Comparison of ELISA with automated ECLIA for IL-6 determination in COVID-19 patients: An Italian real-life experience.

Objectives: Coronavirus disease 2019 (COVID-19) has a wide spectrum of clinical severity. A cytokine storm is associated with COVID-19 severity. Of these, IL-6 is significantly associated with higher mortality and is also a marker for predicting disease prognosis. IL-6 may act as a target for therapeutics and, a blockade of IL-6 function by Tocilizumab has been described as a treatment of the inflammatory process COVID-19-related. This study aims to describe our experience comparing two different methods, in detail Human IL-6 Instant ELISA and the Elecsys IL-6 based on ECLIA, for the IL-6 assessment. Design and methods: IL-6 levels from serum samples of 104 COVID-19 patients, admitted to the AOU Careggi (Hospital in Florence -Italy), were assessed by using the two above-mentioned methods, and the results were analysed through Passing-Bablok regression fit and Bland-Altman plot. Results: The regression exhibited a linear relation between the methods with a regression equation (y = - 0.13 + 0.63 x; 95 % C.I. intercept = - 0.13 to 4.55; 95 % C.I. slope = 1.03 to 1.26 with R2 = 0.89, p > 0.05), showing a positive slope. The agreement of the two methods reported a bias of -25.0 pg/mL. Thus, the two methods correlate but do not agree in terms of numeric results. Conclusions: The two assays showed good comparability. However, because of the extremely wide linear range of the ECLIA, its throughput and its capacity for immune profiling, it represents an interesting emerging technology in the immunology field.

Sampling from Extracorporeal Circuit: A Step Forward for Dose Monitoring in Continuous Renal Replacement Therapy.

INTRODUCTION: Continuous renal replacement therapies (CRRTs) require constant monitoring and periodic treatment readjustments, being applied to highly complex patients, with rapidly changing clinical needs. To promote precision medicine in the field of renal replacement therapy and encourage dynamic prescription, the Acute Dialysis Quality Initiative (ADQI) recommends periodically measuring the solutes extracorporeal clearance with the aim of assessing the current treatment delivery and the gap from the therapeutic prescription (often intended as effluent dose). To perform this procedure, it is therefore necessary to obtain blood and effluent samples from the extracorporeal circuit to measure the concentrations of a target solute (usually represented by urea) in prefilter, postfilter, and effluent lines. However, samples must be collected simultaneously from the extracorporeal circuit ports, with the same suction flow at an unknown rate. METHODS: The proposed study takes the first step toward identifying the technical factors that should be considered in determining the optimal suction rate to collect samples from the extracorporeal circuit to measure the extracorporeal clearance for a specific solute. RESULTS: The results obtained identify the low suction rate (i.e., 1 mL/min) as an ideal parameter for an adequate sampling method. Low velocities do not perturb the external circulation system and ensure stability prevailing pressures in the circuit. Higher velocities can be performed only with blood flows above 120 mL/min preferably in conditions of appropriate filtration fraction. DISCUSSION/CONCLUSIONS: The specific value of aspiration flow rate must be proportioned to the prescription of CRRT treatments set by the clinician.

High proportion of inflammatory CD62Llow eosinophils in blood and nasal polyps of severe asthma patients.

