Tocilizumab for the treatment of rheumatoid arthritis and other systemic autoimmune diseases: current perspectives and future directions

Cell-Based Therapeutic Strategies for Autoimmune Diseases

Currently, the management of autoimmune disorders still being a challenge in terms of safety, efficiency, and specificity. Cell-based therapeutic strategies have emerged as a novel approach for autoimmune disease treatment, employing different cell therapy platforms, including tolerogenic dendritic cells, regulatory T cells, conventional and regulatory chimeric antigen receptor-T cells, mesenchymal and hematopoietic stem cells, each with their biological features. Here, we discuss the different cell therapy platforms, their immunological mechanisms of action, their therapeutic potential and benefits in autoimmune diseases, and challenges related to their production, scaling up, risks, and patient safety.

Plasticity of BioPhi-driven humanness optimization in ScFv-CD99 binding affinity validated through AlphaFold, HADDOCK, and MD simulations

BioPhi-guided humanization was utilized to enhance the humanness of a humanized single-chain variable fragment targeting CD99, leading to the development of two variants: HuScFvMT99/3BP and HuScFvMT99/3HY. The HuScFvMT99/3BP variant incorporated framework region modifications, leading to modest improvements in humanness, particularly in the VH domain, although the VL domain remained suboptimal. To address this limitation, HuScFvMT99/3HY was designed by combining the VL domain of wild-type with the VH domain of HuScFvMT99/3BP. Molecular dynamics simulations employing AlphaFold2, AlphaFold3, and HADDOCK were performed to evaluate the HuScFv-CD99 peptide complexes. AF2-based simulations demonstrated enhanced binding free energy (ΔGbinding) for both variants compared to HuScFvMT99/3WT. However, ΔGbinding values obtained from AF3 and HD simulations were inconsistent, with HuScFvMT99/3BP exhibiting the weakest binding affinity. While ΔGbinding patterns derived from AlphaFold3 and HADDOCK simulations aligned, amino acid decomposition analysis revealed variations in the interaction coordinates of the predicted complexes. Root-mean-square deviation analysis indicated improved structural stability for HuScFvMT99/3BP (0.975 Å) and HuScFvMT99/3HY (1.075 Å) relative to HuScFvMT99/3WT (1.225 Å). Biolayer interferometry further confirmed that HuScFvMT99/3WT exhibited the highest binding affinity (KD = 1.35 × 10⁻⁷ M) compared to HuScFvMT99/3BP (KD = 2.64 × 10⁻⁷ M) and HuScFvMT99/3HY (KD = 3.95 × 10⁻⁷ M). Supporting evidence was provided by ELISA and flow cytometry experiments. PITHA analysis revealed a high immunogenicity risk for all variants, despite HuScFvMT99/3HY displaying improved humanness, a larger complementarity-determining region (CDR) cavity, and a more hydrophobic CDR-H3 loop. These findings highlight the delicate balance between enhancing humanness and preserving the structural and functional integrity critical for therapeutic antibody development.

Brain white matter damage biomarkers

White matter (WM), constituting nearly half of the human brain's mass, is pivotal for the rapid transmission of neural signals across different brain regions, significantly influencing cognitive processes like learning, memory, and problem-solving. The integrity of WM is essential for brain function, and its damage, which can occur due to conditions such as multiple sclerosis (MS), stroke, and traumatic brain injury, results in severe neurological deficits and cognitive decline. The primary objective of this book chapter is to discuss the clinical significance of fluid biomarkers in assessing WM damage within the central nervous system (CNS). It explores the biological underpinnings and pathological changes in WM due to various neurological conditions and details how alterations can be detected and quantified through fluid biomarkers. By examining biomarkers like Myelin Basic Protein (MBP), Neurofilament light chain (NFL), and others, the chapter highlights their role in enhancing diagnostic precision, monitoring disease progression, and guiding therapeutic interventions, thus providing crucial insights into maintaining WM integrity and preventing cognitive and physical disabilities.

Immunological landscape of solid cancer: Interplay between tumor and autoimmunity

The immune system, a central player in maintaining homeostasis, emerges as a pivotal factor in the pathogenesis and progression of two seemingly disparate yet interconnected categories of diseases: autoimmunity and cancer. This chapter delves into the intricate and multifaceted role of the immune system, particularly T cells, in orchestrating responses that govern the delicate balance between immune surveillance and self-tolerance. T cells, pivotal immune system components, play a central role in both diseases. In autoimmunity, aberrant T cell activation drives damaging immune responses against normal tissues, while in cancer, T cells exhibit suppressed responses, allowing the growth of malignant tumors. Immune checkpoint receptors, example, initially explored in autoimmunity, now revolutionize cancer treatment via immune checkpoint blockade (ICB). Though effective in various tumors, ICB poses risks of immune-related adverse events (irAEs) akin to autoimmunity. This chapter underscores the importance of understanding tumor-associated antigens and their role in autoimmunity, immune checkpoint regulation, and their implications for both diseases. It also explores autoimmunity resulting from cancer immunotherapy and shared molecular pathways in solid tumors and autoimmune diseases, highlighting their interconnectedness at the molecular level. Additionally, it sheds light on common pathways and epigenetic features shared by autoimmunity and cancer, and the potential of repurposing drugs for therapeutic interventions. Delving deeper into these insights could unlock therapeutic strategies for both autoimmunity and cancer.

