Anti-TNF therapy

Anti-tumor necrosis factor therapy in Bulgarian pediatric patients with inflammatory bowel disease - an 8-year experience of a referral center

INTRODUCTION

Anti-tumor necrosis factor (anti-TNF) therapy has become a mainstay in the treatment of patients with inflammatory bowel disease over the past few decades.

Pharmacogenomics on the Treatment Response in Patients with Psoriasis: An Updated Review

The efficacy and the safety of psoriasis medications have been proved in trials, but unideal responses and side effects are noted in clinical practice. Genetic predisposition is known to contribute to the pathogenesis of psoriasis. Hence, pharmacogenomics gives the hint of predictive treatment response individually. This review highlights the current pharmacogenetic and pharmacogenomic studies of medical therapy in psoriasis. HLA-Cw*06 status remains the most promising predictive treatment response in certain drugs. Numerous genetic variants (such as ABC transporter, DNMT3b, MTHFR, ANKLE1, IL-12B, IL-23R, MALT1, CDKAL1, IL17RA, IL1B, LY96, TLR2, etc.) are also found to be associated with treatment response for methotrexate, cyclosporin, acitretin, anti-TNF, anti-IL-12/23, anti-IL-17, anti-PDE4 agents, and topical therapy. Due to the high throughput sequencing technologies and the dramatic increase in sequencing cost, pharmacogenomic tests prior to treatment by whole exome sequencing or whole genome sequencing may be applied in clinical in the future. Further investigations are necessary to manifest potential genetic markers for psoriasis treatments.

The Evolution of TNF-α Blockade for the Treatment of Rheumatoid Arthritis

Tumor necrosis factor (TNF)-α is a potent trimeric cytokine which plays a fundamental role in the host immuno-inflammatory response, as well as in homeostasis and development. Although critical for canonical immune function, TNF-α has great destructive potential and is implicated in the development of multiple immune-mediated disorders. Within the context of rheumatoid arthritis (RA), TNF-α acts as a primary pathogenic driver by precipitating a pro-inflammatory cytokine cascade and coordinating the attraction and activation of immune cells, all of which culminate in damage to the synovium. The discovery of the paramount role of TNF-α in the pathophysiology of RA motivated studies to understand the effects of TNF blockade in vitro and in vivo. Promising preclinical results provided the impetus for clinical trials, spearheaded in the 1980s and 90s by Marc Feldmann, which revealed significant improvements across RA symptom scores and finally led to FDA approval in 1998. As of 2021, five TNF-α blocking agents have been widely applied clinically, including infliximab (IFX), etanercept (ETN), adalimumab (ADA), golimumab (GLM) and certolizumab pegol (CZP). All of them successfully ameliorated symptoms of RA and the associated tissue damage, especially in patients not responding to traditional treatment methods. Anti-TNFs are most often administered in combination with methotrexate (MTX) as part of Phase II treatment (i.e., second line). Although the general availability of anti-TNFs has dramatically improved patient outcomes, sustained remission is rare and the mechanism of RA remains incompletely understood. Thus, additional basic and translational research is warranted, towards the aim of developing novel RA treatments.

Disease-specific ADRs of TNF-α inhibitors as reported by patients with inflammatory rheumatic diseases: a registry-based prospective multicenter cohort study

BACKGROUND

The extent to which adverse drug reactions (ADRs) of biologics differ per immune-mediated inflammatory disease (IMID), and the relevance of tailoring ADR information per IMID is not fully investigated. We aimed to compare patient-reported ADRs attributed to adalimumab and etanercept between different inflammatory rheumatic diseases (IRDs).

RESEARCH DESIGN AND METHODS

ADR reports from IRD patients were extracted from the Dutch Biologic Monitor. ADR frequencies were compared using Fischer-Freeman-Halton exact test and the influence of covariates was assessed using binomial logistic regression.

RESULTS

A total, of 729 participants were included, of which 354 participants reported 887 unique ADRs. ADR frequencies were not significantly different between the IRDs. Rheumatoid arthritis and ankylosing spondylitis including axial spondyloarthritis patients had an increased risk of ADRs related to 'Respiratory, thoracic and mediastinal disorders' and as compared to psoriatic arthritis patients. Etanercept use, combination therapy with methotrexate and/or corticosteroids, and age also influenced the risk of reporting specific ADRs.

CONCLUSIONS

There were no differences in frequencies and nature of patient-reported ADRs attributed to adalimumab and etanercept between different IRDs. However, more research is needed to align patients' and health-care professionals' perspectives to improve knowledge on disease-specific ADRs.

Identification of Anti-TNFα VNAR Single Domain Antibodies from Whitespotted Bambooshark (Chiloscyllium plagiosum)

Tumor necrosis factor α (TNFα), an important clinical testing factor and drug target, can trigger serious autoimmune diseases and inflammation. Thus, the TNFα antibodies have great potential application in diagnostics and therapy fields. The variable binding domain of IgNAR (VNAR), the shark single domain antibody, has some excellent advantages in terms of size, solubility, and thermal and chemical stability, making them an ideal alternative to conventional antibodies. This study aims to obtain VNARs that are specific for mouse TNF (mTNF) from whitespotted bamboosharks. After immunization of whitespotted bamboosharks, the peripheral blood leukocytes (PBLs) were isolated from the sharks, then the VNAR phage display library was constructed. Through phage display panning against mTNFα, positive clones were validated through ELISA assay. The affinity of the VNAR and mTNFα was measured using ELISA and Bio-Layer Interferometry. The binding affinity of 3B11 VNAR reached 16.7 nM. Interestingly, one new type of VNAR targeting mTNF was identified that does not belong to any known VNAR type. To understand the binding mechanism of VNARs to mTNFα, the models of VNARs-mTNFα complexes were predicted by computational modeling combining HawkDock and RosettaDock. Our results showed that four VNARs’ epitopes overlapped in part with that of mTNFR. Furthermore, the ELISA assay shows that the 3B11 potently inhibited mTNFα binding to mTNFR. This study may provide the basis for the TNFα blockers and diagnostics applications.

Treatment of Cardiovascular Disease in Rheumatoid Arthritis: A Complex Challenge with Increased Atherosclerotic Risk

Rheumatoid arthritis (RA) carries significant risk for atherosclerotic cardiovascular disease (ASCVD). Traditional ASCVD risk factors fail to account for this accelerated atherosclerosis. Shared inflammatory pathways are fundamental in the pathogenesis of both diseases. Considering the impact of RA in increasing cardiovascular morbidity and mortality, the characterization of therapies encompassing both RA and ASCVD management merit high priority. Despite little progress, several drugs discussed here promote remission and or lower rheumatoid disease activity while simultaneously conferring some level of atheroprotection. Methotrexate, a widely used disease-modifying drug used in RA, is associated with significant reduction in cardiovascular adverse events. MTX promotes cholesterol efflux from macrophages, upregulates free radical scavenging and improves endothelial function. Likewise, the sulfonamide drug sulfasalazine positively impacts the lipid profile by increasing HDL-C, and its use in RA has been correlated with reduced risk of myocardial infraction. In the biologic class, inhibitors of TNF-α and IL-6 contribute to improvements in endothelial function and promote anti-atherogenic properties of HDL-C, respectively. The immunosuppressant hydroxychloroquine positively affects insulin sensitization and the lipid profile. While no individual therapy has elicited optimal atheroprotection, further investigation of combination therapies are ongoing.