BACKGROUND: In mice models, eosinophils have been divided into different subpopulations with distinct phenotypes and functions, based on CD62L and CD101 patterns of membrane expression. Limited data are available in humans. OBJECTIVE: To investigate eosinophils subpopulations in peripheral blood (PB) and nasal polyp tissue (NP) from severe eosinophilic asthma (SEA) patients plus concomitant chronic rhinosinusitis with nasal polyps (CRSwNP). METHODS: We recruited 23 SEA patients (14 with CRSwNP); as controls, we enrolled 15 non-severe asthma patients, 15 allergic rhinitis patients without asthma and 15 healthy donors. Eosinophils were isolated from PB and NP and analysed by FACS. Eotaxin-3 and eotaxin-1 mRNA expression in NP tissue was also evaluated. RESULTS: A significantly higher percentage of circulating CD62Llow cells was observed in SEA, as compared with controls, expressing higher levels of CCR3, CD69 and lower levels of CD125 (IL-5R), CRTH2, CD86 and CD28 in comparison with CD62Lbright cells. In NP, eosinophils showed a high proportion of CD62Llow phenotype, significantly greater than that observed in PB. Surface expression of IL-3R, IL-5R, CD69 and CD86 was significantly higher in CD62Llow eosinophils from NP than in those from blood. Moreover, eotaxin-3 mRNA expression positively correlated with the percentage of CD62Llow cells in NP. CONCLUSION: Two different eosinophil subphenotypes can be identified in blood and NP of SEA patients, with a preferential accumulation of CD62Llow inflammatory cells in NP.

The anti-IgE monoclonal antibody omalizumab as adjuvant treatment in desensitization to carboplatin in patients with ovarian cancer.

•Ovarian cancer is the most lethal among gynecological cancers.•Carboplatin-based chemotherapy identifies as the main systemic treatment for ovarian cancer patients.•Almost one every three patients treated with carboplatin experiences hypersensitivity reactions.•Patients may experience breakthrough reactions during drug desensitization.•Omalizumab represents a promising new treatment to overcome carboplatin hypersensitivity.

How to Prevent and Mitigate Hypersensitivity Reactions to Biologicals Induced by Anti-Drug Antibodies?

Biologicals are widely used therapeutic agents for rheumatologic diseases, cancers, and other chronic inflammatory diseases. They are characterized by complex structures and content of variable amounts of foreign regions, which may lead to anti-drug antibodies (ADA) development. ADA onset may limit the clinical usage of biologicals because they may decrease their safety. In fact they are mainly associated with immediate hypersensitivity reactions (HSRs). Development of ADAs is reduced by concomitant immunosuppressive treatment, while it is increased by longer intervals between drug administrations; thus, regular infusion regimens should be preferred to reduce HSRs. Once ADAs have formed, some procedures can be implemented to reduce the risk of HSRs. ADAs may belong to different isotype; the detection of IgE ADA is advisable to be assessed when high and early ADAs are detected, in order to reduce the risk of severe HRs. In patients who need to reintroduce the biological culprit, as alternative therapies are not available, drug desensitization (DD) may be applied. Desensitization should be conceptually dedicated to patients with an IgE-mediated HSR; however, it can be performed also in patients who had developed non-IgE-mediated HSRs. Although the underlying mechanisms behind successful DD has not been fully clarified, the DD procedure is associated with the inhibition of mast cell degranulation and cytokine production. Additionally, some data are emerging about the inhibition of drug-specific immune responses during DD.

Strategies Targeting Type 2 Inflammation: From Monoclonal Antibodies to JAK-Inhibitors.

Bronchial asthma and its frequent comorbidity chronic rhinosinusitis (CRS), are characterized by an inflammatory process at lower and upper respiratory tract, with a variability in terms of clinical presentations (phenotypes) and distinct underpin pathophysiological mechanisms (endotypes). Based on the characteristics of inflammation, bronchial asthma can be distinguished into type 2 (eosinophilic) or nontype 2 (noneosinophilic) endotypes. In type 2 asthma endotype, the pathogenic mechanism is sustained by an inflammatory process driven by Th2 cells, type 2 innate lymphoid cells (ILC2) and type 2 cytokines, which include interleukin (IL)-4, IL-5, IL-9 and IL-13. The definition of asthma and chronic rhinusinusitis phenotype/endotype is crucial, taking into account the availability of novel biologic agents, such as monoclonal antibodies targeting the classical type 2 cytokines. Recently, new therapeutic strategies have been proposed and analyzed in preliminary clinical trials. Among them Janus kinase (JAK) inhibitors, now largely used for the treatment of other chronic inflammatory diseases such as rheumatoid arthritis and inflammatory bowel diseases, is receiving great relevance. The rationale of this strategy derives from the data that JAK is a tyrosine kinase involved in the signaling of T cell receptor and of several cytokines that play a role in allergic respiratory disease, such as IL-2, IL-4 and IL-9. In this review, we discuss whether treatment with biological agents and JAK inhibitors may be equally effective in controlling type 2 inflammatory process in both asthma and CRS.