Drug repurposing for respiratory infections

Respiratory infections such as Coronavirus disease 2019 are a substantial worldwide health challenge, frequently resulting in severe sickness and death, especially in susceptible groups. Conventional drug development for respiratory infections faces obstacles such as extended timescales, substantial expenses, and the rise of resistance to current treatments. Drug repurposing is a potential method that has evolved to quickly find and reuse existing medications for treating respiratory infections. Drug repurposing utilizes medications previously approved for different purposes, providing a cost-effective and time-efficient method to tackle pressing medical needs. This chapter summarizes current progress and obstacles in repurposing medications for respiratory infections, focusing on notable examples of repurposed pharmaceuticals and their probable modes of action. The text also explores the significance of computational approaches, high-throughput screening, and preclinical investigations in identifying potential candidates for repurposing. The text delves into the significance of regulatory factors, clinical trial structure, and actual data in confirming the effectiveness and safety of repurposed medications for respiratory infections. Drug repurposing is a valuable technique for quickly increasing the range of treatments for respiratory infections, leading to better patient outcomes and decreasing the worldwide disease burden.

Decoding Behcet's Uveitis: an In-depth review of pathogenesis and therapeutic advances

Behcet's disease (BD) is a rare but globally distributed vasculitis that primarily affects populations in the Mediterranean and Asian regions. Behcet's uveitis (BU) is a common manifestation of BD, occurring in over two-thirds of the patients. BU is characterized by bilateral, chronic, recurrent, non-granulomatous uveitis in association with complications such as retinal ischemia and atrophy, optic atrophy, macular ischemia, macular edema, and further neovascular complications (vitreous hemorrhage, neovascular glaucoma). Although the etiology and pathogenesis of BU remain unclear, numerous studies reveal that genetic factors (such as HLA-B51), dysregulated immune responses of both the innate and adaptive immune systems, infections (such as streptococcus), and environmental factors (such as GDP) are all involved in its development. Innate immunity, including hyperactivity of neutrophils and γδT cells and elevated NK1/NK2 ratios, has been shown to play an essential role in this disease. Adaptive immune system disturbance, including homeostatic perturbations, Th1, Th17 overaction, and Treg cell dysfunction, is thought to be involved in BU pathogenesis. Treatment of BU requires a tailored approach based on the location, severity of inflammation, and systemic manifestations. The therapy aims to achieve rapid inflammation suppression, preservation of vision, and prevention of recurrence. Systemic corticosteroids combined with other immunosuppressive agents have been widely used to treat BU, and beneficial effects are observed in most patients. Recently, biologics have been shown to be effective in treating refractory BU cases. Novel therapeutic targets for treating BU include the LCK gene, Th17/Treg balance, JAK pathway inhibition, and cytokines such as IL-17 and RORγt. This article summarizes the recent studies on BU, especially in terms of pathogenesis, diagnostic criteria and classification, auxiliary examination, and treatment options. A better understanding of the significance of microbiome composition, genetic basis, and persistent immune mechanisms, as well as advancements in identifying new biomarkers and implementing objective quantitative detection of BU, may greatly contribute to improving the adequate management of BU patients.

Shaping the Future of Behçet's Uveitis Management: A Comprehensive Review of Efficacy, Challenges, and Prospects of Biologic Therapies

Behçet's uveitis (BU), a vision-threatening manifestation of Behçet's disease, poses substantial management challenges due to its chronic, relapsing nature and potential for vision loss. This review explores the role of biologic therapies in the treatment of BU, providing a comprehensive overview of their effectiveness, drawbacks, and future possibilities. Traditionally, management has relied heavily on corticosteroids and conventional immunosuppressants. However, their long-term use is frequently associated with systemic side effects and insufficient control of ocular inflammation. Biologic therapies, particularly TNF-alpha inhibitors like infliximab and adalimumab, have emerged as effective alternatives, offering better disease control and a more favorable safety profile. We critically evaluated these agents, noting their clinical efficacy in reducing inflammatory flares and preserving visual acuity. Despite their benefits, several issues remain. Accessibility, cost, and lack of long-term safety data limit their widespread use. Additionally, individual variability in treatment response necessitates personalized therapeutic strategies. Recent research has shown promise in addressing these challenges, with the emergence of novel biologic agents and personalized medicine approaches. In summary, biologic therapies represent a paradigm shift in BU management, contributing to better patient outcomes. Yet, there are significant challenges to be overcome. As we move forward, continued research, development of novel biologic agents, and a precision medicine approach will shape the future landscape of BU treatment.

Role of inflammation, immunity, and oxidative stress in hypertension: New insights and potential therapeutic targets

Hypertension is regarded as the most prominent risk factor for cardiovascular diseases, which have become a primary cause of death, and recent research has demonstrated that chronic inflammation is involved in the pathogenesis of hypertension. Both innate and adaptive immunity are now known to promote the elevation of blood pressure by triggering vascular inflammation and microvascular remodeling. For example, as an important part of innate immune system, classically activated macrophages (M1), neutrophils, and dendritic cells contribute to hypertension by secreting inflammatory cy3tokines. In particular, interferon-gamma (IFN-γ) and interleukin-17 (IL-17) produced by activated T lymphocytes contribute to hypertension by inducing oxidative stress injury and endothelial dysfunction. However, the regulatory T cells and alternatively activated macrophages (M2) may have a protective role in hypertension. Although inflammation is related to hypertension, the exact mechanisms are complex and unclear. The present review aims to reveal the roles of inflammation, immunity, and oxidative stress in the initiation and evolution of hypertension. We envisage that the review will strengthen public understanding of the pathophysiological mechanisms of hypertension and may provide new insights and potential therapeutic strategies for hypertension.