MicroRNA-106b Overexpression Suppresses Synovial Inflammation and Alleviates Synovial Damage in Patients with Rheumatoid Arthritis

OBJECTIVES

To explore the effect of miR-106b on synovial inflammation and damage in rheumatoid arthritis (RA) patients, and further to investigate its possible mechanism.

METHODS

: Quantitative real-time polymerase chain reaction (qRT-PCR), immunofluorescence, in situ hybridization and immunohistochemistry assay were separately used to verify the levels of miR-106b and cytokines in the synovial tissues of patients with RA or osteoarthritis (OA). Pearson correlation analysis was conducted to examine the bivariate relationship between miR-106b and cytokines or RANKL. Following the isolation and culture of fibroblast-like synoviocytes (FLS), the cells were transfected with lentivirus-mediated miR-106b mimic, miR-106b inhibitor, and negative control miR-106b mimic, respectively. Thereafter, cell proliferation was measured by Cell Counting Kit-8 assay, and cell invasion and migration capacity was assessed by Transwell assay. Furthermore, concentration and expression of cytokines were separately detected by Enzyme linked immunosorbent assay and Western blot.

RESULTS

Compared with osteoarthritis, validation by qRT-PCR showed that RA patients had a lower level of miR-106b and higher levels of receptor activator of nuclear factor-κ B ligand (RANKL), tumor necrosis factor-a (TNF-a) and interleukin-6 (IL-6). Additionally, the scatter plot showed that the relative transcription of miR-106b level was negatively correlated to the level of TNF-a, IL-6, and RNKAL in the synovial tissues of both RA and OA patients (All P<0.05). Furthermore, miR-106b overexpression suppressed cell proliferation, migration and invasion capacity of human RA-FLS.

CONCLUSIONS

miR-106b overexpression suppresses synovial inflammation and alleviates synovial damage, thus it may be served as a potential therapeutic target for RA patients.

Targeting B cells in the pre-phase of systemic autoimmunity globally interferes with autoimmune pathology

Systemic lupus erythematosus (SLE) is characterized by a loss of self-tolerance, systemic inflammation, and multi-organ damage. While a variety of therapeutic interventions are available, it has become clear that an early diagnosis and treatment may be key to achieve long lasting therapeutic responses and to limit irreversible organ damage. Loss of humoral tolerance including the appearance of self-reactive antibodies can be detected years before the actual onset of the clinical autoimmune disease, representing a potential early point of intervention. Not much is known, however, about how and to what extent this pre-phase of disease impacts the onset and development of subsequent autoimmunity. By targeting the B cell compartment in the pre-disease phase of a spontaneous mouse model of SLE we now show, that resetting the humoral immune system during the clinically unapparent phase of the disease globally alters immune homeostasis delaying the downstream development of systemic autoimmunity.

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The clinically unapparent pre-phase of SLE impacts clinical disease

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Autoreactive IgM antibodies represent a biomarker for early therapeutic intervention

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Pre-phase B cells orchestrate clinical disease

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Depleting pre-phase B cells diminishes disease pathology

Differences and similarities in clinical and functional responses among patients receiving tofacitinib monotherapy, tofacitinib plus methotrexate, and adalimumab plus methotrexate: a post hoc analysis of data from ORAL Strategy

BACKGROUND

This post hoc analysis assessed clinical and functional responses to tofacitinib monotherapy, tofacitinib + methotrexate (MTX), and adalimumab + MTX, in patients with rheumatoid arthritis enrolled in the ORAL Strategy study, including evaluation of patient-level data using cumulative probability plots.

METHODS

In the 12-month, phase IIIb/IV ORAL Strategy study, patients with rheumatoid arthritis and an inadequate response to MTX were randomized to receive tofacitinib 5 mg twice daily (BID), tofacitinib 5 mg BID + MTX, or adalimumab 40 mg every other week + MTX. In this post hoc analysis, cumulative probability plots were generated for mean percent change from baseline (%∆) in the Clinical Disease Activity Index (CDAI; clinical response) and mean change from baseline (∆) in the Health Assessment Questionnaire-Disability Index (HAQ-DI; functional response) at month 12. Median C-reactive protein (CRP) levels by time period were summarized by CDAI remission (≤ 2.8) status at months 6 and 12.

RESULTS

Data for 1146 patients were analyzed. At month 12, cumulative probability plots for %∆CDAI and ∆HAQ-DI were similar across treatments in patients with greater response. At lower levels of response, patients receiving tofacitinib monotherapy did not respond as well as those receiving combination therapies. With tofacitinib + MTX, numerically higher baseline CRP levels and numerically larger post-baseline CRP reductions were seen in patients achieving CDAI remission at months 6 and 12 vs those who did not.

CONCLUSIONS

These results suggest that patients with a greater response did well, irrespective of which therapy they received. Patients with lesser response had better outcomes with combination therapies vs tofacitinib monotherapy, suggesting they benefitted from MTX. High pre-treatment CRP levels may be associated with better response to tofacitinib + MTX.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02187055. Registered on 08 July 2014.

Therapeutic use of specific tumour necrosis factor inhibitors in inflammatory diseases including COVID-19

Coronavirus disease 2019 (COVID-19) has caused significant devastation globally. Despite the development of several vaccines, with uncertainty around global uptake and vaccine efficacy, the need for effective therapeutic agents remains. Increased levels of cytokines including tumour necrosis factor are significant in the pathogenesis of COVID-19 and associated with poor outcomes including ventilator requirement and mortality. Repurposing tumour necrosis factor blocker therapy used in conditions such as rheumatoid arthritis and inflammatory bowel disease seems promising, with early feasibility data showing a reduction in circulation of pro-inflammatory cytokines and encouraging the evaluation of such interventions in preventing disease progression and clinical deterioration in patients with COVID-19. Here, we examine the biological activities of tumour necrosis factor inhibitors indicative of their potential in COVID-19 and briefly outline the randomised control trials assessing their benefit-risk profile in COVID-19 therapy.

Rare Complication During Anti-TNF-α Treatment in a Patient with Crohn's Disease: A Case Report and Review of the Literature

Crohn's disease represents an inflammatory bowel disease of unknown etiology, with chronic evolution, which may affect any segment of the digestive tract. The main classes of drugs used in patients with inflammatory bowel disease include: aminosalicylates, corticosteroids, immunosuppressants, biological agents and antibiotics. Biological therapy with anti-TNF-α agents offers significant therapeutic benefits, but their use requires caution, as they can also be associated with numerous side effects. We present the case of a female patient known with Crohn's disease, under going biological therapy with adalimumab, who developed a complication, quite rarely described in the literature, possibly as a result of treatment with anti-TNF-α agents.

