Neutrophil-to-lymphocyte ratio an inflammatory biomarker, and prognostic marker in heart failure, cardiovascular disease and chronic inflammatory diseases: New insights for a potential predictor of anti-cytokine therapy responsiveness

In the 20th century, research focused on cholesterol and lipoproteins as the key mechanism in establishing atherosclerotic cardiovascular disease (ASCVD). Given that some studies demonstrated subclinical atherosclerosis in subjects without conventional cardiovascular risk factors, the elevated low-density lipoprotein (LDL) levels alone cannot account for the entire burden of atherosclerosis. Hence, large-scale clinical trials demonstrated the operation of immune and inflammatory pathways in ASCVD. In this regard, the evidence establishes that cells of the immune system, both the innate (neutrophils, macrophages) and adaptive (T cell and other lymphocytes) limbs, contribute to atherosclerosis and atherothrombosis. Besides, basic science studies have identified proatherogenic cytokines such as interleukin (IL)-1, IL-12, and IL-18. In this regard, some studies showed that antiinflammatory therapy targeting the immune system by modulating or blocking interleukins, also known as anti-cytokine therapy, can reduce the risk of major cardiovascular adverse events. The neutrophils play a key role in the innate immune system, representing the acute phase of an inflammatory response. In contrast, lymphocytes represent the adaptive immune system and promote the induction of autoimmune inflammation, especially in the chronic inflammatory response. Through the literature review, we will highlight the inflammatory pathway for the physiopathology of ASCVD, HF, and COVID-19. In this regard, the neutrophil-to-lymphocyte ratio (NLR) integrates the innate immune and adaptive immune systems, making the NLR a biomarker of inflammation. In addition, we provided an update on the evidence showing that high NLR is associated with worse prognosis in heart failure (HF), ASCVD, and COVID-19, as well as their clinical applications showing that the normalization of NLR after anti-cytokine therapy is a potential predictor of therapy responsiveness and is associated with reduction of major adverse cardiovascular events.

Anti-cytokine Therapy in Hospitalized Patients with COVID-19: The Jury is Out

How to cite this article: Garg SK. Anti-cytokine Therapy in Hospitalized Patients with COVID-19: The Jury is Out. Indian J Crit Care Med 2022;26(10):1069-1071.

Anakinra for the treatment of adult secondary HLH: a retrospective experience

Anti-cytokine therapies have been gaining attention as a means of improving outcomes in adult secondary HLH (asHLH), which currently has poor outcomes when treated with standard etoposide-based therapies. Anakinra is an interleukin-1 antagonist that is increasingly being used in the management of asHLH. Here is described a multi-hospital series of 16 adult patients with secondary HLH treated with anakinra. Provoking factors of secondary HLH included hematologic malignancy (n = 7, 44%), bacterial infection (n = 7, 44%), viral infection (n = 5, 31%), rheumatologic disorder (n = 4, 25%), and unknown (n = 1, 6%). Five patients remained alive at time of last follow-up (OS = 31%). Median OS was 1.7 months from initiation of anakinra (range 0.2–59). OS among patients with rheumatologic causes of secondary HLH was 75%, whereas only 17% of patients with other provoking factors survived (p = 0.0293). Anakinra was well tolerated, with only 1 patient experiencing associated toxicity (grade 3 liver injury). Anakinra may be useful in the management of asHLH provoked by rheumatologic conditions, although its benefit in asHLH provoked by other factors may be limited.

Ruxolitinib versus dexamethasone in hospitalized adults with COVID-19: multicenter matched cohort study

BACKGROUND

Several anti-cytokine therapies were tested in the randomized trials in hospitalized patients with severe acute respiratory syndrome coronavirus 2 infection (COVID-19). Previously, dexamethasone demonstrated a reduction of case-fatality rate in hospitalized patients with respiratory failure. In this matched control study we compared dexamethasone to a Janus kinase inhibitor, ruxolitinib.

METHODS

The matched cohort study included 146 hospitalized patients with COVID-19 and oxygen support requirement. The control group was selected 1:1 from 1355 dexamethasone-treated patients and was matched by main clinical and laboratory parameters predicting survival. Recruitment period was April 7, 2020 through September 9, 2020.

