Cytokine Storm Syndrome.

Cytokine storm syndrome (CSS), which is frequently fatal, has garnered increased attention with the ongoing coronavirus pandemic. A variety of hyperinflammatory conditions associated with multiorgan system failure can be lumped under the CSS umbrella, including familial hemophagocytic lymphohistiocytosis (HLH) and secondary HLH associated with infections, hematologic malignancies, and autoimmune and autoinflammatory disorders, in which case CSS is termed macrophage activation syndrome (MAS). Various classification and diagnostic CSS criteria exist and include clinical, laboratory, pathologic, and genetic features. Familial HLH results from cytolytic homozygous genetic defects in the perforin pathway employed by cytotoxic CD8 T lymphocytes and natural killer (NK) cells. Similarly, NK cell dysfunction is often present in secondary HLH and MAS, and heterozygous mutations in familial HLH genes are frequently present. Targeting overly active lymphocytes and macrophages with etoposide and glucocorticoids is the standard for treating HLH; however, more targeted and safer anticytokine (e.g., anti-interleukin-1, -6) approaches are gaining traction as effective alternatives.

Cytokine storm syndrome after anti-thymoglobulin infusion in a cynomolgus monkey with systemic lymphadenopathy caused by follicular hyperplasia: A case report.

Nonhuman primates are widely used in transplantation research as preclinical xeno- or allo-transplantation models. Rabbit anti-thymoglobulin (ATG) is often used for T-cell depletion as an immunosuppressant. T-cell depletion can cause a secondary cytokine storm syndrome that can be minimized/prevented by a prophylactic administration of systemic corticosteroids and antihistamines. We report a case of death due to CSS in a cynomolgus monkey with follicular hyperplasia-induced systemic lymphadenopathy after ATG administration. A 6-year-old female cynomolgus monkey was rendered diabetic and then transplanted with a genetically modified porcine pancreatic islets (PPI) (50 000 IEQ/kg) through the portal vein 22 days later without immunosuppressant. Because graft function was not comparable, we planned re-transplantation of PPI. For re-transplantation of the PPI, we performed an intravenous (IV) ATG infusion for inductive immunosuppression. The monkey died 3 h and 30 min after ATG administration despite cardiopulmonary resuscitation. Systemic lymphadenopathy was observed on submandibular, axillary, inguinal, foregut, colic, and hilar lymph nodes, and splenomegaly was also observed on necropsy. Histopathologic examination of the lymph node revealed follicular hyperplasia. The IL-6 level was higher after ATG infusion compared to before ATG infusion (before vs. after ATG infusion; 14.9 vs. >5000 pg/mL). The death of the cynomolgus monkey was caused by severe CSS because of apoptosis of B cells in the systemic lymph nodes caused by the ATG administration. A thorough physical examination of palpable lymph nodes and pre-ATG sonographic or computed tomographic screening could have identified lymphadenopathy, potentially preventing its infusion and reducing mortality risk.

Single dose tocilizumab for COVID-19 associated cytokine storm syndrome: Less is more.

AIMS: We aim to evaluate the clinical pharmacokinetics of a single dose interleukin-6 (IL-6) antibody tocilizumab (TCZ) in methylprednisolone (MP)-treated COVID-19 patients with cytokine storm syndrome (CSS). METHODS: MP pre-treated patients with COVID-19-associated CSS, defined as at least two elevations of C-reactive protein (CRP) >100 mg/L, ferritin >900 µg/L or D-dimers >1500 µg/L, received intravenous TCZ (8 mg/kg, max. 800 mg) upon clinical deterioration. A nonlinear-mixed effects model was developed based on TCZ serum concentrations and dosing information. Population pharmacokinetic parameters were estimated and concentration-time profiles were plotted against individual predicted values. Fixed dose simulations were subsequently performed based on the final model. RESULTS: In total 40 patients (mean [SD] age: 62 [12] years, 20% female, body weight: 87 [17] kg) with COVID-19 induced CSS were evaluated on pharmacokinetics and laboratory parameters. A biphasic elimination of TCZ serum concentration was described by a homogeneous population pharmacokinetic model. Serum TCZ concentrations above the 1 µg/L target saturation threshold were covered for 16 days in all evaluated patients treated with a single dose of 8 mg/kg. In a simulation with TCZ 400 mg fixed dose, this condition of full IL-6 receptor occupancy at minimum serum concentration was also met. CONCLUSIONS: A single dose (8 mg/kg, max. 800 mg) is sufficient to cover a period of 16 days of IL-6-mediated hyperinflammation in COVID-19-induced CSS in MP-treated patients. Based on body weight PK simulations, a fixed-dose tocilizumab of 400 mg should be considered to prevent overtreatment, future drug shortage and unnecessary drug expenditure.