The recombinant anti-TNF-α fusion protein ameliorates rheumatoid arthritis by the protective role of autophagy

The currently used anti-cytokine therapeutic antibodies cannot selectively neutralize pathogenic cytokine signaling that cause collateral damage to protective signaling cascades carrying the potential for unwanted side effects. The variable domains of heavy-chain only antibodies (HCAbs) discovered in Camelidae are stable and display to be fully functional in antigen-binding against variable targets, which seem to be attractive candidates for the next-generation biologic drug study. The purpose of our study was to establish a simple prokaryotic expression system for large-scale expression, purification, and refolding of the recombinant anti-tumor necrosis factor α (TNF-α) fusion protein (FVH1-1) from inclusion bodies. Over 95% purity of the recombinant anti-TNF-α fusion proteins was obtained by just one purification step in our developed prokaryotic expression system, while the results of surface plasmon resonance (SPR) established the high-efficiency potent binding ability of FVH1-1 to human TNF-α. The counteraction of TNF-α cytotoxic effect experiment on the mouse fibroblast fibrosarcoma cell line (L929) confirmed that the expressed FVH1-1 were able to selectively and highly combine with human recombinant TNF-α (hTNF-α) in vitro. Western blot results showed that FVH1-1 can inhibit the activation of caspase-9 and PARP, which are the apoptotic signaling pathway proteins activated by hTNF-α. Meanwhile, lysosome autophagy signaling pathways stimulated by hTNF-α were inhibited by FVH1-1, which down-regulated the expression of LC3II/LC3I and up-regulated the expression of P62, indicating that the autophagy linked with TNF-α-induced apoptosis in response to rheumatoid arthritis. The results of the AIA rat model experiment presented that FVH1-1 can reduce the degree of joint swelling and inflammatory factors to a certain extent in vivo.

Immunogenicity to biological drugs in psoriasis and psoriatic arthritis

Monoclonal antibodies or fusion proteins, defined as biological drugs, have modified the natural history of numerous immune-mediated disorders, allowing the development of therapies aimed at blocking the pathophysiological pathways of the disease, providing greater efficacy and safety than conventional treatment strategies. Virtually all therapeutic proteins elicit an immune response, producing anti-drug antibodies (ADAs) against hypervariable regions of immunoglobulins. Immunogenicity against biological drugs can alter their pharmacokinetic and pharmacodynamic properties, thereby reducing the efficacy of these drugs. In more severe cases, ADAs can neutralize the therapeutic effects of the drug or cause serious adverse effects, mainly hypersensitivity reactions. The prevalence of ADAs varies widely depending on the type of test used, occurrence of false-negative results, and non-specific binding to the drug, making it difficult to accurately assess their clinical impact. Concomitant use of immunosuppressors efficiently reduces the immunogenicity in a dose-dependent manner, either by decreasing the frequency of detectable ADAs or by delaying their appearance, thereby enhancing the effectiveness of biological therapies. Among the new therapeutic strategies for the management of psoriasis, biological agents have gained increasing importance in recent years as they interrupt key inflammation pathways involved in the physiopathology of the disease. Reports regarding ADA in new biologics are still scarce, but the most recent evidence tends to show little impact on the clinical response to the drug, even with prolonged treatment. It is therefore essential to standardize laboratory tests to determine the presence and titles of ADAs to establish their administration and management guidelines that allow the determination of the real clinical impact of these drugs.

Tuberculosis and Biologic Therapies: Anti-Tumor Necrosis Factor-α and Beyond

Biologic drugs have revolutionized the treatment of certain hematologic, autoimmune, and malignant diseases, but they may place patients at risk for reactivation or acquisition of tuberculosis. This risk is highest with the tumor necrosis factor-alpha (TNF-α) inhibitors. Amongst this class of drugs, the monoclonal antibodies (infliximab, adalimumab, golimumab) and antibody fragment (certolizumab) carry an increased risk compared to the soluble receptor fusion molecule, etanercept. Treatment of latent TB is critical to decrease the risk of reactivation. Data continues to emerge regarding tuberculosis risk associated with novel biologics targeting cytokines involved in tuberculosis control.

Reducing Perioperative Risks of Surgery in Crohn's Disease

BACKGROUND

Approximately one-third of all patients suffering from Crohn's disease (CD) undergo surgery within the first 10 years after diagnosis and another 20% will have a second operation in the 10 years after their first operation. Surgery will remain an essential part of managing CD and therefore it is crucial to prevent perioperative complications by optimizing perioperative management.

METHODS

We reviewed the current literature on managing immunomodulating therapy, nutritional support, and thromboembolic prophylaxis in the perioperative situation.

RESULTS

CD patients with serious nutritional deficits (weight loss >10% in the last 3-6 months, body mass index <18.5 kg/m2, or albumin levels <30 g/L) benefit from intensive enteral or parenteral nutritional support, thereby reducing the risk of surgical-site infections and post-operative septic complications. Immunosuppressive therapy with prednisolone doses >20 mg should be avoided. The risk of therapy with anti-TNFα agents, vedolizumab, and ustekinumab for surgical complications has not been fully established. Analysis of currently available data suggests that an interval of 4-8 weeks is prudent to avoid complications and reduce risk by performing protective ostomy in the emergency setting. Finally, due to the high risk of venous thromboembolism, prophylactic therapy with heparin is recommended.

CONCLUSION

As most cases of CD-related surgery are performed in a non-emergency setting, careful planning and risk management can reduce the rate of surgical complications, increase quality of life, and also reduce costs.

Characterization of Novel Fragment Antibodies Against TNF-alpha Isolated Using Phage Display Technique

Tumor necrosis factor alpha (TNF-α) is an inflammatory cytokine which plays crucial roles in pathogenesis of inflammatory diseases. The current study aimed to investigate the binding abilities of I44 and I49 domain antibodies to TNF-α. The dAbs were expressed in bacterial expression system and purified by affinity chromatography using Ni-sepharose column. The expression and purity of the proteins were evaluated using western blotting and SDS-PAGE techniques, respectively. ELISA experiment showed that I44 and I49 dAbs bind to TNF-α with the binding constants (K_d) of 5.18 ± 1.41 and 2.42 ± 0.55 µM, respectively. The inhibitory effect of dAbs on TNF-α biological effect was determined in MTT assay in which I44 and I49 prevented TNF-α cell cytotoxicity with IC₅₀ values of 6.61 and 3.64 µM, respectively. The identified anti-TNF-α dAbs could bind to and inhibit TNF-α activity. The dAbs activities can be attributed to their ability to establish hydrogen bonds as well as hydrophobic contacts with TNF-α. The results of the current study can pave the way for further structural studies in order to introduce new more potent anti-TNF-α antibodies.

Inflammation in human adipose tissues-Shades of gray, rather than white and brown

Chronic inflammation in adipose tissues has been associated with obesity and metabolic syndrome over the years. Various studies using animal models have contributed to our knowledge on the pro- and anti- inflammatory mediators that regulate obesity. Analyses of cytokine profiles in humans have not revealed a clear scenario. Likewise, treatments targeting inflammation to control obesity and insulin resistance has not yielded promising results. In this review we summarize the data available in human obesity and discuss the possible reasons that could explain the difficulties in treating obesity and insulin resistance by targeting pro-inflammatory cytokines.

Anti-Tumor Necrosis Factor α Therapeutics Differentially Affect Leishmania Infection of Human Macrophages

Tumor necrosis factor α (TNFα) drives the pathophysiology of human autoimmune diseases and consequently, neutralizing antibodies (Abs) or Ab-derived molecules directed against TNFα are essential therapeutics. As treatment with several TNFα blockers has been reported to entail a higher risk of infectious diseases such as leishmaniasis, we established an in vitro model based on Leishmania-infected human macrophages, co-cultured with autologous T-cells, for the analysis and comparison of anti-TNFα therapeutics. We demonstrate that neutralization of soluble TNFα (sTNFα) by the anti-TNFα Abs Humira^®, Remicade^®, and its biosimilar Remsima^® negatively affects infection as treatment with these agents significantly reduces Leishmania-induced T-cell proliferation and increases the number of infected macrophages. By contrast, we show that blockade of sTNFα by Cimzia^® does not affect T-cell proliferation and infection rates. Moreover, compared to Remicade^®, treatment with Cimzia^® does not impair the expression of cytolytic effector proteins in proliferating T-cells. Our data demonstrate that Cimzia^® supports parasite control through its conjugated polyethylene glycol (PEG) moiety as PEGylation of Remicade^® improves the clearance of intracellular Leishmania. This effect can be linked to complement activation, with levels of complement component C5a being increased upon treatment with Cimzia^® or a PEGylated form of Remicade^®. Taken together, we provide an in vitro model of human leishmaniasis that allows direct comparison of different anti-TNFα agents. Our results enhance the understanding of the efficacy and adverse effects of TNFα blockers and they contribute to evaluate anti-TNFα therapy for patients living in countries with a high prevalence of leishmaniasis.

