Monoclonal antibody treatments for rheumatoid arthritis

Delanzomib, a Novel Proteasome Inhibitor, Combined With Adalimumab Drastically Ameliorates Collagen-Induced Arthritis in Rats by Improving and Prolonging the Anti-TNF-α Effect of Adalimumab

Delanzomib is a novel proteasome inhibitor initially developed for treating multiple myeloma. It was found to inhibit the expression of tumor necrosis factor alpha (TNF-α). This study aimed to investigate the ameliorating effect of delanzomib on collagen-induced arthritis (CIA) and to explore the pharmacodynamics and pharmacokinetics (PK) interactions between delanzomib and adalimumab. Rats with CIA were randomly assigned to receive the treatment with delanzomib, adalimumab, delanzomib combined with adalimumab, or placebo. Visual inspection and biochemical examinations including TNF-α, interleukin 6, and C-reactive protein were performed to assess arthritis severity during the treatment. The adalimumab concentration in rats was determined to evaluate the PK interaction between delanzomib and adalimumab. Also, the levels of neonatal Fc receptor (FcRn) and FcRn mRNA were measured to explore the role of FcRn in the PK interaction between delanzomib and adalimumab. As a result, delanzomib combined with adalimumab exhibited stronger anti-arthritis activity than a single drug because both drugs synergistically reduced TNF-α level in vivo. Delanzomib also decreased adalimumab elimination in rats by increasing the level of FcRn. The slower elimination of adalimumab in rats further prolonged the anti-TNF-α effect of adalimumab. Moreover, FcRn level was increased by delanzomib via suppressing FcRn degradation rather than promoting FcRn production. In conclusion, delanzomib combined with adalimumab may be a potential therapeutic approach for treating rheumatoid arthritis. The initial finding that the PK interaction occurred between delanzomib and adalimumab may have clinical relevance for patients who simultaneously take proteasome inhibitors and anti-TNF-α therapeutic proteins.

A novel dendritic mesoporous silica based sustained hydrogen sulfide donor for the alleviation of adjuvant-induced inflammation in rats

Purpose

S-propargyl-cysteine (SPRC), an excellent endogenous hydrogen sulfide (H₂S) donor, could elevate H₂S levels via the cystathionine γ-lyase (CSE)/H₂S pathway both in vitro and in vivo. However, the immediate release of H₂S in vivo and daily administration of SPRC potentially limited its clinical use.

Methods

To solve the fore-mentioned problem, in this study, the dendritic mesoporous silica nanoparticles (DMSN) was firstly prepared, and a sustained H₂S delivery system consisted of SPRC and DMSN (SPRC@DMSN) was then constructed. Their release profiles, both in vitro and in vivo, were investigated, and their therapeutical effect toward adjuvant-induced arthritis (AIA) rats was also studied.

Results

The spherical morphology of DMSN could be observed under scanning Electron Microscope (SEM), and the transmission electron microscope (TEM) images showed a central-radiational pore channel structure of DMSN. DMSN showed excellent SPRC loading capacity and attaining a sustained releasing ability than SPRC both in vitro and in vivo, and the prolonged SPRC releasing could further promote the release of H₂S in a sustained manner through CSE/H₂S pathway both in vitro and in vivo. Importantly, the SPRC@DMSN showed promising anti-inflammation effect against AIA in rats was also observed.

Conclusions

A sustained H₂S releasing donor consisting of SPRC and DMSN was constructed in this study, and this sustained H₂S releasing donor might be of good use for the treatment of AIA.

A novel monoclonal antibody cross-reactive with both human and mouse α9 integrin useful for therapy against rheumatoid arthritis

This study introduces a novel monoclonal anti-α9 integrin antibody (MA9-413) with human variable regions, isolated by phage display technology. MA9-413 specifically binds to both human and mouse α9 integrin by recognizing a conserved loop region designated as L1 (amino acids 104-122 of human α9 integrin). MA9-413 inhibits human and mouse α9 integrin-dependent cell adhesion to ligands and suppresses synovial inflammation and osteoclast activation in a mouse model of arthritis. This is the first monoclonal anti-α9 integrin antibody that can react with and functionally inhibit both human and mouse α9 integrin. MA9-413 allows data acquisition both in animal and human pharmacological studies without resorting to surrogate antibodies. Since MA9-413 showed certain therapeutic effects in the mouse arthritis model, it can be considered as a useful therapy against rheumatoid arthritis and other α9 integrin-associated diseases.