Inflammatory diseases in hematology: a review.

Hematopoietic cells are instrumental in generating and propagating protective inflammatory responses to infection or injury. However, excessive inflammation contributes to many diseases of the blood, bone marrow, and lymphatic system. We review three clinical categories of hematological inflammatory diseases in which recent clinical and translational advances have been made. The first category is monogenic inflammatory diseases. Genotype-driven research has revealed that previously mysterious diseases with protean manifestations are characterized by mutations that may be germline (e.g., deficiency of ADA2 or GATA2 deficiency) or somatic [e.g., vacuoles, enzyme E1, X-linked, autoinflammatory, somatic (VEXAS) syndrome]. The second category is the cytokine storm syndromes, including hemophagocytic lymphohistiocytosis, and Castleman disease. Cytokine storm syndromes are characterized by excessive production of inflammatory cytokines including interleukin-6 and interferon-γ, causing end-organ damage and high mortality. Finally, we review disorders associated with monoclonal and polyclonal hypergammaglobulinemia. The serum protein electrophoresis (SPEP) is typically ordered to screen for common diseases such as myeloma and humoral immunodeficiency. However, monoclonal and polyclonal hypergammaglobulinemia on SPEP can also provide important information in rare inflammatory diseases. For example, the autoinflammatory disease Schnitzler syndrome is notoriously difficult to diagnose. Although this orphan disease has eluded precise genetic or histological characterization, the presence of a monoclonal paraprotein, typically IgM, is an obligate diagnostic criterion. Likewise, polyclonal hypergammaglobulinemia may be an important early, noninvasive diagnostic clue for patients presenting with rare neoplastic diseases such as Rosai-Dorfman disease and angioimmunoblastic T-cell lymphoma. Applying these three categories to patients with unexplained inflammatory syndromes can facilitate the diagnosis of rare and underrecognized diseases.

Cytokine profile, ferritin and multi-visceral involvement characterize macrophage activation syndrome during adult-onset Still's disease.

OBJECTIVES: To multidimensionally characterize macrophage activation syndrome (MAS) complicating adult-onset Still's disease (AOSD) considering cytokine profile, inflammatory markers and multi-visceral involvement of the disease. To perform a high-dimensional phenotypic analysis of circulating immune cells in AOSD patients with and without MAS. To assess interferon (IFN)-related pathways in AOSD synovial tissues by a bulky RNA sequencing. METHODS: Clinical and biologic data were collected and compared in AOSD patients with and without MAS. Sera biomolecules were analysed by Luminex multiplexing technology. Mass cytometry (CyTOF) was used to characterize circulating immune cells. A bulky RNA sequencing was performed in AOSD synovial tissues. RESULTS: Forty consecutive AOSD patients were assessed, 14 complicated with MAS. Paralleling with increases of systemic score and ferritin, MAS patients showed higher levels of IL-1α, IL-1ß, IL-1Ra, IL-2Ra, IL-6, IL-10, IL-17A, IFN-γ, G-CSF, MCP-1, MIP-1α and SCF. Combining the discriminatory ability of these data in identifying MAS, the best model was composed by systemic score, ferritin, IFN-γ and IL-10. By CyTOF analysis, MAS patients showed an increase of circulating 'classical monocytes' and a reduction of total NK cells. Our assessment showed 3477 IFN-related genes (IRGs) were differently expressed in AOSD synovial tissues. CONCLUSIONS: A multidimensional characterization of AOSD patients suggested that IFN-γ, IL-10, ferritin and systemic score discriminated the occurrence of cytokine storm syndrome associated with MAS. The inflammatory milieu of AOSD and MAS may be related to a signature of circulating immune cells. Finally, our results about IRGs reinforced the role of IFN-γ in these patients.