10-Year Associations Between Tumor Necrosis Factor Receptors 1 and 2 and Cardiovascular Events in Patients With Stable Coronary Heart Disease: A CLARICOR (Effect of Clarithromycin on Mortality and Morbidity in Patients With Ischemic Heart Disease) Trial Substudy

BACKGROUND

We aimed to assess the associations and predictive powers between the soluble receptors for tumor necrosis factor (TNF)-α (TNFR1 and TNFR2) and cardiovascular outcomes in patients with stable coronary heart disease.

METHODS AND RESULTS

CLARICOR (Effect of Clarithromycin on Mortality and Morbidity in Patients With Ischemic Heart Disease) is a randomized clinical trial comparing clarithromycin with placebo in patients with stable coronary heart disease. The primary outcome was a composite of nonfatal acute myocardial infarction, unstable angina pectoris, cerebrovascular disease, and all-cause mortality. Patients were followed up for 10 years; discovery sample, those assigned placebo (1204 events in n=1998); and replication sample, those assigned clarithromycin (1220 events in n=1979). We used Cox regression adjusted for C-reactive protein level, established cardiovascular risk factors, kidney function, and cardiovascular drugs. After adjustments, higher serum levels of TNFR1 and TNFR2 were associated with the composite outcome in the discovery sample (hazard ratio per SD increase, 1.13; 95% confidence interval, 1.05-1.22; P=0.001 for TNFR1; hazard ratio, 1.16; 95% confidence interval, 1.08-1.24; P<0.001 for TNFR2). The associations were similar in the replication sample. The associations with the composite outcome were mainly driven by acute myocardial infarction, cardiovascular mortality, and noncardiovascular mortality. The addition of TNFR1 and TNFR2 to established cardiovascular risk factors improved prediction only modestly (<1%).

CONCLUSIONS

Increased concentrations of circulating TNFR1 and TNFR2 were associated with increased risks of cardiovascular events and mortality in patients with stable coronary heart disease. Yet, the utility of measuring TNFR1 and TNFR2 to improve risk prediction in these patients appears limited.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov. Unique identifier: NCT00121550.

Novel, Anti-hTNF-α Variable New Antigen Receptor Formats with Enhanced Neutralizing Potency and Multifunctionality, Generated for Therapeutic Development

The management of chronic inflammatory diseases, such as inflammatory bowel disease, psoriasis, and rheumatoid arthritis has significantly improved over the last decade with the clinical availability of anti-TNF-α biologics. Despite this undoubted treatment success, a combination of acquired resistance together with an increased risk of systemic complications, means that a significant number of patients either fail to find a suitable targeted therapy or frustratingly discover that an approach that did work is no longer efficacious. Here, we report the isolation and characterization of a new class of super-neutralizing anti-TNF-α biologics formats, the building blocks of which were originally derived as variable new antigen receptor (VNAR) domains from an immunized nurse shark. These parental small, stable VNAR monomers recognize and neutralize tumor necrosis factor (TNF)-α, in cell-based assays, at nanomolar concentrations. However, the simple, single-chain molecular architecture of VNARs allows for easy and multiple reformatting options. Through reformatting, we achieved a 50,000-fold enhancement in in vitro efficacy with super-neutralizing fusion proteins able to block TNF-α induced cytotoxicity in the 2–5 pM range while retaining other functionality through the addition of fusion proteins known to extend serum half-life in vivo. In an in vitro intestinal epithelial barrier dysfunction efficacy model, the lead VNAR domains, restored barrier function and prevented paracellular flux with comparable efficacy to adalimumab (Humira^®). In addition, all multivalent VNAR constructs restored trans-epithelial electrical resistance (TEER) to approximately 94% of the untreated control. Reformatted VNAR domains should be considered as a new class of biologic agents for the treatment of hTNF-α driven diseases; either used systemically with appropriate half-life extension or alternatively where site-specific delivery of small and stable neutralizers may provide improvements to current therapy options.

Risk of infection in patients with spondyloarthritis and ankylosing spondylitis receiving antitumor necrosis factor therapy: A meta-analysis of randomized controlled trials

Antitumor necrosis factor (TNF) agents have been widely used for the treatment of spondyloarthritis (SpA) and ankylosing spondylitis (AS). However, these agents may increase the risk of infection due to suppressing the immune response. The present meta-analysis was performed to systematically investigate the risk of overall infection, serious infection and tuberculosis in patients with SpA and AS treated with anti-TNF agents. Medline, Embase and the Cochrane library were searched for randomized controlled trials (RCTs) published between January 1998 and December 2015 about infection in patients with SpA receiving anti-TNF therapy. Data were pooled to obtain relative risks (RRs) along with their 95% confidence intervals (CIs). A total of 25 RCTs investigating SpA, including 12 investigating AS specifically, were eligible for the meta-analysis. Similar risks of overall infection were reported in patients with SpA (RR, 1.03; 95% CI, 0.92–1.15) and AS (RR, 1.06; 95% CI, 0.91–1.24) treated with anti-TNF agents. The RR of serious infection for patients with SpA or AS receiving anti-TNF therapy compared with a placebo was 1.27 (95% CI, 0.67–2.38) and 1.57 (95% CI, 0.63–3.91), respectively. In addition, 4 RCTs with outcomes of tuberculosis in patients with SpA receiving anti-TNF agents were identified, all in infliximab-treated patients (RR, 2.52; 95% CI, 0.53–12.09). However, due to the limited number of RCTs, this finding should be interpreted with caution. The present meta-analysis did not find any significantly increased risk of infection associated with anti-TNF therapy in patients with SpA or AS. However, due to short duration of follow-up in the RCTs and the rarity of serious infections and tuberculosis, patients treated with anti-TNF agents still should be closely monitored in clinical practice.