PSTPIP2 attenuates joint damage and suppresses inflammation in adjuvant-induced arthritis

Proline-serine-threonine-phosphatase-interacting protein 2 (PSTPIP2) is related to inflammation. In this study, we investigated the function of PSTPIP2 in adjuvant-induced arthritis (AIA) by using adeno-associated virus (AAV) to overexpress PSTPIP2 in rat. AIA rats were developed by injecting Lewis rats with complete Freund's adjuvant (CFA) on day 0. AAV-empty or AAV-PSTPIP2, or PBS was administered intraarticularly into each knee joint on day 8 postinduction. All animals were killed at day 18 after adjuvant injection. WB was used to detect the expression of PSTPIP2 in rat synovial tissues. Fluorescence microscopy showed the transduction efficiency in synovial tissue. The morphology of arthritic joints was examined by HE, safranin O/fast green, or Toluidine blue staining. The bone destruction was examined via X-ray and micro-CT analysis. Immunohistochemical analysis or TRAP staining were used to investigate the role of PSTPIP2 in osteoclasts and the expression of PSTPIP2 in synovial tissue. RT-qPCR and ELISA were used to examine the expression of pro-inflammatory cytokines in synovial tissue or serum. AIA rats were found to have decreased PSTPIP2 expression and AIA-associated bone loss and inflammatory infiltration. We showed that administration of AAV-PSTPIP2 before arthritis onset significantly reduces the severity of AIA. PSTPIP2 was highly expressed in synovial cells. In addition, inflammatory responses and the number of osteoclasts were reduced with AAV-PSTPIP2 treatment. These findings demonstrate that PSTPIP2 may improve the severity of AIA by inhibiting the function of fibroblast-like synoviocytes, suppressing inflammation and reducing the number of osteoclasts.

miR-449a inhibits cell proliferation, migration, and inflammation by regulating high-mobility group box protein 1 and forms a mutual inhibition loop with Yin Yang 1 in rheumatoid arthritis fibroblast-like synoviocytes

Background

We previously found that high-mobility group box protein 1 (HMGB1) promoted cell proliferation, migration, invasion, and autophagy in rheumatoid arthritis fibroblast-like synoviocytes (RA-FLS), but little is known about its regulatory mechanism. The aim of this study was to investigate the regulatory mechanism of HMGB1 at the posttranscription level.

Methods

Real-time qPCR, CCK-8 cell proliferation assay, transwell cell migration assay, enzyme-linked immunosorbent assay (ELISA), and western blotting were used in this study. The targeting relationship between miRNA and mRNA was presented by the luciferase reporter assay.

Results

MiR-449a was downregulated in RA synovial tissue and inhibited RA-FLS proliferation, migration, and IL-6 production. MiR-449a directly targeted HMGB1 and inhibited its expression. Yin Yang 1(YY1) negatively regulated miR-449a expression and formed a mutual inhibition loop in RA-FLS. MiR-449a inhibited TNFα-mediated HMGB1 and YY1 overexpression and IL-6 production.

Conclusions

Our results reveal the regulatory mechanism of HMGB1 in RA and demonstrate that miR-449a is a crucial molecule in RA pathogenesis and a suitable candidate for miRNA replacement therapies in RA.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1920-0) contains supplementary material, which is available to authorized users.

