoV-2 induces a prothrombotic state in patients, by the combination of hyperinflammatory response and hypoxia. In Cuba, the drug called Jusvinza, based on an immunomodulatory peptide, is used for the treatment of patients with COVID-19, who present signs and symptoms of hyperinflammation. Objectives: To describe the clinical course and behavior of various biomarkers associated with the inflammation and coagulation, in a group of critically ill patients with COVID-19 treated with Jusvinza, compared to a group of patients who did not receive treatment with this peptide. Methods: 40 critically ill patients with COVID-19 were included. The patients were divided into 2 groups: 20 patients were treated with Jusvinza and 20 were not treated with this peptide (control group). Demographic characteristics, comorbidities, vital signs, respiratory parameters and inflammation and coagulation biomarkers were obtained from the medical records of each patient. Results: Treatment with Jusvinza induced a clinical improvement in the patients, associated with the decrease of several inflammation and coagulation biomarkers. Patients treated with Jusvinza had a significantly higher survival than patients not treated with this peptide. Conclusions: Jusvinza is able to control hyperinflammation and hypercoagulation in critical ill patients with COVID-19.

COVID-19 in the Context of Inborn Errors of Immunity: a Case Series of 31 Patients from Mexico.

INTRODUCTION: Patients with inborn errors of immunity (IEI) have a compromised or inappropriate immune response. Although they might be considered a high-risk group for severe SARS-CoV-2 infection, the reported impact of COVID-19 in these patients has been reassuring, while the differential susceptibility of distinct types of IEI remains unclear. OBJECTIVE: We aimed to describe the findings and outcomes of our known patients with IEI who were diagnosed with COVID-19. METHODS: In a retrospective study from March 2020 to February 2021, four centers in Mexico collected clinical, laboratory, and genetic data from pediatric and adult patients with known diagnoses of IEI who presented with COVID-19, based on compatible symptoms and positive SARS-CoV-2 testing or known household exposure. RESULTS: We report 31 patients with known IEI from Mexico who presented with SARS-CoV-2 infection. Seventy-four percent were male, 52% were pediatric, and 81% survived. Their ages ranged from 5 months to 56 years, with a median of 17 years. Sixty-five percent had predominant antibody deficiencies, 48% were hospitalized, and 26% required ICU. Pediatric patients had a higher hospital admission rate than adults. Inpatient mortality was 40%, and ICU mortality rate was 63%. Forty-eight percent developed pneumonia, while 36% had evidence of hyperinflammation (4 adults and 7 children). Predominant laboratory features were lymphopenia and thrombocytopenia, seen in 70 and 44% of patients, respectively. The serum D-dimer median value was 2.6 (0.5-20.6) µg/mL, and the median highest ferritin value was 1015 (32-10,303) ng/mL. Intravenous immunoglobulin was used in 80% of patients. Other treatments included macrolides (39%) and corticosteroids (29%). Six patients died from secondary infection or uncontrolled systemic inflammation. DISCUSSION: Although impaired immunity due to IEI may be a predisposing factor for severe COVID-19, most of our patients with IEI who acquired the SARS-CoV-2 infection developed a well-tolerated infection and survived, as have more than 80% of worldwide reported patients to date. An impaired immune or inflammatory response may be a predisposing factor for some and a protective factor for others. A systematic review of the literature could help identify those patients at risk of severe disease and complications. Healthcare-associated infections should be aggressively prevented.

Hyperinflammation and airway surface liquid dehydration in cystic fibrosis: purinergic system as therapeutic target.