Rheumatoid arthritis: Recent advances on its etiology, role of cytokines and pharmacotherapy

An autoimmune disease is defined as a clinical syndrome resulted from an instigation of both T cell and B cell or individually, in the absence of any present infection or any sort of distinguishable cause. Clonal deletion of auto reactive cells remains the central canon of immunology for decades, keeping the role of T cell and B cell aside, which are actually the guards to recognize the entry of foreign body. According to NIH, 23.5 million Americans are all together affected by these diseases. They are rare, but with the exception of RA. Rheumatoid arthritis is chronic and systemic autoimmune response to the multiple joints with unknown ethology, progressive disability, systemic complications, early death and high socioeconomic costs. Its ancient disease with an old history found in North American tribes since 1500 BCE, but its etiology is yet to be explored. Current conventional and biological therapies used for RA are not fulfilling the need of the patients but give only partial responses. There is a lack of consistent and liable biomarkers of prognosis therapeutic response, and toxicity. Rheumatoid arthritis is characterized by hyperplasic synovium, production of cytokines, chemokines, autoantibodies like rheumatoid factor (RF) and anticitrullinated protein antibody (ACPA), osteoclastogensis, angiogenesis and systemic consequences like cardiovascular, pulmonary, psychological, and skeletal disorders. Cytokines, a diverse group of polypeptides, play critical role in the pathogenesis of RA. Their involvement in autoimmune diseases is a rapidly growing area of biological and clinical research. Among the proinflammatory cytokines, IL-1α/β and TNF-α trigger the intracellular molecular signalling pathway responsible for the pathogenesis of RA that leads to the activation of mesenchymal cell, recruitment of innate and adaptive immune system cells, activation of synoviocytes which in term activates various mediators including tumour necrosis factor-alpha (TNF-α), interleukin-1 (IL-1), interleukin-6 (IL-6) and interleukin-8 (IL-8), resulting in inflamed synovium, increase angiogenesis and decrease lymphangiogensis. Their current pharmacotherapy should focus on their three phases of progression i.e. prearthritis phase, transition phase and clinical phase. In this way we will be able to find a way to keep the balance between the pro and anti-inflammatory cytokines that is believe to be the dogma of pathogenesis of RA. For this we need to explore new agents, whether from synthetic or natural source to find the answers for unresolved etiology of autoimmune diseases and to provide a quality of life to the patients suffering from these diseases specifically RA.

The impact of immunogenicity of TNFα inhibitors in autoimmune inflammatory disease. A systematic review and meta-analysis

BACKGROUND

Monoclonal antibodies drugs directed against TNFα, TNFα inhibitors, are immunogenic, and consequent anti-drug antibodies (ADA) formation may decrease the functional drug concentration, resulting in a loss of response. We evaluated the impact of ADA on TNFα therapeutic response.

METHODS

We considered studies enrolling adult patients affected by autoimmune inflammatory disease in therapy with TNFα inhibitors. We collected data about study and population characteristics, treatment dosage, determination of ADA and adverse events (AE). We combined data in meta-analysis, calculating risk ratios (RR) for each study. p-Values<0.05 were considered as statistically significant. Methodological quality was evaluated. Analyses were performed with the STATA 11 and RevMan 5.3 softwares.

RESULTS

We included 34 studies enrolling 4273 patients. Of these, 794 (18.6%) developed ADA. Our analysis showed a significant reduction of response (RR 0.43, 95%CI 0.3-0.63) in patients with ADA respect to patients without, especially in patients treated with Infliximab (RR 0.37) or Adalimumab (RR 0.40). Furthermore, the administration of TNFα inhibitors produced a reaction at the infusion site in 17%, infection in 30% and serious AE in 5% of patients.

CONCLUSION

Detectable ADA significantly reduced TNFα inhibitors response. Drug administration can also cause injection site reaction and infections. Early detection of serum ADA levels may improve patients' management. Currently, there are many indications about the use of immunogenicity tests to guide the therapy, but information regarding how to implement it in clinical practice is needed.

CNS Demyelination with TNF-α Blockers

Tumor necrosis factor-α (TNF-α) blockers are a popular therapeutic choice in a number of inflammatory diseases. Thus far, five TNF- α blockers have been approved for clinical use (etanercept, infliximab, adalimumab, golimumab. and certolizumab). Despite being considered relatively safe, serious side effects associated with immune suppression have been reported, including central and peripheral nervous system (CNS) demyelinating disorders. It is still elusive whether these events are mere coincidence or a side effect of anti-TNF-α use. In this paper, we review the published case reports of CNS demyelination associated with anti-TNF-α therapy and present the follow-up of our 4 previously reported patients who developed neurologic symptoms suggestive of CNS demyelination after having received anti-TNF-α treatment. We also discuss the possible role of TNF-α blockers in demyelination.

Risk of infections using anti-TNF agents in rheumatoid arthritis, psoriatic arthritis, and ankylosing spondylitis: a systematic review and meta-analysis

INTRODUCTION

Five anti-tumor necrosis factor (anti-TNF) agents have received regulatory approval for use in rheumatology: adalimumab, golimumab, infliximab, certolizumab, and etanercept. Apart from their well-documented therapeutic value, it is still uncertain to what extent they are associated with an increased risk of infectious adverse events. Areas covered: We conducted a systematic review and meta-analysis of published randomized studies to determine the effect of anti-TNF drugs on the occurrence of infectious adverse events (serious infections; tuberculosis; opportunistic infections; any infection). We searched Medline, Embase, and the Cochrane Library up to May 2014 to identify eligible studies in adult patients with rheumatoid arthritis, psoriatic arthritis, or ankylosing spondylitis that evaluated anti-TNF drugs compared with placebo or no treatment. Expert opinion: Our study encompassed data from 71 randomized controlled trials involving 22,760 participants (range of follow-up: 1-36 months) and seven open label extension studies with 2,236 participants (range of follow-up: 6-48 months). Quantitative synthesis of the available data found statistically significant increases in the occurrence of any infections (20%), serious infections (40%), and tuberculosis (250%) associated with anti-TNF drug use, while the data for opportunistic infections were scarce. The quality of synthesized evidence was judged as moderate. Further evidence from registries and long-term epidemiological studies are needed to better define the relationship between anti-TNF agents and infection complications.

A trimeric structural fusion of an antagonistic tumor necrosis factor-α mutant enhances molecular stability and enables facile modification

Tumor necrosis factor-α (TNF) exerts its biological effect through two types of receptors, p55 TNF receptor (TNFR1) and p75 TNF receptor (TNFR2). An inflammatory response is known to be induced mainly by TNFR1, whereas an anti-inflammatory reaction is thought to be mediated by TNFR2 in some autoimmune diseases. We have been investigating the use of an antagonistic TNF mutant (TNFR1-selective antagonistic TNF mutant (R1antTNF)) to reveal the pharmacological effect of TNFR1-selective inhibition as a new therapeutic modality. Here, we aimed to further improve and optimize the activity and behavior of this mutant protein both in vitro and in vivo Specifically, we examined a trimeric structural fusion of R1antTNF, formed via the introduction of short peptide linkers, as a strategy to enhance bioactivity and molecular stability. By comparative analysis with R1antTNF, the trimeric fusion, referred to as single-chain R1antTNF (scR1antTNF), was found to retain in vitro molecular properties of receptor selectivity and antagonistic activity but displayed a marked increase in thermal stability. The residence time of scR1antTNF in vivo was also significantly prolonged. Furthermore, molecular modification using polyethylene glycol (PEG) was easily controlled by limiting the number of reactive sites. Taken together, our findings show that scR1antTNF displays enhanced molecular stability while maintaining biological activity compared with R1antTNF.