Comparative Studies of Different Extracts from Eucommia ulmoides Oliv. against Rheumatoid Arthritis in CIA Rats

To compare efficacy of different extracts from Eucommia ulmoides Oliv. with both immune inflammation and joint destruction in collagen induced arthritis (CIA) rat model. Rats were divided into normal group (Nor), control group (CIA), TG group (treated with tripterygium glycoside), E70 group (treated with 70% ethanol extract from Eucommia ulmoides Oliv.), EA group (treated with ethyl acetate fraction from E70), and EN group (treated with n-butyl alcohol fraction from E70). All extracts from Eucommia ulmoides Oliv. could significantly inhibit ankle swelling, pathological manifestations, and cytokine levels in serum and spleen, by using foot volume measurement, H&E staining, ELISA, and RT-QPCR methods, respectively. All extracts could significantly inhibit rough joint surface and marginal osteophytes, improve RANKL/OPG ratio, and decrease MMP-9 expression, by using micro-CT and immunohistochemical staining. The activation of IKK/NF-κB signaling pathway was also inhibited by all extracts. In addition, ethyl acetate fraction from E70 presented better effect on RANKL/OPG system. This study identified effective extracts from Eucommia ulmoides Oliv. relieving immune inflammation and maintaining structural integrity of joints in CIA rats.

Molecular property diagnostic suite (MPDS): Development of disease-specific open source web portals for drug discovery

Molecular property diagnostic suite (MPDS) is a Galaxy-based open source drug discovery and development platform. MPDS web portals are designed for several diseases, such as tuberculosis, diabetes mellitus, and other metabolic disorders, specifically aimed to evaluate and estimate the drug-likeness of a given molecule. MPDS consists of three modules, namely data libraries, data processing, and data analysis tools which are configured and interconnected to assist drug discovery for specific diseases. The data library module encompasses vast information on chemical space, wherein the MPDS compound library comprises 110.31 million unique molecules generated from public domain databases. Every molecule is assigned with a unique ID and card, which provides complete information for the molecule. Some of the modules in the MPDS are specific to the diseases, while others are non-specific. Importantly, a suitably altered protocol can be effectively generated for another disease-specific MPDS web portal by modifying some of the modules. Thus, the MPDS suite of web portals shows great promise to emerge as disease-specific portals of great value, integrating chemoinformatics, bioinformatics, molecular modelling, and structure- and analogue-based drug discovery approaches.

The Role of High-Mobility Group Box-1 and Its Crosstalk with Microbiome in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, definitely disabling, and potentially severe autoimmune disease. Although an increasing number of patients are affected, a key treatment for all patients has not been discovered. High-mobility group box-1 (HMGB1) is a nuclear protein passively and actively released by almost all cell types after several stimuli. HMGB1 is involved in RA pathogenesis, but a convincing explanation about its role and possible modulation in RA is still lacking. Microbiome and its homeostasis are altered in patients with RA, and the microbiota restoration has been proposed to patients with RA. The purpose of the present review is to analyze the available evidences regarding HMGB1 and microbiome roles in RA and the possible implications of the crosstalk between the nuclear protein and microbiome in understanding and possibly treating patients affected by this harmful condition.

Salicylate-based phytopharmaceuticals induce adaptive cytokine and chemokine network responses in human fibroblast cultures

BACKGROUND

Cytokines and chemokines (CC) play a central role in immunoregulatory and inflammatory processes. Neutralising antibodies for single proinflammatory cytokines have developed into a powerful, though expensive and not always curative therapeutic strategy for severe diseases. Considering the redundancy of CC functions, network (N) rather than single target approaches are essential. Phytopharmaceuticals, common adjuvant therapies, are known modulators of a broad spectrum of CCs, but as complex mixtures with multiple targets they have not been systematically investigated. We investigated the effect of clinically established salicylate-based phytopharmaceuticals alone or in combination on CCNs under non-inflammatory and inflammatory conditions, using fibroblasts being a major source of cytokines in connective tissue diseases.

METHODS

Synchronised human skin fibroblasts (HSKF) were treated for 6 h with standardised fluid plant extracts (E) of Populus tremula L. [end concentration: 0.06%, 0.1%], Solidago virgaurea L. [0.02%, 0.1%], Fraxinus excelsior L. [0.02%, 0.1%], an established combination of the three extracts-STW1 [0.05, 0.1%] and acetyl salicylic acid (ASA) [30 µg/ml], individually or in the presence of lipopolysaccharides (LPS) [10 µg/ml]. Cell lysates were profiled for 23 cytokines. Supernatants were investigated for IL-6 and IL-8 release (ELISA). Total RNA was isolated for gene-expression profiling.