RESULTS

Ruxolitinib treatment in the general cohort of patients was associated with case-fatality rate similar to dexamethasone treatment: 9.6% (95% CI [4.6-14.6%]) vs 13.0% (95% CI [7.5-18.5%]) respectively (p = 0.35, OR = 0.71, 95% CI [0.31-1.57]). Median time to discharge without oxygen support requirement was also not different between these groups: 13 vs. 11 days (p = 0.13). Subgroup analysis without adjustment for multiple comparisons demonstrated a reduced case-fatality rate in ruxolitnib-treated patients with a high fever (≥ 38.5 °C) (OR 0.33, 95% CI [0.11-1.00]). Except higher incidence of grade 1 thrombocytopenia (37% vs 23%, p = 0.042), ruxolitinib therapy was associated with a better safety profile due to a reduced rate of severe cardiovascular adverse events (6.8% vs 15%, p = 0.025). For 32 patients from ruxolitinib group (21.9%) with ongoing progression of respiratory failure after 72 h of treatment, additional anti-cytokine therapy was prescribed (8-16 mg dexamethasone).

CONCLUSIONS

Ruxolitinib may be an alternative initial anti-cytokine therapy with comparable effectiveness in patients with potential risks of steroid administration. Patients with a high fever (≥ 38.5 °C) at admission may potentially benefit from ruxolitinib administration. Trial registration The Ruxolitinib Managed Access Program (MAP) for Patients Diagnosed With Severe/Very Severe COVID-19 Illness NCT04337359, CINC424A2001M, registered April, 7, 2020. First participant was recruited after registration date.

Immunological analysis of the murine anti-CD3-induced cytokine release syndrome model and therapeutic efficacy of anti-cytokine antibodies

The aberrant release of inflammatory mediators often referred to as a cytokine storm or cytokine release syndrome (CRS), is a common and sometimes fatal complication in acute infectious diseases including Ebola, dengue, COVID-19, and influenza. Fatal CRS occurrences have also plagued the development of highly promising cancer therapies based on T-cell engagers and chimeric antigen receptor (CAR) T cells. CRS is intimately linked with dysregulated and excessive cytokine release, including IFN-γ, TNF-α, IL 1, IL-6, and IL-10, resulting in a systemic inflammatory response leading to multiple organ failure. Here, we show that mice intravenously administered the agonistic hamster anti-mouse CD3ε monoclonal antibody 145-2C11 develop clinical and laboratory manifestations seen in patients afflicted with CRS, including body weight loss, hepatosplenomegaly, thrombocytopenia, increased vascular permeability, lung inflammation, and hypercytokinemia. Blood cytokine levels and gene expression analysis from lung, liver, and spleen demonstrated a hierarchy of inflammatory cytokine production and infiltrating immune cells with differentiating organ-dependent kinetics. IL-2, IFN-γ, TNF-α, and IL-6 up-regulation preceded clinical signs of CRS. The co-treatment of mice with a neutralizing anti-cytokine antibody cocktail transiently improved early clinical and laboratory features of CRS. We discuss the predictive use of this model in the context of new anti-cytokine strategies to treat human CRS.

Impact of interleukin-6 blockade with tocilizumab on SARS-CoV-2 viral kinetics and antibody responses in patients with COVID-19: A prospective cohort study

BACKGROUND

The virological and immunological effects of the immunomodulatory drugs used for COVID-19 remain unknown. We evaluated the impact of interleukin (IL)-6 blockade with tocilizumab on SARS-CoV-2 viral kinetics and the antibody response in patients with COVID-19.

METHODS

Prospective cohort study in patients admitted with COVID-19. Serial nasopharyngeal and plasma samples were measured for SARS-CoV-2 RNA and S-IgG/N-IgG titers, respectively.

FINDINGS

138 patients with confirmed infection were included; 76 (55%) underwent IL-6 blockade. Median initial SOFA (p = 0•016) and SARS-CoV-2 viral load (p<0•001, Mann-Whitney-Wilcoxon test) were significantly higher among anti-IL-6 users. Patients under IL-6 blockade showed delayed viral clearance in the Kaplan-Meier curves (HR 0•35 [95%CI] [0•15-0•81], log-rank p = 0•014), but an adjusted propensity score matching model did not demonstrate a significant relationship of IL-6 blockade with viral clearance (HR 1•63 [0•35-7•7]). Cox regression showed an inverse association between SARS-CoV-2 RNA clearance and the initial viral load (HR 0•35 [0•11-0•89]). Patients under the IL-6 blocker showed shorter median time to seropositivity, higher peak antibody titers, and higher cumulative proportion of seropositivity in the Kaplan Meier curves (HR 3•1 [1•9-5] for S-IgG; and HR 3•0 [1•9-4•9] for N-IgG; log-rank p<0•001 for both). However, no significant differences between groups were found in either S-IgG (HR 1•56 [0•41-6•0]) nor N-IgG (HR 0•96 [0•26-3•5]) responses in an adjusted propensity score analysis.

INTERPRETATION

Our results suggest that in patients infected with SARS-CoV-2, IL-6 blockade does not impair the viral specific antibody responses. Although a delayed viral clearance was observed, it was driven by a higher initial viral load. The study supports the safety of this therapy in patients with COVID-19.