Role of therapeutic plasma exchange in the management of COVID-19-induced cytokine storm syndrome.

The risk of mortality in patients with coronavirus disease 2019 (COVID-19) is largely related to an excessive immune response, resulting in a hyperinflammatory and hypercoagulable condition collectively referred to as cytokine storm syndrome (CSS). Management of critically ill patients with COVID-19 has included attempts to abate this process, prevent disease progression, and reduce mortality. In this context, therapeutic plasma exchange (TPE) offers an approach to eliminate inflammatory factors and cytokines, offset the pathologic coagulopathy, and reduce the CSS effects. The aim of this review is to analyze available data on the use of TPE for the treatment of CSS in patients with COVID-19. Systematic searches of PubMed, Scopus and COVID-19 Research were conducted to identify articles published between March 1, 2020 and May 26, 2021 reporting the use of TPE for the treatment of COVID-19-induced CSS. A total of 34 peer-reviewed articles (1 randomized controlled trial, 4 matched case-control series, 15 single-group case series, and 14 case reports), including 267 patients, were selected. Despite the low evidence level of the available data, TPE appeared to be a safe intervention for critically ill patients with COVID-19-induced CSS. Although inconsistencies exist between studies, they showed a general trend for decreased interleukin-6, C-reactive protein, ferritin, D-dimer, and fibrinogen levels and increased lymphocyte counts following TPE, supporting the immunomodulatory effect of this treatment. Moreover, TPE was associated with improvements in clinical outcomes in critically ill patients with COVID-19. While TPE may offer a valuable option to treat patients with COVID-19-induced CSS, high-quality randomized controlled clinical trials are needed to confirm its potential clinical benefits, feasibility, and safety. Moreover, clear criteria should be established to identify patients with CSS who might benefit from TPE.

Comprehensive Cytokine Profiling of Patients with COVID-19 Receiving Tocilizumab Therapy.

Coronavirus disease 2019 (COVID-19) is characterized by immune activation in response to viral spread, in severe cases leading to the development of cytokine storm syndrome (CSS) and increased mortality. Despite its importance in prognosis, the pathophysiological mechanisms of CSS in COVID-19 remain to be defined. Towards this goal, we analyzed cytokine profiles and their interrelation in regard to anti-cytokine treatment with tocilizumab in 98 hospitalized patients with COVID-19. We performed a multiplex measurement of 41 circulating cytokines in the plasma of patients on admission and 3-5 days after, during the follow-up. Then we analyzed the patient groups separated in two ways: according to the clusterization of their blood cytokines and based on the administration of tocilizumab therapy. Patients with and without CSS formed distinct clusters according to their cytokine concentration changes. However, the tocilizumab therapy, administered based on the standard clinical and laboratory criteria, did not fully correspond to those clusters of CSS. Furthermore, among all cytokines, IL-6, IL-1RA, IL-10, and G-CSF demonstrated the most prominent differences between patients with and without clinical endpoints, while only IL-1RA was prognostically significant in both groups of patients with and without tocilizumab therapy, decreasing in the former and increasing in the latter during the follow-up period. Thus, CSS in COVID-19, characterized by a correlated release of multiple cytokines, does not fully correspond to the standard parameters of disease severity. Analysis of the cytokine signature, including the IL-1RA level in addition to standard clinical and laboratory parameters may be useful to define the onset of a cytokine storm in COVID-19 as well as the indications for anti-cytokine therapy.