Genetically downregulated Interleukin-6 signalling is associated with a lower risk of frailty

BACKGROUND

numerous studies point towards a critical role of Interleukin 6 (IL-6) pathway in frailty pathogenesis yet the causal relationship between the two remains elusive.

METHODS

we selected genetic variants near the IL-6 receptor locus (IL-6R) associated with reduced C-reactive protein (CRP) levels, a downstream effector of IL-6 pathway, and we used them as genetic proxies of IL-6 signalling downregulation. We then performed a two-sample Mendelian randomisation (MR) to investigate the association with frailty status, as defined by the Frailty Index (FI) in 11,171 individuals from the Hellenic Longitudinal Investigation of Ageing and Diet (HELIAD) study. MR analysis was repeated after excluding depression or cognition-related FI items as well as following age or sex stratification. Association with frailty was also examined using an alternative instrument, weighted on s-IL-6R levels. Replication was attempted in UK Biobank dataset.

RESULTS

genetic predisposition to IL-6 signalling downregulation, weighted on CRP levels, was associated with lower risk of frailty, inserted either as categorical (odds ratio [95% confidence interval] = 0.15 [-3.39, -0.40], P = 0.013) or continuous variable (beta [se] = -0.09 [0.003], P = 0.0009). Sensitivity analyses revealed similar estimates across different MR methods with no evidence for horizontal pleiotropy or heterogeneity. Results remained robust after exclusion of depression or cognition-related FI items and following sex or age stratification. Genetically increased s-IL-6R levels were negatively correlated with frailty and this finding remained significant in a meta-analysis of UK Biobank and HELIAD cohorts.

CONCLUSION

our results support a potential causal effect of IL-6 signalling on frailty and further suggest that downregulation of IL-6 levels may reduce frailty risk.

Drug Repurposing for COVID-19: A Review and a Novel Strategy to Identify New Targets and Potential Drug Candidates

In December 2019, the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19) was first identified in the province of Wuhan, China. Since then, there have been over 400 million confirmed cases and 5.8 million deaths by COVID-19 reported worldwide. The urgent need for therapies against SARS-CoV-2 led researchers to use drug repurposing approaches. This strategy allows the reduction in risks, time, and costs associated with drug development. In many cases, a repurposed drug can enter directly to preclinical testing and clinical trials, thus accelerating the whole drug discovery process. In this work, we will give a general overview of the main developments in COVID-19 treatment, focusing on the contribution of the drug repurposing paradigm to find effective drugs against this disease. Finally, we will present our findings using a new drug repurposing strategy that identified 11 compounds that may be potentially effective against COVID-19. To our knowledge, seven of these drugs have never been tested against SARS-CoV-2 and are potential candidates for in vitro and in vivo studies to evaluate their effectiveness in COVID-19 treatment.

Infection, Inflammation and Immunity in Covid-19 Infection

The COVID-19 pandemic caused by the SARS-CoV-2 has increased the burden on healthcare system. Despite some progress in its diagnostics has been made, effective prevention and treatment are still insufficient. Since SARS-CoV-2 infections often cause systemic inflammation and multiple organ failure, the therapeutic options aimed at modulating the host immune responses to prevent subsequent systemic complications are demanding. The review provides a summary of the SARS-CoV-2 virus infection and underlines the current perception of pulmonary host’s immune response and its contributions to disease severity and systemic inflammation. Signaling pathways which have the potential to manipulate host immunity and improve clinical outcomes are also presented.

Biomaterials-Based Opportunities to Engineer the Pulmonary Host Immune Response in COVID-19

The COVID-19 pandemic caused by the global spread of the SARS-CoV-2 virus has led to a staggering number of deaths worldwide and significantly increased burden on healthcare as nations scramble to find mitigation strategies. While significant progress has been made in COVID-19 diagnostics and therapeutics, effective prevention and treatment options remain scarce. Because of the potential for the SARS-CoV-2 infections to cause systemic inflammation and multiple organ failure, it is imperative for the scientific community to evaluate therapeutic options aimed at modulating the causative host immune responses to prevent subsequent systemic complications. Harnessing decades of expertise in the use of natural and synthetic materials for biomedical applications, the biomaterials community has the potential to play an especially instrumental role in developing new strategies or repurposing existing tools to prevent or treat complications resulting from the COVID-19 pathology. Leveraging microparticle- and nanoparticle-based technology, especially in pulmonary delivery, biomaterials have demonstrated the ability to effectively modulate inflammation and may be well-suited for resolving SARS-CoV-2-induced effects. Here, we provide an overview of the SARS-CoV-2 virus infection and highlight current understanding of the host's pulmonary immune response and its contributions to disease severity and systemic inflammation. Comparing to frontline COVID-19 therapeutic options, we highlight the most significant untapped opportunities in immune engineering of the host response using biomaterials and particle technology, which have the potential to improve outcomes for COVID-19 patients, and identify areas needed for future investigations. We hope that this work will prompt preclinical and clinical investigations of promising biomaterials-based treatments to introduce new options for COVID-19 patients.

Anti-IL6-Receptor Tocilizumab in Refractory and Noninfectious Uveitic Cystoid Macular Edema: Multicenter Study of 25 Patients

PURPOSE

Cystoid macular edema (CME) is a leading cause of blindness. This study assessed the efficacy and safety of tocilizumab (TCZ) in refractory CME.