Drug-specific Treg cells are induced during desensitization procedure for rituximab and tocilizumab in patients with anaphylaxis.

Biologic agents (BA) are able to induce an adaptive immune response in a proportion of exposed patients with the onset of anti-drug antibodies (ADA), which are usually responsible for hypersensitivity reactions (HR). Drug desensitization (DD) for BA allows transient clinical tolerance to the drug in reactive patients. The paper aimed to analyse the modification of drug-specific immune responses along DD in two patients with previous ADA-mediated HR (anaphylaxis) to rituximab and tocilizumab. The in vivo and in vitro assays of humoral and cellular response to drugs were carried out in a longitudinal manner throughout the DD cycles. We observed a progressive decrease of the pre-procedure ADA titer with negativization during the DD cycles in both patients. The monitoring of the drug-specific effector cell response showed the decrease in the BA-induced proliferation, while T cell response to unrelated antigens resulted unmodified along the DD cycles. Lastly, the increase of circulating drug-specific Treg cells mainly producing IL-35 were shown during the DD treatment. This study provides evidence that DD treatment to two BA inhibits humoral and cellular anti-drug response by increasing regulatory T cells and cytokines in an antigen-restricted manner. These modifications could contribute to the safety of the procedure.

Asthma and Chronic Rhinosinusitis: How Similar Are They in Pathogenesis and Treatment Responses?

Severe asthma and rhinosinusitis represent frequent comorbidities, complicating the overall management of the disease. Both asthma and chronic rhinosinusitis (CRS) can be differentiated into endotypes: those with type 2 eosinophilic inflammation and those with a non-type 2 inflammation. A correct definition of phenotype/endotype for these diseases is crucial, taking into account the availability of novel biological therapies. Even though patients suffering from type 2 severe asthma-with or without CRS with nasal polyps-significantly benefit from treatment with biologics, the existence of different levels of patient response has been clearly demonstrated. In fact, in clinical practice, it is a common experience that patients reach a good clinical response for asthma symptoms, but not for CRS. At first glance, a reason for this could be that although asthma and CRS can coexist in the same patient, they can manifest with different degrees of severity; therefore, efficacy may not be equally achieved. Many questions regarding responders and nonresponders, predictors of response, and residual disease after blocking type 2 pathways are still unanswered. In this review, we discuss whether treatment with biological agents is equally effective in controlling both asthma and sinonasal symptoms in patients in which asthma and chronic rhinosinusitis with nasal polyps coexist.

Immunogenicity-unwanted immune responses to biological drugs - can we predict them?

INTRODUCTION: Biological agents (BAs) target molecules involved in disease mechanisms and have modified the natural history of several immune-mediated disorders. All BAs are immunogenic, resulting in the formation of antidrug antibodies (ADAs), which can neutralize drug activity leading to loss of response and potential relapse, or serious adverse events such as infusion hypersensitivity reactions. The production of ADAs is the result of a specific adaptive immune response in which T and B cells are involved. AREAS COVERED: Factors conditioning the immunogenicity of BAs, including drug-, treatment- and patient-related factors are currently the subject of many studies. Among them, a lot of attention is dedicated to define the impact of BAs structure, the effect of targeting (soluble or membrane) molecules, the impact of interruption of therapy as well as the role of genetic (HLA and non-HLA) predisposing factors and disease activity. EXPERT OPINION: Knowledge of factors capable of influencing the immunogenicity of BAs may help to understand, in a predictive manner and at the single patient level, the presence of risk factors influencing the production of ADAs and their impact on clinical outcomes.

Low-Dose Mepolizumab Effectiveness in Patients Suffering From Eosinophilic Granulomatosis With Polyangiitis.