RESULTS

Under non-inflammatory conditions P. tremula E and ASA increased cellular proteins (P) IL-8 and IL-10; S. virgaurea E modulated IL-1α, IL-10, IL-15 and Groα (P). F. excelsior decreased IL-1α and IL-15 (P). The combination of the three extracts (STW1) modulated IL-1α, IL-3 and TNF-ß (P). LPS stimulation increased cellular IL-8, Groα, MCP-1 and RANTES (P) and increased the secretion of IL-6 and IL-8 into the medium. Under these inflammatory conditions F. excelsior reduced GMCSF, GCSF and RANTES. STW1 reduced IL-1α, IL-8, Groα, and MCP-1(P). Secretion of IL-8 and IL-6 was reduced by STW1 and ASA. Gene expression profiles supported non-additive CCN profiles.

CONCLUSION

Salicylate based phytopharmaceuticals provoke cellular pro-and anti-inflammatory CCN responses under non-stress conditions, which adapt to anti-inflammatory responses after LPS-stimulation. CCN-profiles of the single extracts are not additives in combination. A simultaneous activation of cellular pro- and anti-inflammatory cytokines might heighten the immunological reactivity status of a cell.

Downregulation of miR-106b attenuates inflammatory responses and joint damage in collagen-induced arthritis

Objective

miRNAs are small, signal-strand, non-coding RNAs that function in post-transcriptional regulation. We analysed the in vivo effect of miR-106b (miR-106b-5p) on inflammatory bone loss in CIA mice.

Methods

CIA mice are developed by injecting DAB/1 mice with bovine type II collagen containing Freund's adjuvant and then the in vivo effect of miR-106b is examined. On day 22, mice were given lentiviral negative control, lentiviral-mediated miR-106b mimics or lentiviral-mediated miR-106b inhibitor via orbital injection on a weekly basis. Morphological changes in the ankle joints were assessed via micro-CT and histopathology and cytokine expression levels were examined via immunohistochemical staining, ELISA or flow cytometric analysis. miR-106b and osteoclastic-related gene expression was evaluated via quantitative real-time PCR.

Results

CIA mice were found to have increased miR-106b expression and CIA-associated bone loss and inflammatory infiltration. miR-106b inhibitor treatment markedly decreased arthritis incidence and attenuated bone destruction and histological severity compared with the control group. Moreover, miR-106b inhibitor treatment suppressed RANK ligand (RANKL) expression, increased osteoprotegerin (OPG) expression and reduced the RANKL:OPG ratio in CIA mice. miR-106b inhibition also significantly decreased inflammatory mediator production in joint sections and reduced serum pro-inflammatory cytokine levels when compared with the control group. Additionally, miR-106b inhibition decreased tartrate-resistant acid phosphatase-positive cell numbers and suppressed murine bone marrow macrophage differentiation.

Conclusion

These findings indicate that miR-106b inhibition can ameliorate CIA-associated inflammation and bone destruction and thus may serve as a potential therapeutic for human RA treatment.

Modeled Health Economic Impact of a Hypothetical Certolizumab Pegol Risk-Sharing Scheme for Patients with Moderate-to-Severe Rheumatoid Arthritis in Finland

PURPOSE

To model the American College of Rheumatology (ACR) outcomes, cost-effectiveness, and budget impact of certolizumab pegol (CZP) (with and without a hypothetical risk-sharing scheme at treatment initiation for biologic-naïve patients) versus the current mix of reimbursed biologics for treatment of moderate-to-severe rheumatoid arthritis (RA) in Finland.

METHODS

A probabilistic model with 12-week cycles and a societal approach was developed for the years 2015-2019, accounting for differences in ACR responses (meta-analysis), mortality, and persistence. The risk-sharing scheme included a treatment switch and refund of the costs associated with CZP acquisition if patients failed to achieve ACR20 response at week 12. For the current treatment mix, ACR20 at week 24 determined treatment continuation. Quality-adjusted life years were derived on the basis of the Health Utilities Index.