DESIGN

Retrospective case series.

METHODS

Patients with CME secondary to noninfectious uveitis who had inadequate response to corticosteroids and at least 1 conventional immunosuppressive drug, and in most cases to other biological agents, were studied. CME was defined as central retinal thickness greater than 300 μm. The primary outcome measure was macular thickness. Intraocular inflammation, best-corrected visual acuity (BCVA), and corticosteroid-sparing effect were also analyzed.

RESULTS

A total of 25 patients (mean ± standard deviation age 33.6 ± 18.9 years; 17 women) with CME were assessed. Underlying diseases associated with uveitis-related CME are juvenile idiopathic arthritis (n = 9), Behçet disease (n = 7), birdshot retinochoroidopathy (n = 4), idiopathic (n = 4), and sarcoidosis (n = 1). The ocular patterns were panuveitis (n = 9), anterior uveitis (n = 7), posterior uveitis (n = 5), and intermediate uveitis (n = 4). Most patients had CME in both eyes (n = 24). TCZ was used in monotherapy (n = 11) or combined with conventional immunosuppressive drugs. Regardless of the underlying disease, compared to baseline, a statistically significant improvement in macular thickness (415.7 ± 177.2 vs 259.1 ± 499.5 μm; P = .00009) and BCVA (0.39 ± 0.31 vs 0.54 ± 0.33; P = .0002) was obtained, allowing us to reduce the daily dose of prednisone (15.9 ± 13.6 mg/day vs 3.1 ± 2.3 mg/day; P = .002) after 12 months of therapy. Remission was achieved in 14 patients. Only minor side effects were observed after a mean follow-up of 12.7 ± 8.34 months.

CONCLUSION

Macular thickness is reduced following administration of TCZ in refractory uveitis-related CME.

Tocilizumab in giant cell arteritis. Observational, open-label multicenter study of 134 patients in clinical practice

OBJECTIVE

Tocilizumab (TCZ) has shown efficacy in clinical trials on giant cell arteritis (GCA). Real-world data are scarce. Our objective was to assess efficacy and safety of TCZ in unselected patients with GCA in clinical practice Methods: Observational, open-label multicenter study from 40 national referral centers of GCA patients treated with TCZ due to inefficacy or adverse events of previous therapy. Outcomes variables were improvement of clinical features, acute phase reactants, glucocorticoid-sparing effect, prolonged remission and relapses. A comparative study was performed: (a) TCZ route (SC vs. IV); (b) GCA duration (≤6 vs. >6 months); (c) serious infections (with or without); (d) ≤15 vs. >15 mg/day at TCZ onset.

RESULTS

134 patients; mean age, 73.0 ± 8.8 years. TCZ was started after a median [IQR] time from GCA diagnosis of 13.5 [5.0-33.5] months. Ninety-eight (73.1%) patients had received immunosuppressive agents. After 1 month of TCZ 93.9% experienced clinical improvement. Reduction of CRP from 1.7 [0.4-3.2] to 0.11 [0.05-0.5] mg/dL (p < 0.0001), ESR from 33 [14.5-61] to 6 [2-12] mm/1st hour (p < 0.0001) and decrease in patients with anemia from 16.4% to 3.8% (p < 0.0001) were observed. Regardless of administration route or disease duration, clinical improvement leading to remission at 6, 12, 18, 24 months was observed in 55.5%, 70.4%, 69.2% and 90% of patients. Most relevant adverse side-effect was serious infections (10.6/100 patients-year), associated with higher doses of prednisone during the first three months of therapy.

CONCLUSION

In clinical practice, TCZ yields a rapid and maintained improvement of refractory GCA. Serious infections appear to be higher than in clinical trials.

Anti-interleukin 6 receptor tocilizumab in refractory uveitis associated with Behçet's disease: multicentre retrospective study

Objective

To assess the efficacy of tocilizumab (TCZ) in refractory uveitis of Behçet's disease (BD).

Methods

Multicentre study of patients with BD-associated uveitis. Patients were refractory to conventional and biologic immunosuppressive drugs. The main outcome measures were intraocular inflammation, macular thickness, visual acuity and corticosteroid-sparing effects.

Results

We studied 11 patients (7 men) (20 affected eyes); median age 35 years. Uveitis was bilateral in nine patients. The patterns of ocular involvement were panuveitis (n = 8, with retinal vasculitis in 4), anterior uveitis (n = 2) and posterior uveitis (n = 1). Cystoid macular oedema was present in seven patients. The clinical course was recurrent (n = 7) or chronic (n = 4). Before TCZ, patients had received systemic corticosteroids, conventional immunosuppressants and the following biologic agents: adalimumab (n = 8), infliximab (n = 4), canakimumab (n = 1), golimumab (n = 3), etanercept (n = 1). TCZ was used as monotherapy or combined with conventional immunosuppressants at 8 mg/kg/i.v./4 weeks (n = 10) or 162 mg/s.c./week (n = 1). At TCZ onset the following extraocular manifestations were present: oral and/or genital ulcers (n = 7), arthritis (n = 4), folliculitis/pseudofolliculitis (n = 4), erythema nodosum (n = 2), livedo reticularis (n = 1) and neurological involvement (n = 2). TCZ yielded rapid and maintained improvement in all ocular parameters of the patients, with complete remission in eight of them. However, this was not the case for the extraocular manifestations, since TCZ was only effective in three of them. After a mean (s.d.) follow-up of 9.5 (8.05) months, TCZ was withdrawn in two cases, due to a severe infusion reaction and arthritis impairment, respectively.