Eosinophilic granulomatosis with polyangiitis (EGPA) is a vasculitis characterized by multisystemic manifestations including asthma. Mepolizumab (300 mg/4 weeks) has recently been approved for EGPA. However, real-life data are scarce and report experiences with high doses of mepolizumab intravenously administered (750 mg/4 weeks). The aim of our study was to investigate in a real-life setting whether mepolizumab in EGPA patients at low doses would enable us 1) to control asthma symptoms, 2) to obtain oral corticosteroids (OCS) and/or immunosuppressors tapering and 3) to maintain clinical remission and avoid disease relapses. Mepolizumab (100 mg/4 weeks) was subcutaneously administered for 12 months in 18 EGPA patients with uncontrolled severe asthma. Symptoms, annual asthma exacerbation rates, OCS-sparing effects, lung function and eosinophil activation markers were monitored. The proportion of patients with clinical remission or relapse was also evaluated in month 12. A significant decrease in the annual rate of asthma exacerbations in association with significant changes in asthma control were observed. Specifically, 66.6% of the patients experienced no exacerbations during the mepolizumab treatment. Most patients (77.7%) were able to reduce the daily OCS dose by at least 50%. Four patients also stopped cyclosporine A during the study period. No EGPA relapse was observed and a large majority of the patients achieved clinical remission (94.3%). Clinical benefits were paralleled by reduction in blood eosinophils and serum levels of eosinophil activation markers. Low-dose mepolizumab showed clinically relevant benefits in exacerbation rates, asthma symptoms, OCS and immunosuppressive use in EGPA patients. These effects occurred without any EGPA relapse for extrapulmonary manifestations.

Anaphylactic reactions to biological drugs.

PURPOSE OF REVIEW: This review summarizes the current knowledge of the pathogenic mechanisms of biologics-induced anaphylaxis, and the diagnostic and prophylactic strategies in the management of potentially reactive patients, to improve the safety profile of biologics. RECENT FINDINGS: The recent knowledge on the topic highlights the involvement of both effector and regulatory mechanisms in the immune response to biological agents. In addition, the impact of biological's immunogenicity on hypersensitivity reactions has been confirmed in a wider number of studies, defining some details about the kinetics of antidrug antibodies development, specifically immunoglobulin G (IgG) and immunoglobulin E (IgE). SUMMARY: Biological agents may induce anaphylaxis, mainly through the induction of antidrug antibodies. Biologics-related infusion reactions are often clinically consistent with type I hypersensitivity, but IgG antidrug antibodies may also be involved. The immune response toward biologicals is orchestrated by both effector and regulatory T cells. In addition, nonantibody-dependent mechanisms may occur. Among clinicians persists today again a low awareness, not only of the possibility to understand the immunological mechanisms behind anaphylaxis to biologicals but also the opportunity to apply potential strategies for the management of reactive patients aimed to guarantee a safe retreatment.

Prompt Predicting of Early Clinical Deterioration of Moderate-to-Severe COVID-19 Patients: Usefulness of a Combined Score Using IL-6 in a Preliminary Study.

BACKGROUND: The early identification of patients at risk of clinical deterioration is of interest considering the timeline of COVID-19 after the onset of symptoms. OBJECTIVE: The aim of our study was to evaluate the usefulness of testing serum IL-6 and other serological and clinical biomarkers, to predict a short-term negative clinical course of patients with noncritical COVID-19. METHODS: A total of 208 patients with noncritical COVID-19 pneumonia at admission were consecutively enrolled. Clinical and laboratory findings obtained on admission were analyzed by using survival analysis and stepwise logistic regression for variable selection. Three-day worsening as outcome in a logistic model to generate a prognostic score was used. RESULTS: Clinical worsening occurred in 63 patients (16 = died; 39 = transferred to intensive care unit; 8 worsening of respiratory failure). Forty-five of them worsened within 3 days after admission. The risk of clinical worsening was progressively enhanced along with increasing quartiles of IL-6 levels. Multivariate analysis showed that IL-6 (P = .005), C-reactive protein (CRP) (P = .003), and SaO2/FiO2 (P = .014) were the best predictors for clinical deterioration in the first 3 days after admission. The combined score yielded an area under the curve = 0.88 (95% confidence interval: 0.83-0.93). A nomogram predicting the probability of 3-day worsening was generated. The score also showed good performance for 7-day and 14- or 21-day worsening and in predicting death occurring during all the follow-up. CONCLUSIONS: Combining IL-6, CRP, and SaO2/FiO2 in a score may help clinicians to identify on admission those patients with COVID-19 who are at high risk for a further 3-day clinical deterioration.