RESULTS

In the Finnish target population, CZP treatment with a risk-sharing scheme led to a estimated annual net expenditure decrease ranging from 1.7% in 2015 to 5.6% in 2019 compared with the current treatment mix. Per patient over the 5 years, CZP risk sharing was estimated to decrease the time without ACR response by 5%-units, decrease work absenteeism by 24 days, and increase the time with ACR20, ACR50, and ACR70 responses by 5%-, 6%-, and 1%-units, respectively, with a gain of 0.03 quality-adjusted life years. The modeled risk-sharing scheme showed reduced costs of €7866 per patient, with a more than 95% probability of cost-effectiveness when compared with the current treatment mix.

CONCLUSION

The present analysis estimated that CZP, with or without the risk-sharing scheme, is a cost-effective alternative treatment for RA patients in Finland. The surplus provided by the CZP risk-sharing scheme could fund treatment for 6% more Finnish RA patients.

FUNDING

UCB Pharma.

Safety and efficacy of ocrelizumab in rheumatoid arthritis patients with an inadequate response to methotrexate or tumor necrosis factor inhibitors: a systematic review and meta-analysis

We conducted this systematic reviews and meta-analysis to investigate the safety and efficacy of ocrelizumab in patients with active rheumatoid arthritis (RA) who exhibited resistance or intolerance to methotrexate or biological therapy. We performed a web-based literature search of PubMed, Google Scholar, EBSCO, Scopus, Embase, and Web of science for studies that compared ocrelizumab plus methotrexate versus methotrexate plus placebo in RA patients. Data were extracted from eligible studies and pooled as risk ratios (RR), using RevMan software. Pooling data from four RCTs (2230 patients) showed that ocrelizumab plus methotrexate were superior to methotrexate plus placebo at 24 weeks in terms of improvement on the American college of rheumatology (ACR20, ACR50, and ACR70) criteria (p < 0.00001), disease activity score 28-ESR (RR = 3.77, 95% CI [2.47, 5.74], p < 0.00001), and Sharp/van der Heijde radiological score (RR = 1.63, 95% CI [1.43, 1.85], p < 0.00001). These effects were consistent among all ocrelizumab doses. The rates of serious adverse events were comparable between the ocrelizumab and placebo containing groups (RR = 1, 95% CI [0.78, 1.28], p = 0.98). However, infusion related reactions were significantly higher in ocrelizumab group (RR = 2.13, 95% CI [1.69, 2.68], p < 0.00001), compared to placebo group. The combination of ocrelizumab plus methotrexate was superior to methotrexate plus placebo on all clinical and radiographic improvement scales. The incidence of adverse events, including serious adverse events, was comparable between both groups. Future trials should investigate the efficacy of ocrelizumab alone and develop strategies to alleviate its related infusion reactions.

Fibroblast-like synoviocytes-dependent effector molecules as a critical mediator for rheumatoid arthritis: Current status and future directions

Rheumatoid arthritis (RA) is a systemic-autoimmune-mediated disease characterized by synovial hyperplasia and progressive destruction of joint. Currently available biological agents and inhibitor therapy that specifically target tumor necrosis factor-α, interleukin 1β (IL-1β), IL-6, T cells, B cells, and subcellular molecules (p38 mitogen-activated protein kinase and janus kinase) cannot facilitate complete remission in all patients and are unable to cure the disease. Therefore, further potent therapeutic targets need to be identified for effective treatment and successful clinical outcomes in patients with RA. Scientific breakthroughs have brought new insights regarding fibroblast-like synoviocytes (FLS), a major constituent of the synovial hyperplasia. These play a pivotal role in RA invading cartilage and bone tissue. Currently there are no effective therapies available that specifically target these aggressive cells. Recent evidences indicate that FLS-dependent effector molecules (toll-like receptors, nodal effector molecules, hypoxia-inducible factor, and IL-17) have emerged as important mediators of RA. In this review, we discuss the pathological features and recent advances in understanding the role of FLS-dependent effector molecules in the disease onset of RA. Pharmacological inhibition of FLS-dependent effector molecules might be a promising option for FLS-targeted therapy in RA.