FUNDING

Instituto de salud Carlos III (Spain).

Macrophage activation syndrome and COVID-19

An emerging, rapidly spreading coronavirus SARS-CoV-2 is causing a devastating pandemic. As we have not developed curative medicine and effective vaccine, the end of this life-threatening infectious disease is still unclear. Severe COVID-19 is often associated with hypercytokinemia, which is typically found in macrophage activation syndrome. SARS-CoV-2 infection causes this strong inflammation within the lung and propagates to respiratory and, ultimately, systemic organ malfunction. Although we have not fully understood the physiological and pathological aspects of COVID-19, current research progress indicates the effectiveness of anti-cytokine therapy. Here, we summarize macrophage activation syndrome and its possible contribution to COVID-19, and cytokine targeted attempts in severe COVID-19 cases.

Hypereosinophilic syndrome-a rare adverse event of anti-cytokine treatment in rheumatoid arthritis resolved after Janus kinase inhibitor therapy

Eosinophilia is uncommon in early rheumatoid arthritis (RA). The most frequent causes of hypereosinophilia during RA treatment are atopic eczema, allergy, helminth infection, haematological malignancy and drug-associated complications. The pathogenesis of this abnormality associated with anti-cytokine therapy is still unknown. We report the case of a young woman with RA and eosinophilia accompanied by systemic symptoms such as dyspnoea, fluid retention and eosinophilic vasculitis. An interesting observation was the persistence of eosinophilia during treatment with various biologics and its normalization after switching to the Janus kinase inhibitor baricitinib.

Neurocritical care and target immunotherapy for febrile infection-related epilepsy syndrome

Febrile infection-related epilepsy syndrome (FIRES) is an intractable neurological disease characterized by an unexplained refractory status epilepticus triggered by febrile infection. A Consensus definition of FIRES was proposed in 2018, and its clinical features and prognosis are gradually being clarified. However, the development of effective treatments has been hindered as the etiology of this rare disease is as yet unelucidated. The basic approach to the management of FIRES, like other forms of epilepsy, is based on the control of seizures, however seizures are extremely intractable and require intravenous administration of large doses of anticonvulsants, mainly barbiturates. This treatment strategy produces various complications including respiratory depression and drug hypersensitivity syndrome, which make it more difficult to control seizures. Consequently, it is crucial to predict these events and to formulate a planned treatment strategy. As well, it is important to grow out of conventional treatment strategies that rely on only anticonvulsants, and alternative therapies are gradually being developed. One such example is the adoption of a ketogenic diet which may lead to reduced convulsions as well as improve intellectual prognosis. Further, overproduction of inflammatory cytokines in the central nervous system has been shown to be strongly related to the pathology of FIRES which has led to attempts at immunomodulation therapy including anti-cytokine therapy.

Effect of immunomodulation on cardiac remodelling and outcomes in heart failure: a quantitative synthesis of the literature

Aims

Immunomodulation in heart failure (HF) has been studied in several randomized controlled trials (RCTs) with variable effects on cardiac structure, function, and outcomes. We sought to determine the effect of immunomodulation on left ventricular ejection fraction (LVEF), LV end‐diastolic dimension (LVEDD), and all‐cause mortality in patients with HF with reduced ejection fraction (HFrEF) through meta‐analyses and trial sequential analyses (TSAs) of RCTs.

Methods and results

PubMed, Embase®, Cochrane CENTRAL, and http://ClinicalTrials.gov were systematically reviewed to identify RCTs that studied the effects of immunomodulation in patients with HFrEF. The primary endpoint in this analysis was change in LVEF. Secondary outcomes were changes in LVEDD and all‐cause mortality. TSA was used to quantify the statistical reliability of data in the cumulative meta‐analyses. Nineteen RCTs with 1341 HFrEF subjects were eligible for analyses. The aetiology of HF, specific immunomodulation strategy, and treatment duration were variable across trials. Immunomodulation led to a greater improvement in LVEF [mean difference: +5.7% 95% confidence interval (CI): 3.0–8.5%, P < 0.001] and reduction in LVEDD (mean difference: −3.7 mm, 95% CI: −7.0 to −0.4 mm, P = 0.028) than no immunomodulation in meta‐analyses and TSAs. We observed a non‐significant decrease in all‐cause mortality among those on immumomodulation (risk ratio: 0.7, 95% CI: 0.4–1.3, P = 0.234), but the Z‐curve for cumulative treatment effect of immunomodulation in the TSA did not cross the boundary of futility.

Conclusions

Immunomodulation led to improved cardiac structure and function in patients with HFrEF. While these benefits did not translate into a significant improvement in mortality, our analysis suggests that larger studies of targeted immunomodulation are needed to understand the true benefits.

