What is causing my arthritis, doctor? A glimpse beyond the usual suspects in the pathogenesis of rheumatoid arthritis

Evolving cognition of the JAK-STAT signaling pathway: autoimmune disorders and cancer

The Janus kinase (JAK) signal transducer and activator of transcription (JAK-STAT) pathway is an evolutionarily conserved mechanism of transmembrane signal transduction that enables cells to communicate with the exterior environment. Various cytokines, interferons, growth factors, and other specific molecules activate JAK-STAT signaling to drive a series of physiological and pathological processes, including proliferation, metabolism, immune response, inflammation, and malignancy. Dysregulated JAK-STAT signaling and related genetic mutations are strongly associated with immune activation and cancer progression. Insights into the structures and functions of the JAK-STAT pathway have led to the development and approval of diverse drugs for the clinical treatment of diseases. Currently, drugs have been developed to mainly target the JAK-STAT pathway and are commonly divided into three subtypes: cytokine or receptor antibodies, JAK inhibitors, and STAT inhibitors. And novel agents also continue to be developed and tested in preclinical and clinical studies. The effectiveness and safety of each kind of drug also warrant further scientific trials before put into being clinical applications. Here, we review the current understanding of the fundamental composition and function of the JAK-STAT signaling pathway. We also discuss advancements in the understanding of JAK-STAT-related pathogenic mechanisms; targeted JAK-STAT therapies for various diseases, especially immune disorders, and cancers; newly developed JAK inhibitors; and current challenges and directions in the field.

Old Mice Accumulate Activated Effector CD4 T Cells Refractory to Regulatory T Cell-Induced Immunosuppression

Chronic low-grade inflammation and reduced lymphocyte potency are implicated in the pathogenesis of major illnesses associated with aging. Whether this immune phenotype results from a loss of cell-mediated regulation or intrinsic dysregulated function of effector T cells (Teffs) requires further research. Here, we report that, as compared with young C57BL6 mice, old mice show an increased frequency of CD4+CD62L- Teffs with a dysregulated activated phenotype and markedly increased effector functions. Analysis of the frequency and suppressive function of CD4+FoxP3+ regulatory T cells (Tregs) indicates an increase in the frequency of FoxP3+ T cells with aging which, however, occurs within the CD4+CD25- T cells. Furthermore, whereas Tregs from young and old mice similarly suppress Teffs from young mice, both have a compromised suppressive capacity of Teffs from old mice, a phenomenon which is partially recovered in the presence of IL-2-producing CD4+CD62L+ non-Teffs. Finally, we observed that Teff subsets from old mice are enriched with IL-17A-producing T cells and exhibit intrinsically dysregulated expression of genes encoding cell-surface molecules and transcription factors, which play a key role in T-cell activation and regulation. We, thus, demonstrate an age-related impairment in the regulation of effector CD4 T cells, which may underlie the higher risk for destructive inflammation associated with aging.

Analysis of patents on anti-rheumatoid arthritis therapies issued in China

INTRODUCTION

The etiology of rheumatoid arthritis (RA) is complex and diverse. Chronic inflammatory processes with joint dysfunction can cause permanent disability. Therefore, the development of new drugs and therapies for RA is very important.

AREAS COVERED

This review analyzes the existing patents on anti-RA products in China to help pharmaceutical companies and individuals patent potential candidate drugs for RA treatment.

EXPERT OPINION

Three hundred and seventeen patents were analyzed, including 172 patents for Traditional Chinese Medicines (TCMs, 54.2%), 65 for synthetic compounds (20.5%), 55 for biological products (17.4%) and 25 patents for the drug preparation process (7.9%). Among the TCM patents, 73.8% were of various preparations for different Chinese medicines, 23.8% were of herbal extracts and 2.3% were of herbal extract derivatives. Synthetic compounds were involved in more than 30 targets, some small-molecule drugs that target signaling kinases such as p38 MAPK, Janus kinase may become important directions in the management of RA. Biological disease-modifying antirheumatic drugs (bDMARDs) are the most efficacious drugs for RA treatment. As the classic therapeutic target in RA, TNF-α has the largest number of bDMARD patents. In addition, it is expected that new targets such as high-mobility group protein B1, thioredoxin domain-containing protein 5 (TXNDC5) and B lymphocyte stimulator (BlyS) will play a significant role in RA as potential targets for new treatments. The largest number of all the published patent applications are claiming TCMs, which may provide substantial new information for anti-RA drug development. The largest number of all the published patent applications are claiming TCMs, which may provide huge information for anti-RA drug development.