key: cord-1047950-68spkk3y authors: Luo, Wen; Zhang, Jia‐Wen; Zhang, Wei; Lin, Yuan‐Long; Wang, Qi title: Circulating Levels of IL‐2, IL‐4, TNF‐α, IFN‐γ and C reactive protein Are Not Associated with Severity of COVID‐19 Symptoms date: 2020-06-10 journal: J Med Virol DOI: 10.1002/jmv.26156 sha: 2d195fd7e1a7766d11f9d7373a98f57d9a7d0b2d doc_id: 1047950 cord_uid: 68spkk3y As of May 5, 2020, the total number of coronavirus disease 2019 (COVID‐19) cases had reached over 3.5 million worldwide. The outbreak of COVID‐19 has been officially declared as a pandemic by the World Health Organization because of global spread and severity. Accumulating evidence has been showed that patients with severe COVID‐19 have a cytokine storm syndrome. This article is protected by copyright. All rights reserved. associated with circulating levels of IL-2, IL-4, TNF-α, IFN-γ and C reactive protein. Antiinflammatory agents were believed to combat against severe COVID-19 patients, we suggest the anti-inflammatory drugs should be used very carefully based on our observation. At least, each patients should be tested circulating levels of inflammatory cytokines before launching anti-inflammatory treatment. In summary, our study will benefit to guidance of COVID-19 clinical treatment strategy. The pandemic outbreak of coronavirus disease 2019 (COVID-19) is sharply spreading all over the world. The severity of a viral disease usually is positive association with immunemediated inflammatory responses. The aggressive and persistent inflammatory response leads to high risk of multiorgan failure and death (1) . Antiviral drugs are a generally effective approach to treat severe viral infection. However, resistant viruses may arise upon administration of the antiviral drugs (2) . Thus, anti-inflammation agents are critical for releasing severity of disease but not for viral clearance. The overproduction inflammatory cytokines results in cytokine storm, cytokine storm indicates excessive release of proinflammatory cytokines including C reactive protein and pro-inflammatory cytokines (TNF-α, IL-8, et al) (3) . The extraordinary body of evidences suggest that severe COVID-19 patients have cytokine storm (4) (5) (6) (7) (8) . The high levels of cytokines manifest the destructive process by leading to pneumonia, vascular endotheliitis, coagulopathy and other lifethreatening respiratory symptoms in COVID-19 patients (9, 10) . Moreover, coagulopathy was recently showed to be associated with COVID-19 severity in Caucasian patients (11) . However, the relationship between cytokines storm and COVID-19 pathology still keeps elusive. Here, we analyzed the cytokines level in COVID-19 patients admitted to the intensive care unit (ICU) with hypoxemic respiratory failure. We found cytokine storm of IL-2, IL-4, TNF-α, IFN-γ and C reactive protein is absent in these 25 patients. Our observation suggest anti-inflammation agents can not apply to each patient although they are in ICU. We highlight that circulating levels of inflammatory cytokines should be tested before any antiinflammatory treatment, in case inhibition of essential but not excessive cytokines for priming immune responses against SARS-CoV-2. The non-appropriate anti-inflammatory treatment might be harmful in the context of the COVID-19 pandemic. A total of 25 patients from 39 to 85 years old were confirmed to be SARS-CoV-2 positive in nasopharyngeal swabs. The clinical characteristics and chest CT scans indicate these patients are severe COVID-19 patients who were admitted to ICU. The inflammatory cytokines and immune cells in peripheral blood of these patients were detected. All the patients were admitted in ICU with hypoxemic respiratory failure. The comorbidities are hypertension (20%; 5/25) and diabetes (20%; 5/25). All of these 25 surviving patients were discharged from the ICU to hospital ward before being discharged home. As showed in the Table 1 , inflammatory cytokines including C reactive protein, IL-2, IL-4, IL-10, TNF-α and IFN-γ were in the normal value range compared to the reference value. These cases showed that IL-2, IL-4, TNF-α, IFN-γ and C reactive protein level is not associated with severe COVID-19 pathology. However, IL-6 and IL-10 level of some severe COVID-19 patients is over to the reference value. These indicate these COVID-19 patients has severe clinical characteristics independent on circulating levels of inflammatory cytokines in peripheral blood including of IL-2, IL-4, TNF-α, IFN-γ and C reactive protein. prognostic prediction based on machine learning tools (12) . In our study, C reactive protein is in the normal range in all patients who were admitted to ICU and all of these patients are surviving. Our observation is consistent with reports indicating C reactive protein as biomarkers COVID-19 mortality (12) . Dissertation of the level and role of proinflammatory cytokines