Biomarkers in Systemic Juvenile Idiopathic Arthritis, Macrophage Activation Syndrome and Their Importance in COVID Era.

Systemic juvenile idiopathic arthritis (sJIA) and its complication, macrophage activation syndrome (sJIA-MAS), are rare but sometimes very serious or even critical diseases of childhood that can occasionally be characterized by nonspecific clinical signs and symptoms at onset-such as non-remitting high fever, headache, rash, or arthralgia-and are biologically accompanied by an increase in acute-phase reactants. For a correct positive diagnosis, it is necessary to rule out bacterial or viral infections, neoplasia, and other immune-mediated inflammatory diseases. Delays in diagnosis will result in late initiation of targeted therapy. A set of biomarkers is useful to distinguish sJIA or sJIA-MAS from similar clinical entities, especially when arthritis is absent. Biomarkers should be accessible to many patients, with convenient production and acquisition prices for pediatric medical laboratories, as well as being easy to determine, having high sensitivity and specificity, and correlating with pathophysiological disease pathways. The aim of this review was to identify the newest and most powerful biomarkers and their synergistic interaction for easy and accurate recognition of sJIA and sJIA-MAS, so as to immediately guide clinicians in correct diagnosis and in predicting disease outcomes, the response to treatment, and the risk of relapses. Biomarkers constitute an exciting field of research, especially due to the heterogeneous nature of cytokine storm syndromes (CSSs) in the COVID era. They must be selected with utmost care-a fact supported by the increasingly improved genetic and pathophysiological comprehension of sJIA, but also of CSS-so that new classification systems may soon be developed to define homogeneous groups of patients, although each with a distinct disease.

Selected severe „haematological“ syndromes in adult intensive care patients.

Haemophagocytic syndrome, diffuse alveolar haemorrhage, catastrophic antiphospholipid syndrome and various types of thrombotic microangiopathies are rare conditions with significant morbidity and mortality. A common feature is late diagnosis, which can affect the success of treatment. The aim of this review article is to summarize the basic diagnostic and therapeutic steps of the present subpopulation of critically ill patients.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) Encephalitis Is a Cytokine Release Syndrome: Evidences From Cerebrospinal Fluid Analyses.

BACKGROUND: Recent findings indicated that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related neurological manifestations involve cytokine release syndrome along with endothelial activation, blood brain barrier dysfunction, and immune-mediated mechanisms. Very few studies have fully investigated the cerebrospinal fluid (CSF) correlates of SARS-CoV-2 encephalitis. METHODS: Patients with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 infection and encephalitis (COV-Enc), encephalitis without SARS-CoV-2 infection (ENC), and healthy controls (HC) underwent an extended panel of CSF neuronal (neurofilament light chain [NfL], T-tau), glial (glial fibrillary acidic protein [GFAP], soluble triggering receptor expressed on myeloid cells 2 [sTREM2], chitinase-3-like protein 1 [YKL-40]) and inflammatory biomarkers (interleukin [IL]-1ß, IL-6, Il-8, tumor necrosis factor [TNF] α, CXCL-13, and ß2-microglobulin). RESULTS: Thirteen COV-Enc, 21 ENC, and 18 HC entered the study. In COV-Enc cases, CSF was negative for SARS-CoV-2 real-time PCR but exhibited increased IL-8 levels independently from presence of pleocytosis/hyperproteinorracchia. COV-Enc patients showed increased IL-6, TNF- α, and ß2-microglobulin and glial markers (GFAP, sTREM2, YKL-40) levels similar to ENC but normal CXCL13 levels. Neuronal markers NfL and T-tau were abnormal only in severe cases. CONCLUSIONS: SARS-CoV-2-related encephalitis were associated with prominent glial activation and neuroinflammatory markers, whereas neuronal markers were increased in severe cases only. The pattern of CSF alterations suggested a cytokine-release syndrome as the main inflammatory mechanism of SARS-CoV-2-related encephalitis.