Conclusion

TCZ could be a therapeutic option in patients with BD and refractory uveitis.

NETosis may play a role in the pathogenesis of Hashimoto's thyroiditis

Neutrophil extracellular traps (NETs) are shown to play important roles in the progression or development of systemic autoimmune diseases. However, implication of NETs or NETosis in the pathogenesis of non-systemic autoimmune diseases such as Hashimoto's thyroiditis (HT), a chronic inflammatory organ-specific autoimmune disease, has not been previously reported. In the present study, our results demonstrate that the concentration of NET products, neutrophil elastase (NE) and proteinase 3 (PR3) in plasma, are significantly higher in the patients with HT than in healthy controls, respectively. In addition, PR3 concentration in plasma was positively associated with the titers of autoantibodies against thyroglobulin (TGAb) and thyroid peroxidase (TPOAb) in serum, respectively. Consistently, NETosis was more markedly induced in neutrophils derived from the HT patients than controls. Concomitantly, IL-6 production in the NETosis induction system in the neutrophils from the patients was significantly higher than those in controls. Moreover, serum from HT patients but not healthy controls induced more pronounced NETosis in neutrophils. Meanwhile, our immuno-fluorescence staining results showed that NETs from the HT patients contained autoantigens. These findings together indicate roles for NETs and/or NETosis in autoantibody generation as well as pathogenesis of HT. Therefore, the underlying mechanisms of NETs in the pathogenesis of HT warrant further study.

Detection of circulating natural antibodies to inflammatory cytokines in type-2 diabetes and clinical significance

Background

Inflammatory cytokines have been demonstrated to be involved in developing insulin resistance and type-2 diabetes (T2D). Natural antibodies in the circulation have protective effects on common diseases in humans. The present study was thus designed to test the hypothesis that natural antibodies against inflammatory cytokines could be associated with T2D.

Methods

An enzyme-linked immunosorbent assay (ELISA) was developed in-house to detect plasma IgG against peptide antigens derived from interleukin 1α (IL1α), IL1β, IL6, IL8 and tumor necrosis factor-α (TNF-α) in 200 patients with T2D and 220 control subjects.

Results

Binary regression showed that compared with control subjects, T2D patients had a decreased level of plasma anti-IL6 IgG (adjusted r²=0.034, p=0.0001), anti-IL8 IgG (adjusted r²=0.021, p=0.002) and anti-TNF-α IgG (adjusted r²=0.017, p=0.003). Female patients mainly contributed to decreased levels of anti-IL6 IgG (adjusted r²=0.065, p=0.0008) and anti-IL8 IgG (adjusted r²=0.056, p=0.003), while male patients mainly contributed to decreased anti-TNF-α IgG levels (adjusted r²=0.024, p=0.005). ROC curve analysis revealed a sensitivity of 16.5% against specificity of 95.5% for anti-IL6 IgG assay and a sensitivity of 19.5% against specificity of 95.9% for anti-IL8 IgG assay. Glycated hemoglobin levels measured after 6-month glucose-lowering treatment appeared to be inversely correlated with plasma anti-IL1α IgG (r=-0.477, df=17, p=0.039) and anti-IL6 IgG (r=-0.519, df=17, p=0.023) although such correlation failed to survive the Bonferroni correction.

Conclusions

Deficiency of natural IgG against inflammatory cytokines is likely to be a risk factor for T2D development and detection of such antibodies may be useful for personalized treatment of the disease.

Electronic supplementary material

The online version of this article (10.1186/s12950-017-0171-6) contains supplementary material, which is available to authorized users.

The in vitro and in vivo anti-inflammatory activities of alphitonin-4-O-β-D-glucopyranoside

The anti-inflammatory compound, alphitonin-4-O-β-D-glucopyranoside (1), has previously been isolated in the leaves of Artokapus tonkinensis and synthesised from taxifolin. This study aimed to investigate the inhibitory effect of this compound on inflammatory cytokines, including tumour necrosis factor-alpha (TNF-α), interleukin (IL)-1, IL-6 and IL-10, in RAW264.7 macrophages and in an arthritis animal model. Compound 1 dose-dependently decreased the production of TNF-α, IL-1 and IL-6 in lipopolysaccharide-stimulated RAW264.7 cells. In contrast, the level of anti-inflammatory IL-10 increased. In a collagen antibody-induced arthritis BALB/c mouse model, compound 1 at a dose of 125 and 250 mg/kg body weight significantly decreased arthritis incidence in comparison with dexamethasone.

Affibody molecules as engineered protein drugs

Affibody molecules can be used as tools for molecular recognition in diagnostic and therapeutic applications. There are several preclinical studies reported on diagnostic and therapeutic use of this molecular class of alternative scaffolds, and early clinical evidence is now beginning to accumulate that suggests the Affibody molecules to be efficacious and safe in man. The small size and ease of engineering make Affibody molecules suitable for use in multispecific constructs where AffiMabs is one such that offers the option to potentiate antibodies for use in complex disease.