Cytokine-induced MMP13 Expression in Human Chondrocytes Is Dependent on Activating Transcription Factor 3 (ATF3) Regulation

Irreversible breakdown of cartilage extracellular matrix (ECM) by the collagenase matrix metalloproteinase 13 (MMP13) represents a key event in osteoarthritis (OA) progression. Although inflammation is most commonly associated with inflammatory joint diseases, it also occurs in OA and is thus relevant to the prevalent tissue destruction. Here, inflammation generates a cFOS AP-1 early response that indirectly affects MMP13 gene expression. To ascertain a more direct effect on prolonged MMP13 production we examined the potential molecular events occurring between the rapid, transient expression of cFOS and the subsequent MMP13 induction. Importantly, we show MMP13 mRNA expression is mirrored by nascent hnRNA transcription. Employing ChIP assays, cFOS recruitment to the MMP13 promoter occurs at an early stage prior to gene transcription and that recruitment of transcriptional initiation markers also correlated with MMP13 expression. Moreover, protein synthesis inhibition following early FOS expression resulted in a significant decrease in MMP13 expression thus indicating a role for different regulatory factors modulating expression of the gene. Subsequent mRNA transcriptome analyses highlighted several genes induced soon after FOS that could contribute to MMP13 expression. Specific small interfering RNA-mediated silencing highlighted that ATF3 was as highly selective for MMP13 as cFOS. Moreover, ATF3 expression was AP-1(cFOS/cJUN)-dependent and expression levels were maintained after the early transient cFOS response. Furthermore, ATF3 bound the proximal MMP13 AP-1 motif in stimulated chondrocytes at time points that no longer supported binding of FOS Consequently, these findings support roles for both cFOS (indirect) and ATF3 (direct) in effecting MMP13 transcription in human chondrocytes.

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.

Novel Human Three-Domain Antibody Fragments Against sTNFα as Well as tmTNFα with High Affinity Generated by the Combination of Ribosome Display and E. coli Expression System

Human tumour necrosis factor α (hTNFα) has been proved to be a validated therapeutic target in a number of immune-mediated inflammatory diseases (IMIDs). Fully human monoclonal antibodies (mAbs) that can neutralize soluble hTNFα (sTNFα) as well as transmembrane hTNFα (tmTNFα) are more desirable hTNFα antagonists. Here, we report that novel anti-hTNFα human low-molecular-weight MAbs have been selected and identified using both sTNFα and tmTNFα as target antigens by the combination of ribosome display and E. coli expression system for the first time. As a newly born engineering small molecular antibody, three-domain antibody fragment (VH /κ) provides an alternative promising molecular principle to generate biological agents for TNFα-dependent IMIDs. In this study, a panel of novel human VH /κs (F09, F21, F49 and F409) with high affinity (10(-10) -10(-9) mol/l) to neutralize sTNFα as well as tmTNFα was generated by the combination of ribosome display and E. coli expression system. Among the four clones, F21 and F409 could reduce cytotoxicity on L929 cells induced by sTNFα as well as tmTNFα effectively, and both of them had great potential to inhibit hTNFα-mediated NF-κB activation. Soluble F21 and F409 were also able to inhibit the binding of hTNFα to TNFR1 and TNFR2. The new human antibodies described here have desirable capability to neutralize sTNFα as well as tmTNFα effectively with high affinity and reasonable stability; this may provide an alternative approach for patients who are not responding adequately to currently available anti-TNFα agents.

Cis- and Trans-gnetin H from Paeonia suffruticosa suppress inhibitor kappa B kinase phosphorylation in LPS-stimulated human THP-1 cells

ETHNOPHARMACOLOGICAL RELEVANCE

The inflammatory response is an important mechanism in host defense; however, overstimulation and chronic inflammation are involved in many important human diseases. Currently, tumor necrosis factor-alpha blockers such as infliximab and adalimumab along with methotrexate are used in cases of severe and chronic disease. However, there are severe side effects and limitations associated with these treatments. Cis- and trans-gnetin H are compounds isolated from the seeds of Paeonia suffruticosa, a medicinal plant used in traditional Chinese medicine for the treatment of many conditions, including inflammatory diseases. In this study, we investigated possible anti-inflammatory mechanisms of cis- and trans-gnetin H against LPS-stimulated human THP-1 cells.

MATERIAL AND METHODS

PMA-differentiated THP-1 cells were pretreated with increasing concentrations of cis- and trans-gnetin H with or without LPS. Following treatment, cytotoxicity and the TNF-α, IL-1β, and IL-8 response were measured. We also characterized the nuclear translocation of NF-κB subunit p65 (RelA) by immunofluorescence and then investigated NF-κB activation by measuring the phosphorylation of NF-κB mediators, IKK-β, IκB α, and p65 by western blotting.

RESULTS

We found that cis- and trans-gnetin H significantly inhibited the cytokine response in a concentration-dependent manner without affecting cell viability. Cis- and trans-gnetin H effectively inhibited nuclear translocation of p65 and phosphorylation of IKK-β, IκB α, and p65. While both compounds showed promising anti-inflammatory effects, trans-gnetin H was determined to be more effective in suppressing cytokine responses.

CONCLUSION

We demonstrated that cis- and trans-gnetin H suppress cytokine response in LPS-stimulated THP-1 cells by preventing activation of key signaling molecules, IKK-β, IκB α, and p65, involved in the NF-κB pathway and suggest the use of cis- and trans-gnetin H in potential therapies for conditions and diseases associated with chronic inflammation.

Scintigraphic detection of TNF-driven inflammation by radiolabelled certolizumab pegol in patients with rheumatoid arthritis and spondyloarthritis

BACKGROUND

Biologicals are the cornerstone for many treatment algorithms in inflammatory arthritis. While tumour necrosis factor (TNF) inhibitors may achieve important responses in ∼50% of patients with rheumatoid arthritis (RA) and spondyloarthritis (SpA), a significant fraction of patients are partial or non-responders. We hypothesised that in vivo assessment of TNF by scintigraphy with 99mTc-radiolabelled certolizumab pegol (CZP) might lead to a more 'evidence-based biological therapy'.

OBJECTIVES

Our goal was to perform a proof-of-concept study of in vivo detection of TNF by immunoscintigraphy of a radiolabelled TNF inhibitor in RA and SpA, and correlate this with clinical, imaging findings and therapeutic outcome.

METHODS

CZP was conjugated with succinimidyl-6-hydrazino-nicotinamide and subsequently radiolabelled with Tc99m. Whole body and static images of hands, feet and sacroiliac joints of 20 patients (5 RA; 15 SpA) were acquired at 3 time points. Immunoscintigraphic findings were scored semiquantitatively. Subsequently, all patients were treated with CZP.

RESULTS

In peripheral joints, clinically affected joints or abnormal ultrasound findings were observed more frequently (p<0.001) in the scintigraphic-positive group. In patients with axial SpA, bone marrow edema on MRI was detected more frequently (p<0.001) in quadrants with tracer uptake. At the patient level, the odds of a joint remaining tender despite 24 weeks of CZP treatment was significantly smaller in joints with clear tracer uptake as compared with those with no uptake (OR=0.42, p=0.04).

CONCLUSIONS

Immunoscintigraphy with radiolabelled CZP demonstrated both axial and peripheral inflammation, and displayed good correlation with clinical features, conventional imaging and therapy response.

TRIAL REGISTRATION NUMBER

NCT01590966; Results.