OBJECTIVE AND DESIGN: The exacerbate inflammatory response contributes to the progressive loss of lung function in cystic fibrosis (CF), a genetic disease that affects the osmotic balance of mucus and mucociliary clearance, resulting in a microenvironment that favors infection and inflammation. The purinergic system, an extracellular signaling pathway characterized by nucleotides, enzymes and receptors, may have a protective role in the disease, through its action in airway surface liquid (ASL) and anti-inflammatory response. MATERIALS AND METHODS: To make up this review, studies covering topics of CF, inflammation, ASL and purinergic system were selected from the main medical databases, such as Pubmed and ScienceDirect. CONCLUSION: We propose several ways to modulate the purinergic system as a potential therapy for CF, like inhibition of P2X7, activation of P2Y2, A2A and A2B receptors and blocking of adenosine deaminase. Among them, we postulate that the most suitable strategy is to block the action of adenosine deaminase, which culminates in the increase of Ado levels that presents anti-inflammatory actions and improves mucociliary clearance. Furthermore, it is possible to maintain the physiological levels of ATP to control the hydration of ASL. These therapies could correct the main mechanisms that contribute to the progression of CF.

CIGB-258, a peptide derived from human heat-shock protein 60, decreases hyperinflammation in COVID-19 patients.

Hyperinflammation distinguishes COVID-19 patients who develop a slight disease or none, from those progressing to severe and critical conditions. CIGB-258 is a therapeutic option for the latter group of patients. This drug is an altered peptide ligand (APL) derived from the cellular stress protein 60 (HSP60). In preclinical models, this peptide developed anti-inflammatory effects and increased regulatory T cell (Treg) activity. Results from a phase I clinical trial with rheumatoid arthritis (RA) patients indicated that CIGB-258 was safe and reduced inflammation. The aim of this study was to examine specific biomarkers associated with hyperinflammation, some cytokines linked to the cytokine storm granzyme B and perforin in a cohort of COVID-19 patients treated with this peptide. All critically ill patients were under invasive mechanical ventilation and received the intravenous administration of 1 or 2 mg of CIGB-258 every 12 h. Seriously ill patients were treated with oxygen therapy receiving 1 mg of CIGB-258 every 12 h and all patients recovered from their severe condition. Biomarker levels associated with hyperinflammation, such as interleukin (IL)-6, IL-10, tumor necrosis factor (TNF-α), granzyme B, and perforin, significantly decreased during treatment. Furthermore, we studied the ability of CIGB-258 to induce Tregs in COVID-19 patients and found that Tregs were induced in all patients studied. Altogether, these results support the therapeutic potential of CIGB-258 for diseases associated with hyperinflammation. Clinical trial registry: RPCEC00000313.

Melatonin, Zinc, and Vitamin C: Potential Adjuvant Treatment for COVID-19 Patients.

The use of nutraceutical approaches may regulate the immune system, performing a potential strategy to contain the worst outcomes of COVID-19. We reviewed the current evidence surrounding nutritional/nutraceutical approaches for the therapy in patients with COVID-19. We searched the PubMed database to report randomized controlled trials (RCTs) and observational research that used melatonin, zinc, or vitamin C supplementation as an intervention for COVID-19 treatment. To date, we found only three concluded studies that assessed zinc supplementation and melatonin therapy in patients with COVID-19, but with inconclusive data, relatively small sample size, and early termination of the trial. On the other hand, vitamin C therapy appears to reduce hyperinflammation and improve the oxygen support status of patients with COVID-19. However, a large part of this research involves pilot trials, and there are still conflicting data regarding mortality rate, mechanical ventilation, and duration of symptoms of patients with COVID-19. Melatonin, zinc, and vitamin C supplementation should be investigated further on the nutritional status-immune response, and data from ongoing trials are needed to understand these molecules as a therapy strategy in patients COVID-19.

Péptido inmunomodulador CIGB-258 para el tratamiento de pacientes graves y críticos con la COVID-19 / An immunomodulatory peptide CIGB-258 for the treatment of critical and severe COVID-19 patients