Biologics-induced interstitial lung diseases in rheumatic patients: facts and controversies

INTRODUCTION

Interstitial lung disease (ILD) is a common, devastating pulmonary complication. An increased number of reports suggesting that biological disease modifying antirheumatic drugs (DMARDs) induced or exacerbated ILDs in rheumatoid arthritis (RA) patients has garnered increased attention. Areas covered: This article discusses ILDs induced by or exacerbated during biological therapy in RA patients. The article summarizes the efficacy and safety of a variety of licensed and off-label biologics clinically used for rheumatic diseases, focusing on the onset or exacerbation of RA-associated ILDs (RA-ILDs) in RA patients treated with biologics targeting tumor necrosis factor, CD20, interleukin 1 (IL-1) and IL-6 receptors. Additionally, the pathogenesis of RA-ILDs is discussed. Expert opinion: To some extent, the possibility of biologic-induced RA-ILDs increases the difficulty in choosing an optimal regimen for RA treatment with biological agents, as the relationship between biological therapy safety and the induction or exacerbation of RA-ILDs has not been established. A framework to assess baseline disease severity, particularly standardizing the evaluation of the pulmonary condition stage in RA patients and monitoring the outcome during the biological therapy treatment, is highly needed and may substantially help guide treatment decisions and predict the treatment benefits.

Structural Mimicry of Receptor Interaction by Antagonistic Interleukin-6 (IL-6) Antibodies

Interleukin 6 plays a key role in mediating inflammatory reactions in autoimmune diseases and cancer, where it is also involved in metastasis and tissue invasion. Neutralizing antibodies against IL-6 and its receptor have been approved for therapeutic intervention or are in advanced stages of clinical development. Here we describe the crystal structures of the complexes of IL-6 with two Fabs derived from conventional camelid antibodies that antagonize the interaction between the cytokine and its receptor. The x-ray structures of these complexes provide insights into the mechanism of neutralization by the two antibodies and explain the very high potency of one of the antibodies. It effectively competes for binding to the cytokine with IL-6 receptor (IL-6R) by using side chains of two CDR residues filling the site I cavities of IL-6, thus mimicking the interactions of Phe²²⁹ and Phe²⁷⁹ of IL-6R. In the first antibody, a HCDR3 tryptophan binds similarly to hot spot residue Phe²⁷⁹. Mutation of this HCDR3 Trp residue into any other residue except Tyr or Phe significantly weakens binding of the antibody to IL-6, as was also observed for IL-6R mutants of Phe²⁷⁹. In the second antibody, the side chain of HCDR3 valine ties into site I like IL-6R Phe²⁷⁹, whereas a LCDR1 tyrosine side chain occupies a second cavity within site I and mimics the interactions of IL-6R Phe²²⁹.

Inflammation, immunity, and hypertensive end-organ damage

For >50 years, it has been recognized that immunity contributes to hypertension. Recent data have defined an important role of T cells and various T cell-derived cytokines in several models of experimental hypertension. These studies have shown that stimuli like angiotensin II, deoxycorticosterone acetate-salt, and excessive catecholamines lead to formation of effector like T cells that infiltrate the kidney and perivascular regions of both large arteries and arterioles. There is also accumulation of monocyte/macrophages in these regions. Cytokines released from these cells, including interleukin-17, interferon-γ, tumor necrosis factorα, and interleukin-6 promote both renal and vascular dysfunction and damage, leading to enhanced sodium retention and increased systemic vascular resistance. The renal effects of these cytokines remain to be fully defined, but include enhanced formation of angiotensinogen, increased sodium reabsorption, and increased renal fibrosis. Recent experiments have defined a link between oxidative stress and immune activation in hypertension. These have shown that hypertension is associated with formation of reactive oxygen species in dendritic cells that lead to formation of gamma ketoaldehydes, or isoketals. These rapidly adduct to protein lysines and are presented by dendritic cells as neoantigens that activate T cells and promote hypertension. Thus, cells of both the innate and adaptive immune system contribute to end-organ damage and dysfunction in hypertension. Therapeutic interventions to reduce activation of these cells may prove beneficial in reducing end-organ damage and preventing consequences of hypertension, including myocardial infarction, heart failure, renal failure, and stroke.

Diagnosing and treating psoriatic arthritis: an update

Psoriatic arthritis (PsA) is an inflammatory arthritis of uncertain pathogenesis, affecting approximately one in four patients with psoriasis. Onset of psoriasis typically precedes the development of PsA. Therefore, the dermatologist is ideally positioned to recognize the early signs and symptoms of PsA for diagnosis and subsequent treatment. The role of the dermatologist in early diagnosis and treatment is essential for preventing pain and functional disabilities, as well as the joint deterioration that accompanies progressive forms of PsA. Diagnosis of PsA is a key aspect of the clinical decision process for the dermatologist, as psoriasis plus PsA requires a different therapeutic approach from that required for psoriasis alone. Furthermore, PsA is associated with an increased risk of cardiovascular comorbidities that present significant health concerns. In this review, the pathogenesis and comorbidities of PsA are discussed. In addition, screening and imaging tools that aid in the diagnosis of PsA, as well as tools used for efficacy assessment, are reviewed. Available therapies are presented, with a focus on targeted biologics and emerging treatments.

Idiopathic inflammatory myopathies

The idiopathic inflammatory myopathies (IIM) consist of rare heterogeneous autoimmune disorders that present with marked proximal and symmetric muscle weakness, except for distal and asymmetric weakness in inclusion body myositis. Despite many similarities, the IIM are fairly heterogeneous from the histopathologic and pathogenetic standpoints, and also show some clinical and treatment-response differences. The field has witnessed significant advances in our understanding of the pathophysiology and treatment of these rare disorders. This review focuses on dermatomyositis, polymyositis, and necrotizing myopathy, and examines current and promising therapies.