Role of the protein annexin A1 on the efficacy of anti-TNF treatment in a murine model of acute colitis

TNF-α is involved in the mechanisms that initiate inflammatory bowel diseases (IBDs). Anti-TNF-α drugs, such as infliximab (IFX), cause non-responsiveness and side effects, indicating the need to investigate alternative therapies for these diseases. The anti-inflammatory protein, annexin A1 (AnxA1), has been associated with the protection of the gastrointestinal mucosa. To further address the role of endogenous AnxA1 on the TNF-α blockade efficacy in a murine model, we assessed colitis induced by Dextran Sulfate Sodium (DSS) in wild-type (WT) and AnxA1(-/-) Balb/c mice treated with IFX. We consistently observed endogenous AnxA1 prevented clinical and physiological manifestations of experimental colitis treated with IFX, additionally the manifestation of the disease was observed earlier in AnxA1(-)(/-) mice. Rectal bleeding, diarrhea, histological score, epithelial damages and collagen degradation caused by DSS were prevented following IFX treatment only in WT mice. IL-6 increased during colitis in WT and AnxA1(-)(/-) mice, decreasing under IFX treatment in WT. The influx of neutrophils and TNF-α secretion were largely elevated in AnxA1(-)(/-) mice when compared to WT mice. In the group WT/DSS+IFX, phagocytes were more susceptible to apoptosis following treatment with IFX. Endogenous expression of AnxA1 increased after DSS and decreased with IFX treatment, demonstrating an attenuated inflammatory response. The data indicate that AnxA1 contributes to the establishment of intestinal homeostasis after blocking of TNF-α was used as a treatment of IBD, constituting a key molecule in the mechanism of action and a potential biomarker of therapeutic efficacy.

Tumor necrosis factor antagonists in the treatment of multicentric reticulohistiocytosis: Current clinical evidence

Multicentric reticulohistiocytosis (MRH) is a rare and debilitating systemic disorder characterized by cutaneous nodules and destructive polyarthritis. Due to its unknown etiology, the treatment of MRH varies with different rates of success, which causes treatment options to be rather independent and empirical. In the present study, a case of a 48‑year‑old woman with a 12‑month history of polyarthralgia and skin nodules was reported. Biopsy samples, which were obtained from her skin eruption exhibited dermal infiltration with histiocytes and multinucleated giant cells. Immunohistochemical staining indicated positivity for CD68. The patient was diagnosed with MRH and treated with a combination therapy of infliximab, prednisolone and methotrexate. Her symptoms improved markedly within 2 weeks. Following the results of this case study, a systematic review of 17 cases of MRH treated with tumor necrosis factor (TNF) antagonists was performed, and the efficacy of anti‑TNF treatment in MRH was analyzed.

Investigating the potential side effects of anti-TNF therapy for rheumatoid arthritis: cause for concern?

There are now five anti-TNF drugs available for clinical use, and it will not be long before they are joined by biosimilar drugs. Some patients treated with selective TNF drugs may develop adverse events such as infections, malignancies, acute infusion and injection reactions, autoimmunity and cardiovascular effects. Registry data consistently show that, particularly during the first 6 months, anti-TNF drugs slightly increase the risk of serious infections of the skin, soft tissues and joints, but it does not seem to increase the risk of cancer other than nonmelanoma skin cancers. A number of studies have shown that the administration of biological agents can lead to the formation of neutralizing and nonneutralizing antibodies. Lipid levels increase, but the atherogenic index remains stable and qualitative changes to lipid particles may reduce the risk of cardiovascular diseases. Patients treated with anti-TNF drugs therefore need to be monitored regularly.

FcGR genetic polymorphisms and the response to adalimumab in patients with rheumatoid arthritis

AIM

The aim of our study was to explore the potential of FcGR genetic polymorphisms as a predictor of adalimumab efficacy in rheumatoid arthritis (RA) patients.

MATERIALS & METHODS

The study population was composed of 302 Dutch RA patients receiving adalimumab therapy. The FcGR2A (R131>H; rs1801274) and FcGR3A (F158>V; rs396991) genetic variants were genotyped using the TaqMan(®) allelic discrimination technology. Treatment outcome was evaluated with the use of the 28-joint disease activity score criteria (DAS28) and good response and remission were classified according to European League Against Rheumatism (EULAR) criteria.

RESULTS

Comparing allelic frequencies between responders and nonresponders, the presence of the FcGR2A*R allele was associated with EULAR good response at 14 weeks (p = 0.017, odds ratio: 1.53, 95% CI: 1.08-2.17). No significant association was found for FcGR3A, with good response or remission. The combined effect of both FcGR2A and FcGR3A SNPs showed a trend for association with EULAR good response (p-value = 0.041, odds ratio: 1.38, 95% CI: 1.01-1.89).

CONCLUSION

Our results indicate that FcGR polymorphisms could be a determinant of adalimumab efficacy in RA patients. Original submitted 28 July 2014; Revision submitted 19 December 2014.

Acquired immunodeficiencies and tuberculosis: focus on HIV/AIDS and diabetes mellitus

The spread of human immunodeficiency virus (HIV) infection within Africa led to marked increases in numbers of cases of tuberculosis (TB), and although the epidemic peaked in 2006, there were still 1.8 million new cases in 2013, with 29.2 million prevalent cases. Half of all TB cases in Africa are in those with HIV co-infection. A brief review of the well-documented main immunological mechanisms of HIV-associated increased susceptibility to TB is presented. However, a new threat is facing TB control, which presents itself in the form of a rapid increase in the number of people living with type II diabetes mellitus (T2DM), particularly in areas that are already hardest hit by the TB epidemic. T2DM increases susceptibility to TB threefold, and the TB burden attributable to T2DM is 15%. This review addresses the much smaller body of research information available on T2DM-TB, compared to HIV-TB comorbidity. We discuss the altered clinical presentation of TB in the context of T2DM comorbidity, changes in innate and adaptive immune responses, including lymphocyte subsets and T-cell phenotypes, the effect of treatment of the different comorbidities, changes in biomarker expression and genetic predisposition to the respective morbidities, and other factors affecting the comorbidity. Although significant gains have been made in improving our understanding of the underlying mechanisms of T2DM-associated increased susceptibility, knowledge gaps still exist that require urgent attention.

Tumor necrosis factor inhibitor therapy in ankylosing spondylitis: differential effects on pain and fatigue and brain correlates

Ankylosing spondylitis is associated with back pain and fatigue and impacts mobility but can be treated with tumor necrosis factor inhibitors (TNFi). The differential effects of TNFi treatment on multiple symptoms and the brain is not well delineated. Thus, we conducted a 2-part study. In study 1, we conducted a retrospective chart review in 129 ankylosing spondylitis patients to assess TNFi effects on pain, fatigue, motor function, mobility, and quality of life (QoL). After at least 10 weeks of TNFi treatment, patients had clinically significant improvements (>30%) in pain (including neuropathic pain), most disease and QoL factors, and normalized sensory detection thresholds. However, residual fatigue (mean = 5.3) was prominent. Although 60% of patients had significant relief of pain, only 22% of patients had significant relief of both pain and fatigue. Therefore, the preferential TNFi treatment effect on pain compared with fatigue could contribute to suboptimal effects on QoL. Part 2 was a prospective study in 14 patients to identify TNFi treatment effects on pain, fatigue, sensory and psychological factors, and brain cortical thickness based on 3T magnetic resonance imaging. Centrally, TNFi was associated with statistically significant cortical thinning of motor, premotor, and posterior parietal regions. Pain intensity reduction was associated with cortical thinning of the secondary somatosensory cortex, and pain unpleasantness reduction was associated with the cortical thinning of motor areas. In contrast, fatigue reduction correlated with cortical thinning of the insula, primary sensory cortex/inferior parietal sulcus, and superior temporal polysensory areas. This indicates that TNFi treatment produces changes in brain areas implicated in sensory, motor, affective, and cognitive functions.