Systemic hypereosinophilic syndromes: when autoimmunity is Th2 mediated.

PURPOSE OF REVIEW: Clinical conditions associated with hypereosinophilia represent a field of particular interest, taking into account the epidemiological impact of the different primary and secondary forms. In addition to a classical Th1 response, also Th2 cells can be involved in the pathogenesis of autoimmune diseases, among them eosinophilic forms such as eosinophilic granulomatosis with polyangiitis. RECENT FINDINGS: In patients with severe asthma, recent evidence highlights the role of pathogenic autoantibodies against autologous eosinophil proteins (e.g. eosinophil peroxidase) suggest the role of autoimmune mechanisms, particularly in patients in which asthma is included in eosinophilic vasculitis with antineutrophilic autoantibody positivity. Is now evident that in addition to Th2 cells, also type 2 innate lymphoid cells and Th1/Th17 cells play a central role in the pathogenesis of hypereosinophilic syndrome. SUMMARY: The definition of cellular and molecular mechanisms and the critical role of specific cytokines involved in the pathogenesis of hypereosinophilic syndrome open the way to new therapeutic strategies by using biological agents targeting these specific factors.

Mechanisms of Drug Desensitization: Not Only Mast Cells.

Drug desensitization (DD) allows transient clinical tolerance to the drug in reactive patients and it is frequently and successfully used in the management of both IgE and non IgE-mediated hypersensitivity reactions (HRs). The underlying mechanisms behind this process is not well understood. The desensitization procedure is associated with the inhibition of mast cells degranulation and cytokine production, that, is attributable, at least partially, to the abrogation of Ca2+ mobilization; in vitro findings and in vivo mouse models of rapid desensitization show that the organization and spatial distribution of actin is critical for Ca2+ mobilization. Some clinical observations may suggest the induction of a longer memory of tolerance by DD and they raise the suspicion that other cells and mechanisms are involved in DD. Some data are emerging about the modifications of immune responses during DD in patients with previous immediate HRs. In particular, an increase of regulatory cytokines, mainly represented by IL-10, has been shown, and more importantly, the appearance of IL-35 producing T regulatory cells has been described during DD. The release of controlled cellular mediators by mast cells over time and the development of the antigen-specific regulation of adaptive response allow to safely and successfully reach the target dose of a first line drug during DD.

Hypersensitivity reactions to biologics used in rheumatology.

Introduction: Biological agents (BAs) target disease mechanisms and have modified the natural history of several immune-mediated disorders. All BAs are immunogenic, resulting in the formation of antidrug antibodies (ADAs), which can neutralize drug activity leading to loss of response and potential relapse. In addition, ADAs can also cause serious adverse events such as infusion hypersensitivity reactions (HRs).Areas covered: This review discusses the recent knowledge on the effector and regulatory mechanisms involved in the immune response to BAs used in patients suffering from rheumatic diseases leading to the production of ADAs and the impact on clinical outcome. Specifically, the demonstration of the involvement of specific T cell responses underlines B cells activation, and ADAs production is discussed correlating them to the different possible clinical consequences.Expert opinion: Although the mechanisms of the immune response and specifically the ADAs production to BAs have been extensively clarified in the last years, as well as their capacity to impact on clinical outcomes, among clinicians today a low awareness and in some cases a rejection persists, not only of the analysis and understanding of the immunological mechanisms behind the immunogenicity of BAs, but also the possible clinical impact that this may have.