Discovery and characterization of olokizumab: a humanized antibody targeting interleukin-6 and neutralizing gp130-signaling

Interleukin-6 (IL-6) is a critical regulator of the immune system and has been widely implicated in autoimmune disease. Here, we describe the discovery and characterization of olokizumab, a humanized antibody to IL-6. Data from structural biology, cell biology and primate pharmacology demonstrate the therapeutic potential of targeting IL-6 at “Site 3”, blocking the interaction with the signaling co-receptor gp130.

Discovery and characterization of olokizumab: a humanized antibody targeting interleukin-6 and neutralizing gp130-signaling

Interleukin-6 (IL-6) is a critical regulator of the immune system and has been widely implicated in autoimmune disease. Here, we describe the discovery and characterization of olokizumab, a humanized antibody to IL-6. Data from structural biology, cell biology and primate pharmacology demonstrate the therapeutic potential of targeting IL-6 at "Site 3", blocking the interaction with the signaling co-receptor gp130.

Life-threatening complications of adult-onset Still's disease

Adult-onset Still's Disease (AOSD) since its description in 1971 has proven to be a very complex and challenging disease entity. This rare auto-inflammatory disease is classically described by the "Still's triad" of fever, rash, and arthritis, although the atypical cases frequently outnumber the typical ones. The exact pathogenesis and etiologic factors responsible for the clinical features remain largely obscure, despite recent suggestive cytokine biology findings. Diagnosis is made on clinical grounds, following the exclusion of mimickers of infectious, autoimmune or neoplastic etiology, with the additional consideration of non-specific laboratory abnormalities such as peripheral leukocytosis and elevation of serum ferritin and other acute phase reactants. The disease manifestations are protean and can include diverse complications, affecting multiple organ systems. Moreover, the severity of the organ involvement can vary considerably, representing a wide spectrum from the self-limited to severe. The mainstay of therapy has evolved from the traditional use of corticosteroids and oral immunosupressants to the newer targeted treatments with biologic agents. The scope of this review is to alert the clinician to the existence of life-threatening AOSD complications, namely the macrophage activation syndrome, disseminated intravascular coagulopathy, thrombotic thrombocytopenic purpura, diffuse alveolar hemorrhage, and pulmonary arterial hypertension. Such knowledge may lead in earlier recognition, prompt treatment, and, ideally, improved patient outcomes.

Targeting interleukin-6 in inflammatory autoimmune diseases and cancers

Interleukin-6 (IL-6) is a pleiotropic cytokine with significant functions in the regulation of the immune system. As a potent pro-inflammatory cytokine, IL-6 plays a pivotal role in host defense against pathogens and acute stress. However, increased or deregulated expression of IL-6 significantly contributes to the pathogenesis of various human diseases. Numerous preclinical and clinical studies have revealed the pathological roles of the IL-6 pathway in inflammation, autoimmunity, and cancer. Based on the rich body of studies on biological activities of IL-6 and its pathological roles, therapeutic strategies targeting the IL-6 pathway are in development for cancers, inflammatory and autoimmune diseases. Several anti-IL-6/IL-6 receptor monoclonal antibodies developed for targeted therapy have demonstrated promising results in both preclinical studies and clinical trials. Tocilizumab, an anti-IL-6 receptor antibody, is effective in the treatment of various autoimmune and inflammatory conditions notably rheumatoid arthritis. It is the only IL-6 pathway targeting agent approved by the regulatory agencies for clinical use. Siltuximab, an anti-IL-6 antibody, has been shown to have potential benefits treating various human cancers either as a single agent or in combination with other chemotherapy drugs. Several other anti-IL-6-based therapies are also under clinical development for various diseases. IL-6 antagonism has been shown to be a potential therapy for these disorders refractory to conventional drugs. New strategies, such as combination of IL-6 blockade with inhibition of other signaling pathways, may further improve IL-6-targeted immunotherapy of human diseases.

[Clinical and biological efficacy of tocilizumab in giant cell arteritis: report of three patients and literature review]

INTRODUCTION

Treatment of giant cell arteritis is based on prolonged corticosteroid therapy but adverse side effects are common especially in the elderly.

CASE REPORTS

We report three patients with giant cell vasculitis treated by tocilizumab, an interleukin-6 receptor antibody, owing to resistance or intolerance to corticosteroid therapy. A favorable outcome was rapidly observed both on clinical and biological data allowing a corticoid therapy sparing.

CONCLUSION

Tocilizumab is a promising treatment of giant cell arteritis but controlled trials are needed to confirm its efficacy.

Suppression of autoimmune retinal inflammation by an antiangiogenic drug

Chronic and recurrent uveitis account for approximately 10% of legal blindness in the western world. Autoimmune uveitis is driven by activated CD4⁺ T cells that differentiate into effector T helper cells (Th1, Th2, and Th17) which release proinflammatory cytokines that damage the retina. In this study we investigated the effect of the methionine aminopeptidase 2 (MetAP2) inhibitor, Lodamin, on T cell activation and differentiation. MetAp2 is an enzyme which regulates cellular protein synthesis and is highly expressed in T cells. Lodamin was found to suppress T cell receptor (TCR) mediated T cell proliferation and reduced the production of Th1 and Th17 cells. Further, Lodamin suppressed overall inflammation in the mouse model of experimental autoimmune uveitis (EAU) by a six fold. This effect was attributed in part to a reduction in retinal proinflammatory cytokines, down regulation of MetAP2 expression in purified lymph node CD4⁺ T cells, and a general normalization of the systemic immune reaction.