Cytokine storm syndrome in coronavirus disease 2019: A narrative review.

Cytokine storm syndrome (CSS) is a critical clinical condition induced by a cascade of cytokine activation, characterized by overwhelming systemic inflammation, hyperferritinaemia, haemodynamic instability and multiple organ failure (MOF). At the end of 2019, the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, China, and rapidly developed into a global pandemic. More and more evidence shows that there is a dramatic increase of inflammatory cytokines in patients with COVID-19, suggesting the existence of cytokine storm in some critical illness patients. Here, we summarize the pathogenesis, clinical manifestation of CSS, and highlight the current understanding about the recognition and potential therapeutic options of CSS in COVID-19.

An Intelligent Graphene-Based Biosensing Device for Cytokine Storm Syndrome Biomarkers Detection in Human Biofluids.

Abnormal elevated levels of cytokines such as interferon (IFN), interleukin (IL), and tumor necrosis factor (TNF), are considered as one of the prognosis biomarkers for indicating the progression to severe or critical COVID-19. Hence, it is of great significance to develop devices for monitoring their levels in COVID-19 patients, and thus enabling detecting COVID-19 patients that are worsening and to treat them before they become critically ill. Here, an intelligent aptameric dual channel graphene-TWEEN 80 field effect transistor (DGTFET) biosensing device for on-site detection of IFN-γ, TNF-α, and IL-6 within 7 min with limits of detection (LODs) of 476 × 10-15 , 608 × 10-15 , or 611 × 10-15 m respectively in biofluids is presented. Using the customized Android App together with this intelligent device, asymptomatic or mild COVID-19 patients can have a preliminary self-detection of cytokines and get a warning reminder while the condition starts to deteriorate. Also, the device can be fabricated on flexible substrates toward wearable applications for moderate or even critical COVID-19 cases for consistently monitoring cytokines under different deformations. Hence, the intelligent aptameric DGTFET biosensing device is promising to be used for point-of-care applications for monitoring conditions of COVID-19 patients who are in different situations.

Macrophage activation syndrome in children with Kawasaki disease: an experience from a tertiary care hospital in northwest India.

OBJECTIVES: To carry out a review of clinical characteristics, laboratory profiles, management and outcomes of patients with Kawasaki disease (KD) and macrophage activation syndrome (MAS). METHODS: Medical records of patients treated for KD and MAS between January 1994 and December 2019 were reviewed. Patient demographics, clinical signs, laboratory values, coronary artery abnormalities, treatments and outcomes of patients with KD and MAS were recorded. We also performed a review published studies on the subject. RESULTS: Of the 950 cases with KD, 12 (1.3%; 10 boys, 2 girls) were diagnosed with MAS. The median age at diagnosis was 4 years (range 9 months-7.5 years). The median interval between onset of fever and diagnosis of KD was 11 days (range 6-30). Thrombocytopenia was seen in 11 patients. The median pro-brain natriuretic peptide value was 2101 pg/ml (range 164-75 911). Coronary artery abnormalities were seen in 5 (41.7%) patients; 2 had dilatation of the left main coronary artery (LMCA), 1 had dilatation of both the LMCA and right coronary artery (RCA), 1 had dilatation of the RCA and 1 had bright coronary arteries. All patients received IVIG as first-line therapy for KD. MAS was treated with i.v. methylprednisolone pulses followed by tapering doses of oral prednisolone. Additional therapy included i.v. infliximab (n = 4), second-dose IVIG (n = 1) and oral ciclosporin (n = 1). CONCLUSION: MAS is an unusual and underrecognized complication of KD. In our cohort of 950 patients with KD, 1.3% had developed MAS. KD with MAS is associated with an increased propensity towards development of coronary artery abnormalities.

COVID-19 and hepatic involvement: The liver as a main actor of the pandemic novel.