Mouse models of severe asthma for evaluation of therapeutic cytokine targeting

Severe asthma is a heterogeneous inflammatory disease of the airways, which requires treatment with high-dose inhaled corticosteroids or their systemic administration, yet often remains uncontrolled despite this therapy. Over the past decades, research efforts into phenotyping of severe asthma and defining the pathological mechanisms of this disease were successful largely due to the development of appropriate animal models. Recent identification of distinct inflammatory patterns of severe asthma endotypes led to novel treatment approaches, including targeting specific cytokines or their receptors with neutralizing antibodies. Here we discuss how different experimental mouse models contributed to generation of clinically relevant findings concerning pathogenesis of severe asthma and to identification of potential targets for biologic therapy.

"Hemophagocytic Lymphohistiocytosis after EBV reactivation and ibrutinib treatment in relapsed/refractory Chronic Lymphocytic Leukemia"

Hemophagocytic Lymphohistiocytosis (HLH) is a rare syndrome characterized by ineffective T-cell and NK response. We report the clinical course of a patient with relapsed CLL who developed acute symptoms soon after starting ibrutinib. Hyperpyrexia, splenomegaly, hyperferritinemia, hypertriglyceridemia, cytopenias, and a typical cytokine pattern, i.e. high interleukin (IL)−6, IL10 and IL18, were consistent with a diagnosis of HLH. Coexistent Epstein Barr virus reactivation was documented. Ibrutinib-induced impairment of NK degranulation, associated with EBV reactivation and CLL-related immunodeficiency may have contributed to the development of HLH in our patient.

•

This is the first report describing a case of well-documented HLH in relapsed CLL under ibrutinib.

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There was a strict temporal association between ibrutinib start and HLH.

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The patient had concomitant EBV reactivation, a known possible trigger of HLH.

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The effect of ibrutinib on NK and T-cell was a possible contributing factor to the onset of HLH.

Anti-cytokine therapy for prevention of atherosclerosis

BACKGROUND

Currently a chronic inflammation is considered to be the one of the most important reasons of the atherosclerosis progression. A huge amount of researches over the past few decades are devoted to study the various mechanisms of inflammation in the development of atherosclerotic lesions.

PURPOSE

To review current capabilities of anti-inflammatory therapy for the prevention and treatment of atherosclerosis and its clinical manifestations.

METHODS

Appropriate articles on inflammatory cytokines in atherosclerosis and anti-inflammatory prevention of atherosclerosis were searched in PubMed Database from their respective inceptions until October 2015.

SECTIONS

"The role of inflammatory cytokines in the development of atherosclerotic lesions" describes available data on the possible inflammatory mechanisms of the atherogenesis with a special attention to the role of cytokines. "Modern experience of anti-inflammatory therapy for the treatment of atherosclerosis" describes modern anti-inflammatory preparations with anti-atherosclerotic effect including natural preparations. In "the development of anti-inflammatory herbal preparation for atherosclerosis prevention" an algorithm is demonstrated that includes screening of anti-cytokine activity of different natural products, the development of the most effective combination and estimation of its effect in cell culture model, in animal model of the acute aseptic inflammation and in a pilot clinical trial. A natural preparation "Inflaminat" based on black elder berries (Sambucus nigra L.), violet tricolor herb (Viola tricolor L.) and calendula flowers (Calendula officinalis L.) possessing anti-cytokine activity was developed using the designed algorithm. The results of the following 2-year double blind placebo-controlled clinical study show that "Inflaminat" reduces carotid IMT progression, i.e. has anti-atherosclerotic effect.

CONCLUSION

Anti-cytokine therapy may be a promising direction in moderation of atherogenesis, especially when it begins on the early stages of subclinical atherosclerosis. The use of herbal preparations with anti-cytokine mechanism of action is the most perspective for timely prevention of atherosclerosis, as they have no significant side effects and can be prescribed for long-term administration.

Making anti-cytokine therapy more selective: Studies in mice

Cytokines are involved in a wide range of functions shaping the normal immune response, yet inflammatory changes in the immune system due to dysregulated cytokine signaling may lead to the induction of autoimmunity. Cytokine inhibitors have revolutionized the treatment of many autoimmune diseases in recent years. Systemic cytokine ablation, however, is often associated with the development of adverse side effects and some patients simply do not respond to therapy. TNF, IL-1 and IL-6 are the best characterized proinflammatory cytokines considered as the main therapeutic targets for the treatment of several autoimmune and inflammatory diseases. But can anti-cytokine therapy become more selective and thus more efficient? This mini-review discusses several recently emerging paradigms and summarizes current experimental attempts to validate them in mouse studies.