Methotrexate affects HMGB1 expression in rheumatoid arthritis, and the downregulation of HMGB1 prevents rheumatoid arthritis progression

High-mobility group box 1 (HMGB1) is associated with the development of rheumatoid arthritis (RA). Recent studies have shown that methotrexate (MTX) may inhibit the expression of HMGB1. This study examined whether HMGB1 might be involved in the treatment of RA using MTX. Synovial tissues were collected from RA patients who were treated with MTX for at least 6 months (RA-MTX group, 7 cases) and from those without MTX treatment (RA-noMTX group, 7 cases). Additionally, patients with osteoarthritis (OA group, 7 cases) were used as controls. The expression and locations of HMGB1 in the tissues were detected using real-time PCR, western blot, and immunohistochemistry. Additionally, OA-fibroblast-like synoviocytes (FLSs) and RA-FLSs were isolated and cultured, and the expression of HMGB1 was reduced in these cells by transfection with HMGB1 siRNA. Cell proliferation, migration, and invasion abilities were detected. Furthermore, the effects of HMGB1 on matrix metalloproteinase (MMP)-2 and MMP-13 were measured using western blot analysis. At the tissue level, HMGB1 expression in synovial membrane did not differ significantly between the OA and RA-MTX groups, but was significantly lower in these groups than in the RA-noMTX group. In cell experiments, the cell doubling time in the RA-FLS HMGB1 siRNA group was significantly extended compared with that in the RA-FLS negative control (NC)-siRNA group. The amount of cell migration and invasion in the RA-FLS HMGB1 siRNA group was significantly lower compared with that in the NC-siRNA group; the MMP-2 and MMP-13 expression levels were also lower. These results showed that MTX reduced HMGB1 expression in RA synovial tissues, and through the downregulation of HMGB1 expression in tissues, MTX may slow disease progression of RA.

Alleviation of collagen-induced arthritis by the benzoxathiole derivative BOT-4-one in mice: Implication of the Th1- and Th17-cell-mediated immune responses

Autoimmune rheumatoid arthritis is characterized by chronic inflammation and hyperplasia in the synovial joints. Although the cause of rheumatoid arthritis is largely unknown, substantial evidence has supported the importance of immune cells and inflammatory cytokines in the initiation and progression of this disease. Herein, we demonstrated that the benzoxathiole derivative 2-cyclohexylimino-6-methyl-6,7-dihydro-5H-benzo[1,3]oxathiol-4-one (BOT-4-one) alleviated type II collagen-induced arthritis in a mouse model. The levels of pro-inflammatory cytokines are elevated in both human patients with rheumatoid arthritis and mice with collagen-induced arthritis. BOT-4-one treatment reduced the levels of pro-inflammatory cytokines in mice and endotoxin-stimulated macrophages. BOT-4-one treatment suppressed the polarization of Th1- and Th17-cell subsets by inhibiting the expression and production of their lineage-specific master transcription factors and cytokines, as well as activation of signal transducer and activator of transcription proteins. In addition, BOT-4-one inhibited mitogen-activated protein kinase and NF-kappaB signaling as well as the transcriptional activities and DNA-binding of transcription factors, including activator protein-1, cAMP response element-binding protein and NF-kappaB. Our results suggest that BOT-4-one may have therapeutic potential for the treatment of chronic inflammation associated with autoimmune rheumatoid arthritis.

A novel NF-κB/YY1/microRNA-10a regulatory circuit in fibroblast-like synoviocytes regulates inflammation in rheumatoid arthritis

The main etiopathogenesis of rheumatoid arthritis (RA) is overexpressed inflammatory cytokines and tissue injury mediated by persistent NF-κB activation. MicroRNAs widely participate in the regulation of target gene expression and play important roles in various diseases. Here, we explored the mechanisms of microRNAs in RA. We found that microRNA (miR)-10a was downregulated in the fibroblast-like synoviocytes (FLSs) of RA patients compared with osteoarthritis (OA) controls, and this downregulation could be triggered by TNF-α and IL-1β in an NF-κB-dependent manner through promoting the expression of the YingYang 1 (YY1) transcription factor. Downregulated miR-10a could accelerate IκB degradation and NF-κB activation by targeting IRAK4, TAK1 and BTRC. This miR-10a-mediated NF-κB activation then significantly promoted the production of various inflammatory cytokines, including TNF-α, IL-1β, IL-6, IL-8, and MCP-1, and matrix metalloproteinase (MMP)-1 and MMP-13. In addition, transfection of a miR-10a inhibitor accelerated the proliferation and migration of FLSs. Collectively, our data demonstrates the existence of a novel NF-κB/YY1/miR-10a/NF-κB regulatory circuit that promotes the excessive secretion of NF-κB-mediated inflammatory cytokines and the proliferation and migration of RA FLSs. Thus, miR-10a acts as a switch to control this regulatory circuit and may serve as a diagnostic and therapeutic target for RA treatment.