In the natural history of SARS-CoV-2 infection, liver injury is frequent but quite mild and it is defined as any liver damage occurring during disease progression and treatment of infection in patients with or without pre-existing liver diseases. The underlying mechanisms for hepatic injury in patients with COVID-19 are still unclear but the liver damage in SARS-CoV-2 infection seems to be directly caused by virus-induced cytopathic effects. In this review, we will summarize all data of updated literature, regarding the relationship between SARS-CoV-2 infection, acute response and liver involvement. An overview will be given on liver injury, liver transplant and the possible consequences of COVID-19 in patients with pre-existing liver diseases.

Role of ACE2 receptor and the landscape of treatment options from convalescent plasma therapy to the drug repurposing in COVID-19.

Since the first case reports in Wuhan, China, the SARS-CoV-2 has caused a pandemic and took lives of > 8,35,000 people globally. This single-stranded RNA virus uses Angiotensin-converting enzyme 2 (ACE2) as a receptor for entry into the host cell. Overexpression of ACE2 is mainly observed in hypertensive, diabetic and heart patients that make them prone to SARS-CoV-2 infection. Mitigations strategies were opted globally by the governments to minimize transmission of SARS-CoV-2 via the implementation of social distancing norms, wearing the facemasks, and spreading awareness using digital platforms. The lack of an approved drug treatment regimen, and non-availability of a vaccine, collectively posed a challenge for mankind to fight against the SARS-CoV-2 pandemic. In this scenario, repurposing of existing drugs and old treatment options like convalescent plasma therapy can be one of the potential alternatives to treat the disease. The drug repurposing provides a selection of drugs based on the scientific rationale and with a shorter cycle of clinical trials, while plasma isolated from COVID-19 recovered patients can be a good source of neutralizing antibody to provide passive immunity. In this review, we provide in-depth analysis on these two approaches currently opted all around the world to treat COVID-19 patients. For this, we used "Boolean Operators" such as AND, OR & NOT to search relevant research articles/reviews from the PUBMED for the repurposed drugs and the convalescent plasma in the COVID-19 treatment. The repurposed drugs like Chloroquine and Hydroxychloroquine, Tenofovir, Remdesivir, Ribavirin, Darunavir, Oseltamivir, Arbidol (Umifenovir), Favipiravir, Anakinra, and Baricitinib are already being used in clinical trials to treat the COVID-19 patients. These drugs have been approved for a different indication and belong to a diverse category such as anti-malarial/anti-parasitic, anti-retroviral/anti-viral, anti-cancer, or against rheumatoid arthritis. Although, the vaccine would be an ideal option for providing active immunity against the SARS-CoV-2, but considering the current situation, drug repurposing and convalescent plasma therapy and repurposed drugs are the most viable option against SARS-CoV-2.

The treatment of SARS-CoV2 with antivirals and mitigation of the cytokine storm syndrome: the role of gene expression.

In the absence of a vaccine, the treatment of SARS-CoV2 has focused on eliminating the virus with antivirals or mitigating the cytokine storm syndrome (CSS) that leads to the most common cause of death: respiratory failure. Herein we discuss the mechanisms of antiviral treatments for SARS-CoV2 and treatment strategies for the CSS. Antivirals that have shown in vitro activity against SARS-CoV2, or the closely related SARS-CoV1 and MERS-CoV, are compared on the enzymatic level and by potency in cells. For treatment of the CSS, we discuss medications that reduce the effects or expression of cytokines involved in the CSS with an emphasis on those that reduce IL-6 because of its central role in the development of the CSS. We show that some of the medications covered influence the activity or expression of enzymes involved in epigenetic processes and specifically those that add or remove modifications to histones or DNA. Where available, the latest clinical data showing the efficacy of the medications is presented. With respect to their mechanisms, we explain why some medications are successful, why others have failed, and why some untested medications may yet prove useful.

Hemocytometric characteristics of COVID-19 patients with and without cytokine storm syndrome on the sysmex XN-10 hematology analyzer.