Introducción: El CIGB-258 es un péptido inmunomodulador con propiedades antiinflamatorias. Objetivos: Establecer la frecuencia de dosis y el tiempo de tratamiento con el péptido CIGB-258, para pacientes críticos con COVID-19. Además, definir los criterios de uso y el esquema terapéutico del péptido, para pacientes graves con COVID-19. Métodos: Se incluyeron 9 pacientes críticos y 3 pacientes graves. Las evaluaciones clínicas, radiológicas y de laboratorio se registraron de acuerdo al protocolo establecido. Se obtuvieron muestras de suero antes y después del tratamiento con la CIGB-258, para la determinación de los biomarcadores de la inflamación. Resultados: Se estableció el protocolo de actuación con el péptido CIGB-258, el cual consiste en la administración intravenosa de 1 mg del péptido cada 12 horas a los pacientes críticos. La dosis debe aumentarse a 2 mg cada 12 horas, para los pacientes que no muestren mejoría clínica y radiológica en 24 horas. Después de la extubación, los pacientes deben recibir 1 mg de CIGB-258 al día, durante otros tres días. Los pacientes graves deben recibir 1 mg de CIGB-258 cada 12 horas, hasta que resuelvan su condición clínica. Conclusiones: CIGB-258 mostró un buen perfil de seguridad. El protocolo de actuación establecido contribuyó a que todos los pacientes críticos se recuperaran de la dificultad respiratoria y fueran extubados. Los pacientes graves mejoraron considerablemente. Los niveles de los biomarcadores asociados con hiperinflamación y las citocinas disminuyeron significativamente durante el tratamiento(AU)

Introduction: CIGB-258 is an immunomodulatory peptide with anti-inflammatory properties. Objectives: To establish the therapeutic schedule with CIGB-258 peptide for COVID-19 critically ill patients. In addition, to define the criteria for use and schedule of this peptide for COVID-19 seriously ill patients. Methods: 9 critically ill patients and 3 seriously ill patients were included in this study. Clinical, radiological and laboratory evaluations were recorded according to the established protocol. Serum samples were obtained before and after treatment with CIGB-258, for the determination of the inflammation biomarkers. Results: The therapeutic protocol was established with the CIGB-258 peptide, which consists of intravenous administration of 1 mg of peptide every 12 hours for critically ill patients. The dose should be increased to 2 mg every 12 hours, for patients who do not show clinical and radiological improvement in 24 hours. After extubation, patients should receive 1 mg of CIGB-258 daily, for another three days. Seriously ill patients should receive 1 mg of CIGB-258 every 12 hours, until their clinical condition resolves. Conclusions: CIGB-258 showed an excellent safety profile. The established therapeutic protocol contributed to all critically ill patients recovering from respiratory distress and being extubated. Seriously ill patients improved considerably. The levels of the biomarkers associated with hyperinflammation and cytokines decreased significantly during treatment(AU)

COVID-19: Rational discovery of the therapeutic potential of Melatonin as a SARS-CoV-2 main Protease Inhibitor.

The SARS-CoV-2 spread quickly across the globe. The World Health Organization (WHO) on March 11 declared COVID-19 a pandemic. The mortality rate, hospital disorders and incalculable economic and social damages, besides the unproven efficacy of the treatments evaluated against COVID-19, raised the need for immediate control of this disease. Therefore, the current study employed in silico tools to rationally identify new possible SARS-CoV-2 main protease (Mpro) inhibitors. That is an enzyme conserved among the coronavirus species; hence, the identification of an Mpro inhibitor is to make it a broad-spectrum drug. Molecular docking studies described the binding sites and the interaction energies of 74 Mpro-ligand complexes deposited in the Protein Data Bank (PDB). A structural similarity screening was carried out in order to identify possible Mpro ligands that show additional pharmacological properties against COVID-19. We identified 59 hit compounds and among them, melatonin stood out due to its prominent immunomodulatory and anti-inflammatory activities; it can reduce oxidative stress, defence cell mobility and efficiently combat the cytokine storm and sepsis. In addition, melatonin is an inhibitor of calmodulin, an essential intracellular component to maintain angiotensin-converting enzyme 2 (ACE-2) on the cell surface. Interestingly, one of the most promising hits in our docking study was melatonin. It revealed better interaction energy with Mpro compared to ligands in complexes from PDB. Consequently, melatonin can have response potential in early stages for its possible effects on ACE-2 and Mpro, although it is also promising in more severe stages of the disease for its action against hyper-inflammation. These results definitely do not confirm antiviral activity, but can rather be used as a basis for further preclinical and clinical trials.

Calcineurin inhibitors revisited: A new paradigm for COVID-19?