Bispecific antibodies and their applications

Bispecific antibodies (BsAbs) recognize two different epitopes. This dual specificity opens up a wide range of applications, including redirecting T cells to tumor cells, blocking two different signaling pathways simultaneously, dual targeting of different disease mediators, and delivering payloads to targeted sites. The approval of catumaxomab (anti-EpCAM and anti-CD3) and blinatumomab (anti-CD19 and anti-CD3) has become a major milestone in the development of bsAbs. Currently, more than 60 different bsAb formats exist, some of them making their way into the clinical pipeline. This review summarizes diverse formats of bsAbs and their clinical applications and sheds light on strategies to optimize the design of bsAbs.

Peptides and peptidomimetics as immunomodulators

Peptides and peptidomimetics can function as immunomodulating agents by either blocking the immune response or stimulating the immune response to generate tolerance. Knowledge of B- or T-cell epitopes along with conformational constraints is important in the design of peptide-based immunomodulating agents. Work on the conformational aspects of peptides, synthesis and modified amino acid side chains have contributed to the development of a new generation of therapeutic agents for autoimmune diseases and cancer. The design of peptides/peptidomimetics for immunomodulation in autoimmune diseases such as multiple sclerosis, rheumatoid arthritis, systemic lupus and HIV infection is reviewed. In cancer therapy, peptide epitopes are used in such a way that the body is trained to recognize and fight the cancer cells locally as well as systemically.

HMGB1 in health and disease

Complex genetic and physiological variations as well as environmental factors that drive emergence of chromosomal instability, development of unscheduled cell death, skewed differentiation, and altered metabolism are central to the pathogenesis of human diseases and disorders. Understanding the molecular bases for these processes is important for the development of new diagnostic biomarkers, and for identifying new therapeutic targets. In 1973, a group of non-histone nuclear proteins with high electrophoretic mobility was discovered and termed high-mobility group (HMG) proteins. The HMG proteins include three superfamilies termed HMGB, HMGN, and HMGA. High-mobility group box 1 (HMGB1), the most abundant and well-studied HMG protein, senses and coordinates the cellular stress response and plays a critical role not only inside of the cell as a DNA chaperone, chromosome guardian, autophagy sustainer, and protector from apoptotic cell death, but also outside the cell as the prototypic damage associated molecular pattern molecule (DAMP). This DAMP, in conjunction with other factors, thus has cytokine, chemokine, and growth factor activity, orchestrating the inflammatory and immune response. All of these characteristics make HMGB1 a critical molecular target in multiple human diseases including infectious diseases, ischemia, immune disorders, neurodegenerative diseases, metabolic disorders, and cancer. Indeed, a number of emergent strategies have been used to inhibit HMGB1 expression, release, and activity in vitro and in vivo. These include antibodies, peptide inhibitors, RNAi, anti-coagulants, endogenous hormones, various chemical compounds, HMGB1-receptor and signaling pathway inhibition, artificial DNAs, physical strategies including vagus nerve stimulation and other surgical approaches. Future work further investigating the details of HMGB1 localization, structure, post-translational modification, and identification of additional partners will undoubtedly uncover additional secrets regarding HMGB1's multiple functions.