OBJECTIVES: COVID-19 is an ongoing global pandemic. There is an urgent need for identification and understanding of clinical and laboratory parameters related to progression towards a severe and fatal form of this illness, often preceded by a so-called cytokine-storm syndrome (CSS). Therefore, we explored the hemocytometric characteristics of COVID-19 patients in relation to the deteriorating clinical condition CSS, using the Sysmex XN-10 hematology analyzer. METHODS: From March 1st till May 16th, 2020, all patients admitted to our hospital with respiratory complaints and suspected for COVID-19 were included (n=1,140 of whom n=533 COVID-19 positive). The hemocytometric parameters of immunocompetent cells in peripheral blood (neutrophils [NE], lymphocytes [LY] and monocytes [MO]) obtained upon admission to the emergency department (ED) of COVID-19 positive patients were compared with those of the COVID-19 negative ones. Moreover, patients with CSS (n=169) were compared with COVID-19 positive patients without CSS, as well as with COVID-19 negative ones. RESULTS: In addition to a significant reduction in leukocytes, thrombocytes and absolute neutrophils, it appeared that lymphocytes-forward scatter (LY-FSC), and reactive lymphocytes (RE-LYMPHO)/leukocytes were higher in COVID-19-positive than negative patients. At the moment of presentation, COVID-19 positive patients with CSS had different neutrophils-side fluorescence (NE-SFL), neutrophils-forward scatter (NE-FSC), LY-FSC, RE-LYMPHO/lymphocytes, antibody-synthesizing (AS)-LYMPHOs, high fluorescence lymphocytes (HFLC), MO-SSC, MO-SFL, and Reactive (RE)-MONOs. Finally, absolute eosinophils, basophils, lymphocytes, monocytes and MO-FSC were lower in patients with CSS. CONCLUSIONS: Hemocytometric parameters indicative of changes in immunocompetent peripheral blood cells and measured at admission to the ED were associated with COVID-19 with and without CSS.

Effects of different concentrations of mesenchymal stem cells treatment on LPS-induced acute respiratory distress syndrome rat model.

PURPOSE: This study was prospectively designed to investigate the effects of different concentrations of mesenchymal stem cells treatment on respiratory mechanics, oxygenation, hemodynamics and inflammatory response in LPS-induced acute respiratory distress syndrome (ARDS) rat model. Methods: One hundred and twenty six LPS-induced ARDS model rats (weighted 200-220 g) were randomly divided into three groups: 1) Control group (N = 42); 2) low-dose hUC-MSC treatment group (MSC group 1, 1x107 cell/kg, N = 42); 3) high-dose hUC-MSC treatment group (MSC group 2, 2x107 cell/kg, N = 42), sham operation group as healthy group (N = 15). The rats were observed closely for 24 hours after hUC-MSC treatment, and the survival rate was calculated. At 24 hours, all rats were tested for hemodynamics, blood gas analysis, heart, lung, liver and kidney functions, inflammatory factors detection in blood samples and broncho-alveolar lavage fluid (BALF). The lung tissue of the rats was collected for HE staining analysis. Results: After LPS injection, ARDS was obvious in all LPS-infused rat groups, consistent with severe acute lung injury and high death rate. However, compared with the control group, a single intravenous injection hUC-MSC at dose of 1 × 107 cells/kg (low dose group) and 2 × 107 cells/kg (high dose group) reduced the mortality of rats with LPS-induced ARDS, as well as improving the lung function, increased the arterial oxygen pressure, improved the heart function, and reduced the levels of inflammatory factors including IL-1ß, IL-6, and TNF-α. In addition, the high dose MSC group showed better lung injury therapeutic effects than the low dose MSC group. Data from this study demonstrated that injection of hUC-MSC had a significant therapeutic effect in treating the rat model of LPS-induced ARDS and multiple organ function injury.

Macrophage biomimetic nanocarriers for anti-inflammation and targeted antiviral treatment in COVID-19.