Current and future treatments for Behçet's uveitis: road to remission

Behçet's disease (BD) is a multisystem inflammatory disorder of uncertain origin, although it remains defined within the spectrum of systemic immune-mediated vasculitic disorders and also represents a spectrum of putative autoimmune disease. Major symptoms include oral aphthous ulcers, genital ulcerations, skin lesions, and ocular lesions. Despite afflicting many systems, ocular complications of BD are some of the more devastating for the patient and their quality of life. Eye involvement, which affects 60-80 % of BD patients, is characterized in its more severe form by posterior or panuveitis including occlusive retinal vasculitis. While pathogenesis of BD remains complex, association with Class I MHC (HLA-B*51) predisposing to inflammation with engagement of the innate-immune system (neutrophils, NK cells), and perpetuated by the adaptive T cell responses against infectious- and/or auto-antigens. Despite the choice of conventional immunosuppressive therapies available, only recently with the advent of biologic therapy has visual prognosis and outcomes been substantially and favorably altered. For example, both interferon-α (IFN-α) and tumour necrosis factor (TNF)-α antagonists deliver promising results and for the first time improve prognosis. With IFN-α therapy, durable remissions of uveitis can be achieved and lead to drug-free remission. Similarly, anti-TNF therapy with infliximab is reported to be rapidly effective in inducing and maintaining remission. Most recently, rising evidence reports on the use of adalimumab, etanercept, and golimumab, while use of anti-interleukin (IL)-1 agents (anakinra, canakinumab, gevokizumab), IL-6 blockers (tocilizumab), and rituximab (depleting anti-CD20 antibody) is also increasing. The aim of this review is to provide evidence for the role of conventional therapies combined with evidence for advantages and disadvantages of biologic therapies in the treatment of ocular BD. Although randomized controlled trials remain sparse, evidence remains strong and enticing that biologic agents are invaluable for the treatment of sight-threatening Behçet's uveitis and makes it an exciting time for Behçet's specialists worldwide.

Biologic therapy for autoimmune diseases: an update

Biologic therapies for rheumatologic diseases, which are targeted at molecules involved in the mechanisms of the immune system, provide an alternative to the existing treatment methods of disease-modifying anti-rheumatic drugs and other immunosuppressive medications. However, the current drawbacks of biologic therapies, including the inconvenience of intravenous administration, the high costs of these drugs, and the adverse events associated with them, prevent their wide use as first-line medications. This review provides an update of the recent literature on the new biologic therapies available. The review concentrates on nine drugs: tocilizumab, rituximab, ofatumumab, belimumab, epratuzumab, abatacept, golimumab, certolizumab, and sifalimumab, which are used as therapies for rheumatoid arthritis, spondyloarthritis, systemic lupus erythematosus, systemic sclerosis, or vasculitis.

Successful treatment of massive intractable pericardial effusion in a patient with systemic lupus erythematosus with tocilizumab

A 51-year-old Japanese woman developed systemic lupus erythematosus (SLE) in 1995. In August 2005, she had massive pericardial effusion due to lupus pericarditis, which was compromising her circulation. Methylprednisolone pulse, intravenous cyclophosphamide pulse and pericardiocentesis were all ineffective. The pericardium was cut surgically to create a passage to drain the liquid into the pleural cavity. The procedure was temporarily effective; however, massive liquid accumulated in the pleural cavity within 1 year. Oral tacrolimus and topical betamethasone injection were ineffective. Since the interleukin-6 (IL-6) level in the effusion was markedly increased (1160 pg/ml), tocilizumab was administered intravenously at a dose of 8 mg/kg every 4 weeks. The effect was astonishing and only a residual amount of pericardial effusion remained. Prednisolone was tapered successfully from 15 to 5 mg daily. Tocilizumab is a treatment of choice when we confront an intractable serositis with massive effusion in SLE, if the IL-6 level is high.

Cytokine inhibition as a strategy for treating systemic lupus erythematosus

Cytokines regulate and control the immune system. In systemic lupus erythematosus, several of these cytokines are overexpressed and contribute to the pathogenesis of the disease. Cytokine inhibition has been successfully used to treat other rheumatic and autoimmune diseases, and several cytokines are currently being investigated to determine whether inhibition would be therapeutic in lupus. The cytokines discussed in this review have all undergone clinical trials, and include TNF-α, IL-1, IL-6, IL-10, IL-15, IL-17, IL-18 and IL-23. Inhibition of the majority of these targets was safe and showed some efficacy in treating lupus. Cytokine inhibition strategies have just started to realize their potential for the treatment of this difficult disease, and show great promise for the future.

Interleukin-6: from an inflammatory marker to a target for inflammatory diseases

The incidence and diversity of chronic inflammatory diseases is increasing worldwide. However, the complexity of clinical symptoms has made it difficult to develop therapies that provide a substantial improvement for extended periods of time in a wide range of patient groups. Thus, there is a need for new therapies that target inflammatory responses without compromising immune defense. Interleukin (IL)-6, one of the first identified cytokines, has recently been recognized as a potential target in inflammatory disease. Here, I discuss how this cytokine has evolved from being a marker of inflammation to a successful target to control inflammation. I will summarize the results from the recent clinical studies using IL-6 receptor blockade, and describe potential mechanisms by which IL-6 can contribute to the progression of inflammatory diseases.