Rapid-onset clinical and mechanistic effects of anti-C5aR treatment in the mouse collagen-induced arthritis model

Preclinical evidence supports targeting the C5a receptor (C5aR) in rheumatoid arthritis (RA). To support ongoing clinical development of an anti-C5aR monoclonal antibody, we have investigated for the first time the mechanism of action and the pharmacodynamics of a blocking anti-murine C5aR (anti-mC5aR) surrogate antibody in mouse collagen-induced arthritis (CIA). First, efficacy was demonstrated in a multiple-dose treatment study. Almost complete inhibition of clinical disease progression was obtained, including reduced bone and cartilage destruction in anti-mC5aR-treated mice. Then, the mechanism of action was examined by looking for early effects of anti-mC5aR treatment in single-dose treatment studies. We found that 48 h after single-dose treatment with anti-mC5aR, the neutrophil and macrophage infiltration into the paws was already reduced. In addition, several inflammatory markers, including tumour necrosis factor (TNF)-α, interleukin (IL)-6 and IL-17A were reduced locally in the paws, indicating reduction of local inflammation. Furthermore, dose-setting experiments supported a beneficial clinical effect of dosing above the C5aR saturation level. In conclusion, these preclinical data demonstrated rapid onset effects of antibody blockade of C5aR. The data have translational value in supporting the Novo Nordisk clinical trials of an anti-C5aR antibody in rheumatoid arthritis patients, by identifying potential biomarkers of treatment effects as well as by providing information on pharmacodynamics and novel insights into the mechanism of action of monoclonal antibody blockade of C5aR.

Significant association between TAP2 polymorphisms and rheumatoid arthritis: a meta-analysis

Background

Rheumatoid arthritis (RA) is a severe chronic immune mediated inflammatory disease that has been shown to be associated with human leukocyte antigen (HLA) loci. The transporter associated with antigen processing 2 (TAP2) has been identified to play an important role in the HLA-associated diseases and immune response. The goal of our meta-analysis was to summarize the contribution of TAP2 polymorphisms to the risk of RA.

Methods

Meta-analyses were performed between RA and 3 TAP2 coding polymorphisms that comprised TAP2-379Ile > Val (rs1800454), TAP2-565Ala > Thr (rs2228396) and TAP2-665Thr > Ala (rs241447). The meta-analyses were involved with 9 studies (24 individual studies) among 973 cases and 965 controls.

Results

Meta-analyses showed that TAP2-379Ile allele was significantly associated with an increased risk of RA (p = 0.0002, odds ratio (OR) = 1.44, 95% confidence interval (CI) = 1.18-1.74). This association was further shown only in the dominant model (p = 0.006, OR = 1.59, 95% CI = 1.14-2.22). Subgroup analyses by ethnicity revealed that the association of TAP2-379Ile was significant in Asians (p = 0.03, OR = 1.38, 95% CI = 1.04-1.83). In addition, another significant association of TAP2-565Thr allele with RA was observed in Europeans (p = 0.002, OR = 1.62, 95% CI = 1.20-2.20).

Conclusions

Our meta-analyses suggested that TAP2-379Ile allele was significantly associated with a 59% increased risk in the dominant effect model. Subgroup analyses by ethnicity showed that TAP2-379-Ile increased the risk of RA by 38% in Asians and TAP2-565Thr increased the risk of RA by 38% in Europeans.

Virtual Slides

The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2097080313124700

Dysregulation of histone acetyltransferases and deacetylases in cardiovascular diseases

Cardiovascular disease (CVD) remains a leading cause of mortality worldwide despite advances in its prevention and management. A comprehensive understanding of factors which contribute to CVD is required in order to develop more effective treatment options. Dysregulation of epigenetic posttranscriptional modifications of histones in chromatin is thought to be associated with the pathology of many disease models, including CVD. Histone acetyltransferases (HATs) and deacetylases (HDACs) are regulators of histone lysine acetylation. Recent studies have implicated a fundamental role of reversible protein acetylation in the regulation of CVDs such as hypertension, pulmonary hypertension, diabetic cardiomyopathy, coronary artery disease, arrhythmia, and heart failure. This reversible acetylation is governed by enzymes that HATs add or HDACs remove acetyl groups respectively. New evidence has revealed that histone acetylation regulators blunt cardiovascular and related disease states in certain cellular processes including myocyte hypertrophy, apoptosis, fibrosis, oxidative stress, and inflammation. The accumulating evidence of the detrimental role of histone acetylation in cardiac disease combined with the cardioprotective role of histone acetylation regulators suggests that the use of histone acetylation regulators may serve as a novel approach to treating the millions of patients afflicted by cardiac diseases worldwide.