BACKGROUND: The worldwide pandemic of COVID-19 remains a serious public health menace as the lack of efficacious treatments. Cytokine storm syndrome (CSS) characterized with elevated inflammation and multi-organs failure is closely correlated with the bad outcome of COVID-19. Hence, inhibit the process of CSS by controlling excessive inflammation is considered one of the most promising ways for COVID-19 treatment. RESULTS: Here, we developed a biomimetic nanocarrier based drug delivery system against COVID-19 via anti-inflammation and antiviral treatment simultaneously. Firstly, lopinavir (LPV) as model antiviral drug was loaded in the polymeric nanoparticles (PLGA-LPV NPs). Afterwards, macrophage membranes were coated on the PLGA-LPV NPs to constitute drugs loaded macrophage biomimetic nanocarriers (PLGA-LPV@M). In the study, PLGA-LPV@M could neutralize multiple proinflammatory cytokines and effectively suppress the activation of macrophages and neutrophils. Furthermore, the formation of NETs induced by COVID-19 patients serum could be reduced by PLGA-LPV@M as well. In a mouse model of coronavirus infection, PLGA-LPV@M exhibited significant targeted ability to inflammation sites, and superior therapeutic efficacy in inflammation alleviation and tissues viral loads reduction. CONCLUSION: Collectively, such macrophage biomimetic nanocarriers based drug delivery system showed favorable anti-inflammation and targeted antiviral effects, which may possess a comprehensive therapeutic value in COVID-19 treatment.

Hemophagocytic lymphohistiocytosis: a review inspired by the COVID-19 pandemic.

Hemophagocytic syndrome (HPS) or hemophagocytic lymphohistiocytosis (HLH) is an acute and rapidly progressive systemic inflammatory disorder characterized by cytopenia, excessive cytokine production, and hyperferritinemia. Common clinical manifestations of HLH are acute unremitting fever, lymphadenopathy, hepatosplenomegaly, and multiorgan failure. Due to a massive cytokine release, this clinical condition is considered as a cytokine storm syndrome. HPS has primary and acquired (secondary, reactive) forms. Its primary form is mostly seen in childhood and caused by various mutations with genetic inheritance and, therefore, is called familial HLH. Secondary HLH may be caused in the presence of an underlying disorder, that is, secondary to a malignant, infectious, or autoimmune/autoinflammatory stimulus. This paper aims to review the pathogenesis and the clinical picture of HLH, and its severe complication, the cytokine storm, with a special emphasis on the developed classification criteria sets for rheumatologists, since COVID-19 infection has clinical symptoms resembling those of the common rheumatologic conditions and possibly triggers HLH. MED-LINE/Pubmed was searched from inception to April 2020, and the following terms were used for data searching: "hemophagocytic syndrome" OR "macrophage activation syndrome" OR "hemophagocytic lymphohistiocytosis", OR "cytokine storm". Finally, AND "COVID-19" was included in this algorithm. The selection is restricted to the past 5 years and limited numbers of earlier key references were manually selected. Only full-text manuscripts, published in an English language peer-reviewed journal were included. Manuscript selection procedure and numbers are given in Fig. 2. Briefly, the database search with the following terms of "Hemophagocytic syndrome" OR "Macrophage activation syndrome" OR "Hemophagocytic lymphohistiocytosis" OR "Cytokine storm" yielded 6744 results from inception to April 2020. The selection is restricted to the past 5 years and only limited numbers of earlier key references were selected, and this algorithm resulted in 3080 manuscripts. The addition of (AND "COVID-19") resulted in 115 publications of which 47 studies, together with four sections of an online book were used in the final review. No statistical method was used. HLH is triggered by genetic conditions, infections, malignancies, autoimmune-autoinflammatory diseases, and some drugs. In COVID-19 patients, secondary HLH and cytokine storm may be responsible for unexplained progressive fever, cytopenia, ARDS, neurological and renal impairment. Differentiation between the primary and secondary forms of HLH is utterly important, since primary form of HLH requires complicated treatments such as hematopoietic stem cell transplantation. Further studies addressing the performance of HScore and other recommendations in the classification of these patients is necessary.