Tumour necrosis factor-α inhibition can stabilize disease in progressive vitiligo

Tumour necrosis factor (TNF)-α, a proinflammatory cytokine central to many autoimmune diseases, has been implicated in the depigmentation process in vitiligo. We review its role in vitiligo by exploring its pro- and anti-inflammatory properties and examine the effects of blocking its actions with TNF-α antagonist therapeutics in reports available in the literature. We found that TNF-α inhibition halts disease progression in patients with progressive vitiligo but that, paradoxically, treatment can be associated with de novo vitiligo development in some patients when used for other autoimmune conditions, particularly when using adalimumab and infliximab. These studies reinforce the importance of stating appropriate outcomes measures, as most pilot trials propose to measure repigmentation, whereas halting depigmentation is commonly overlooked as a measure of success. We conclude that TNF-α inhibition has proven useful for patients with progressive vitiligo, where TNF-α inhibition is able to quash cytotoxic T-cell-mediated melanocyte destruction. However, a lingering concern for initiating de novo disease will likely prevent more widespread application of TNF inhibitors to treat vitiligo.

Recombinant H22(scFv) blocks CD64 and prevents the capture of anti-TNF monoclonal antibody. A potential strategy to enhance anti-TNF therapy

Tumor necrosis factor (TNF) is a pro-inflammatory cytokine that plays a critical role in many inflammatory diseases. Soluble TNF can be neutralized by monoclonal antibodies (mAbs), and this is a widely-used therapeutic approach. However, some patients do not respond to anti-TNF therapy due to the increased expression of CD64 on monocytes and macrophages. A recent study has shown that CD64 captures anti-TNF mAbs via their Fcγ domain, which induces the transcription of pro-inflammatory genes. Specific blocking of CD64 could therefore be a promising strategy to improve the response to anti-TNF therapy. We used the CD64-specific antibody fragment H22(scFv) and tested its activity against the human CD64(+) cell line HL-60. When stimulated with interferon gamma (IFN-γ), these cells represent a pro-inflammatory phenotype of the monocyte/macrophage lineage. We found that H22(scFv) binds selectively to and blocks CD64, preventing the capture of anti-TNF mAb. Importantly, H22(scFv) itself does not induce CD64 activation. We also found that transmembrane TNF on HL-60 cells stimulated with IFN-γ also contributes to the capture of anti-TNF mAb, although via their Fab domain. In conclusion, the specific blocking of CD64 by H22(scFv) could be used a possible anti-inflammatory mechanism for potentiating the effect of anti-TNF antibodies.

Regulation of tumour necrosis factor signalling: live or let die

Tumour necrosis factor (TNF) is a pro-inflammatory cytokine that has important roles in mammalian immunity and cellular homeostasis. Deregulation of TNF receptor (TNFR) signalling is associated with many inflammatory disorders, including various types of arthritis and inflammatory bowel disease, and targeting TNF has been an effective therapeutic strategy in these diseases. This Review focuses on the recent advances that have been made in understanding TNFR signalling and the consequences of its deregulation for cellular survival, apoptosis and regulated necrosis. We discuss how TNF-induced survival signals are distinguished from those that lead to cell death. Finally, we provide a brief overview of the role of TNF in inflammatory and autoimmune diseases, and we discuss up-to-date and future treatment strategies for these disorders.

A novel anti-TNF scFv constructed with human antibody frameworks and antagonistic peptides

The introduction of TNF inhibitors has revolutionized the treatment of some chronic inflammatory diseases, e.g., rheumatoid arthritis and Crohn's disease. However, immunogenicity is one of the important mechanisms behind treatment failure, and generally, switching to another TNF inhibitor will be the first choice for patients and doctors, which results in unmet need for novel anti-TNF agents. Small antibody molecules with less number of epitope may be valuable in less immunogenicity. In this study, with the help of computer-guided molecular design, single-chain variable fragment (scFv) TSA2 was designed using consensus frameworks of human antibody variable region as scaffold to display anti-TNF antagonistic peptides. TSA2 showed evidently improved bioactivity over TSA1 (anti-TNF scFv explored before) and almost similar activity as S-Remicade (the scFv form of Remicade, anti-TNF antibody approved by FDA), especially in inhibiting TNF-induced cytotoxicity and NF-κB activation. Human antibody consensus frameworks with less immunogenicity have been used in the designing of VH domain antibody, scFv TSA1 and TSA2. A serial of TNF-related works convinced us that the novel design strategy was feasible and could be used to design inhibitors targeting more other molecules than TNF-α. More importantly, these designed inhibitors derived from computer modeling may form a virtual antibody library whose size depends on the number of candidate antagonistic peptides. It will be molecular-targeted virtual antibody library because of the specific antagonistic peptides and the potential antibodies could be determined by virtual screening and then confirmed by biologic experiments.

Alarmin' Immunologists: IL-33 as a Putative Target for Modulating T Cell-Dependent Responses

IL-33 is a known member of the IL-1 cytokine superfamily classically named “atypical” due to its diverse functions. The receptor for this cytokine is the ST2 chain (or IL-1RL1), part of the IL-1R family, and the accessory chain IL-1R. ST2 can be found as both soluble and membrane-bound forms, property that explains, at least in part, its wide range of functions. IL-33 has increasingly gained our attention as a potential target to modulate immune responses. At the beginning, it was known as one of the participants during the development of allergic states and other Th2-mediated responses and it is now accepted that IL-33 contributes to Th1-driven pathologies as demonstrated in animal models of experimental autoimmune encephalomyelitis (EAE), collagen-induced arthritis, and trinitrobenzene sulfonic acid-induced experimental colitis, among others. Interestingly, current data are placing IL-33 as a novel regulator of immune tolerance by affecting regulatory T cells (Tregs); although the mechanism is not fully understood, it seems that dendritic cells and myeloid suppressor-derived cells may be cooperating in the generation and/or establishment of IL-33-mediated tolerance. Here, we review the most updated literature on IL-33, its role on T cell biology, and its impact in immune tolerance.

Mechanisms of human autoimmunity

Autoimmune reactions reflect an imbalance between effector and regulatory immune responses, typically develop through stages of initiation and propagation, and often show phases of resolution (indicated by clinical remissions) and exacerbations (indicated by symptomatic flares). The fundamental underlying mechanism of autoimmunity is defective elimination and/or control of self-reactive lymphocytes. Studies in humans and experimental animal models are revealing the genetic and environmental factors that contribute to autoimmunity. A major goal of research in this area is to exploit this knowledge to better understand the pathogenesis of autoimmune diseases and to develop strategies for reestablishing the normal balance between effector and regulatory immune responses.

Risk of hepatitis B virus reactivation in rheumatoid arthritis patients undergoing biologic treatment: Extending perspective from old to newer drugs

Hepatitis B virus (HBV) reactivation in rheumatoid arthritis (RA) patients undergoing biological therapy is not infrequent. This condition can occur in patients with chronic hepatitis B as well as in patients with resolved HBV infection. Current recommendations are mainly focused on prevention and management strategies of viral reactivation under tumor necrosis factor-α inhibitors or chimeric monoclonal antibody rituximab. In recent years, growing data concerning HBV reactivation in RA patients treated with newer biological drugs like tocilizumab and abatacept have cumulated. In this review, epidemiology, pathogenesis and natural history of HBV infection have been revised first, mainly focusing on the role that specific therapeutic targets of current biotechnological drugs play in HBV pathobiology; finally we have summarized current evidences from scientific literature, including either observational studies and case reports as well, concerning HBV reactivation under different classes of biological drugs in RA patients. Taking all these evidences into account, some practical guidelines for screening, vaccination, prophylaxis and treatment of HBV reactivation have been proposed.