Rapid clinical improvement of atopic dermatitis in an Omalizumab treated patient.

BACKGROUND: Atopic dermatitis is a chronic inflammatory skin disorder, whose symptoms and severity grossly depend on individual trigger factors. The majority of patients are satisfactorily treated with emollients together with topical and systemic therapies. However, treatment failure or long-term side effects with conventional treatment options can be a significant clinical problem. Recently, novel therapeutic approaches focus on targeting skewed immune responses providing a more effective, and less harmful approach. Among them, variable success has been reported using Omalizumab, when used in combination with classic therapies. This report describes an interesting case of severe adult onset difficult-to-treat atopic dermatitis dramatically improved in response to treatment with Omalizumab. CASE PRESENTATION: We present a case of an adult male with severe allergic atopic dermatitis, with concomitant involvement of the face, neckline, trunk and forearms and systemic symptoms such as diarrhoea with important decrease of his daily quality of life. The patient had been prescribed oral steroids in addition to anti-histamines to no avail. Due to lack of response to classic therapies, strict diet, as well as to treatment with intravenous corticosteroids, an off-label treatment with Omalizumab based on patient weight and total IgE value was proposed. Clear clinical results were observed after only a few weeks with regards to systemic symptoms, and just after 2 months of treatment in regards to skin involvement. CONCLUSIONS: In the majority of treated patients the clinical improvement of cutaneous manifestations is expected after several months of treatment, as skin manifestations are the consequence of a chronic inflammatory process. The outstanding rapid response observed in this case as well as the persistence of the clinical remission suggests that the block of the IgE pathways modulate functions of cells involved in the pathogenic mechanisms of chronic skin inflammation but also in the acute phases observed in the flare-ups of the disease.

Efficacy and Safety of Mepolizumab (Anti-Interleukin-5) Treatment in Gleich's Syndrome.

Gleich's syndrome (GS) is characterized by recurrent episodes of angioedema, increase in body weight, fever, hypereosinophilia, and elevated serum IgM. The exact etiology remains unclear. Currently, the only treatment strategy is the administration of high dose of steroids during the acute phases. We report the case of a 37-year-old man suffering from GS with recurrent episodes of angioedema, fever, hypereosinophilia [6,000/mm3 (45%)], and high eosinophil cationic protein (ECP) (>200 µg/l), treated with oral steroids during the acute phase (prednisone 50-75 mg/day), the dose of maintenance being 25 mg/day. No monoclonal components were identified, and genetic tests exclude mutations including Bcr/Abl, JAK2 V617F, c-KIT D816V, and FIP1L1-PDGFRA. Using Luminex technology, we observed higher serum levels of interleukin (IL)-5, CCL2, and CCL11 during the acute exacerbations in comparison with the clinical remission phases though CCL11 did not achieve statistical significance. The flow-cytometric analysis identified a CD3+ CD8- lymphocyte population with high frequency of IL-4-, IL-5-, and IL-13-producing cells. No clinical benefit was observed after therapeutic strategies with imatinib, interferon-α, cyclosporine-A, and azathioprine. Due to high IL-5 serum levels, an intravenous treatment with anti-IL-5 monoclonal antibody mepolizumab (750 mg every 4 weeks) was started. A reduction in the rate of exacerbation phases/year (10 ± 3 vs 2 ± 1; p < 0.005), in the eosinophils count both in percentage (28.8 ± 12.8 vs 9.8 ± 3.9; p < 0.001) and absolute value (2,737 ± 1,946 vs 782 ± 333; p < 0.001) were observed as well as the ECP serum levels (132.7 ± 62.7 vs 21 ± 14.2 µg/l; p < 0.05). The daily dose of prednisone was significantly reduced (25 vs 7.5 mg). Any adverse effects were recorded. To the best of our knowledge, this case is the first report of the disease successfully treated with mepolizumab, and it could represent a novel therapeutic strategy in GS.