Abstract The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can cause mild, moderate or severe disease (COVID-19). In severe disease, there is hyperinflammation causing severe symptoms. Severe COVID-19 is an immunological phenomenon, rather than a direct viral damage disease. Therapies for COVID-19 are all investigational therapies. In case of severe disease, treatment with a calcineurin inhibitor could be promising. In this article we explain the mechanisms of calcineurin inhibitor treatment for COVID-19, based on experiences seen in solid organ transplant recipients who suffered from COVID-19.

Calcineurin inhibitors revisited: A new paradigm for COVID-19?

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) can cause mild, moderate or severe disease (COVID-19). In severe disease, there is hyperinflammation causing severe symptoms. Severe COVID-19 is an immunological phenomenon, rather than a direct viral damage disease. Therapies for COVID-19 are all investigational therapies. In case of severe disease, treatment with a calcineurin inhibitor could be promising. In this article we explain the mechanisms of calcineurin inhibitor treatment for COVID-19, based on experiences seen in solid organ transplant recipients who suffered from COVID-19.

Recovery of COVID-19 acute respiratory distress syndrome with tocilizumab: successful outcome in two critically ill patients.

Background: Severe pneumonia and acute respiratory distress syndrome (ARDS) due to COVID-19 is a challenge for nowadays medical practice. Although there is no clarity in the principal mechanism of lung damage and ARDS development, it has been suggested that one of the main reasons of this pathology is the hyperactivation of the immune system, better known as cytokine storm syndrome. Tocilizumab has been proposed to treat COVID-19 severe cases associated to ARDS. Results & methodology: Here we present two successful cases of tocilizumab administration in two COVID-19 patients with prior administration of antiviral therapy (hydroxychloroquine, azithromycin, lopinavir and ritonavir) with adequate response and resolution of ARDS, septic shock and severe pneumonia within the first 72 h. Discussion & conclusion: This case supports the usage of tocilizumab as an effective therapy in COVID-19 associated cytokine storm syndrome. Further studies should be done in order to assess its effectiveness and security.

Imbalance of NET and Alpha-1-Antitrypsin in Tuberculosis Patients Is Related With Hyper Inflammation and Severe Lung Tissue Damage.

Background: Pulmonary tuberculosis (PTB) can lead to lung tissue damage (LTD) and compromise the pulmonary capacity of TB patients that evolve to severe PTB. The molecular mechanisms involved in LTD during anti-tuberculous treatment (ATT) remain poorly understood. Methods and findings: We evaluated the role of neutrophil extracellular trap (NET) and the occurrence of LTD through chest radiographic images, the microbial load in sputum, and inflammatory serum profile (IL-12p40/p70, IL-8, IL-17A, IL-23, VEGF-A, MMP-1, and -8, galectin-3, citrunillated histone H3-cit-H3, alpha-1-antitrypsin-α1AT, C-reactive protein-CRP and albumin) in a cohort of 82 PTB patients before and after 60 days of ATT. Using univariate analysis, LTD was associated with neutrophilia and increase of several inflammatory proteins involved in the neutrophil-mediated response, being cit-H3 the more related to the event. In the multivariate analysis, neutrophilia and cit-H3 appear as directly related to LTD. The analysis of the ROC curve at day 60 presented AUC of 0.97 (95.0% CI 0.95-1). Interestingly, at day 0 of ATT, these biomarkers demonstrated fine relation with LTD showing an AUC 0.92 (95.0% CI 0.86-0.99). Despite of that, the same molecules have no impact in culture conversion during ATT. Conclusions: Our data revealed that NETs may play a key role in the pathway responsible for non-specific inflammation and tissue destruction in PTB. High level of cit-H3 and low level of α1AT was observed in the serum of severe TB patients, suggesting a breakdown in the intrinsic control of NET-driven tissue damage. These data show a new insight to knowledge TB immunopathogenesis, the role of neutrophil and NET pathway. Likewise, we identified possible biomarkers to screening of PTB patients eligible to adjuvants therapies, as anti-inflammatories and alpha-1-antitrypsin.