in the pathophysiology of COVID-19 is critical for evaluation anticytokine therapy. At present, very limited experience on cytokine inhibitors affects COVID-19 patients. SARS-CoV-2 might well adapt for humans and the viral genomic RNA or the intermediates can ' t be recognized by immune sysytem for activation downstream inflammation cascades. Our study emphasizes circulating levels of IL-2, IL-4, TNF-α, IFN-γ and C reactive protein are not associated with severity of COVID-19 symptoms. To address why severe COVID-19 is independent on inflammation response that would be a fundamental question for us to understand of COVID-19 pathophysiology. COVID-19 has disparate features in term of severity, mortality and spread across countries. A striking variation in mortality rates has been observed in different countries (13) . Enormous differences in human leukocyte antigen (HLA) haplotype might confer the This article is protected by copyright. All rights reserved. different immune response to SARS-CoV-2, which leads to the variation in severity, mortality and spread rates of COVID-19 (14) . However, the causation of COVID-19 severity and mortality requires more investigation. Some reports showed cytokine storm is correlated with severity and mortality of COVID-19 patients (5, 7, 8) . But the correlation does not indicate causation. More viral replication also could drive consequent severity of COVID-19. Janus kinase (JAK) inhibitors targeting cytokines with JAK-dependent signaling was thought to be potential to restrain the excessive level of cytokine signaling (15) . Currently, IL-6R and IL-6 inhibitors were used in COVID-19 patients which has already been launched. Experts hope IL-6R and IL-6 inhibitors could inhibit hyperinflammatory response in COVID-19 patients independent on viral clearance (16) . The hypothesis that blocking cytokine storm eases COVID-19 severity needs to be more careful investigation based on our observation. At least, each patients should be tested circulating levels of inflammatory cytokines before launching anti-inflammatory treatment. ICU: Intensive care unit CRP: C reactive protein All co-authors have approved the manuscript and agreed with the publication. Each patient consents to participate in this study. Not applicable. The authors have no conflict of interest to declare. This article is protected by copyright. All rights reserved. Funding This work was supported by grants from the State Key Laboratory of Veterinary Biotechnology (No. 2020901 to Q.W.) Authors' contributions QW conceptualized the study. QW and WL analyzed the data. WL and JZ contributed to manuscript preparation. WL, WZ and YL collected the patients information. QW wrote the first draft of the manuscript. All of the authors contributed to revising the manuscript, and read and approved the final version for publication. Factors Affecting the Tissue Damaging Consequences of Viral Infections Antiviral drug resistance: mechanisms and clinical implications Cytokines in Inflammatory Disease Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China Hlh Across Speciality Collaboration UK. COVID-19: consider cytokine storm syndromes and immunosuppression COVID-19 cytokine storm: the interplay between inflammation and coagulation Cytokine storm syndrome in severe COVID-19 The cytokine storm in COVID-19: An overview of the involvement of the chemokine/chemokine-receptor system Endothelial cell infection and endotheliitis in COVID-19 Pathological findings of COVID-19 associated with acute respiratory distress syndrome COVID19 coagulopathy in Caucasian patients An interpretable mortality prediction model for COVID-19 patients Sasanka Chakrabarti. COVID-19 in India: Are Biological and Environmental Factors Helping to Stem the Incidence and Severity? Aging and Disease COVID-19 infection: the perspectives on immune responses HiJAKing SARS-CoV-2? The potential role of JAK inhibitors in the management of COVID-19 COVID-19: risk for cytokine targeting in chronic inflammatory diseases? The reference value of serum IL-2 levels is 0.08-5.71 pg/ml. The reference value of serum IL-4 levels is 0.1-2.8 pg/L. The reference value of serum IL-6 levels is 1.18-5.3 pg/L. The reference value of serum IL The reference value of serum IFN-γ levels is 0.16-7.42 pg/L. The reference value of serum C reactive protein (CRP) levels is 0-10 mg/L. The reference value of T4 (CD4+ T cells) is 404-1612. The reference value of T8 (CD8+ T cells) is 220-1129. The reference value of NK cells is 150-1100. The reference value of B cells is 90-560. The cytokines and CRP were detected by automatic immunofluorescence analyzer (Jet-iStar 3000, JOINSTAR, China) and the reagent is a supporting product by the same company. To determine the immune cells count We thank the physicians and nurses in First Affiliated Hospital who cared these patients and made this study possible.