High serum APRIL levels strongly correlate with disease severity in pediatric atopic eczema

TNF superfamily control of tissue remodeling and fibrosis

Fibrosis is the result of extracellular matrix protein deposition and remains a leading cause of death in USA. Despite major advances in recent years, there remains an unmet need to develop therapeutic options that can effectively degrade or reverse fibrosis. The tumor necrosis super family (TNFSF) members, previously studied for their roles in inflammation and cell death, now represent attractive therapeutic targets for fibrotic diseases. In this review, we will summarize select TNFSF and their involvement in fibrosis of the lungs, the heart, the skin, the gastrointestinal tract, the kidney, and the liver. We will emphasize their direct activity on epithelial cells, fibroblasts, and smooth muscle cells. We will further report on major clinical trials targeting these ligands. Whether in isolation or in combination with other anti-TNFSF member or treatment, targeting this superfamily remains key to improve efficacy and selectivity of currently available therapies for fibrosis.

Airways therapy of obstructive sleep apnea dramatically improves aberrant levels of soluble cytokines involved in autoimmune disease

Obstructive Sleep Apnea (OSA) damages the health of 35% of adult Americans. Disordered sleep results in increased risk of several autoimmune disorders, but the molecular links to autoimmunity are poorly understood. Herein, we identified four cytokines associated with autoimmune disease, whose median serum levels were significantly different for OSA patients receiving airways therapy, from the levels in untreated OSA patients, APRIL (5.2-fold lower, p = 3.5 × 10^-11), CD30 (1.6-fold higher, p = 7.7 × 10^-5), IFN-Alpha-2 (2.9-fold higher, p = 9.6 × 10^-14) and IL-2 (1.9-fold higher, p = 0.0003). Cytokine levels in airways treated patients were similar to the levels in control subjects. t-SNE and UMAP analysis of these high dimensional patient cytokine data identified only two groups, suggesting a similar global response for all four cytokines to airways therapy. Our findings suggest the levels of these four cytokines may be altered by disordered sleep and perhaps by chronic hypoxia. Therapeutic options are discussed.

The roles of B cell activation factor (BAFF) and a proliferation-inducing ligand (APRIL) in allergic asthma

Allergic asthma, which is the most common type of asthma, is mediated by the IgE response, and B cells are key drivers of allergic inflammation in the lungs. B cell activation factor (BAFF) and proliferation inducing ligand (APRIL) are members of the TNF superfamily. BAFF and APRIL interact with three receptors, namely the B cell activation factor receptor (BAFF-r), B cell maturation antigen (BCMA), and transmembrane activator; calcium modulator; and cyclophilin ligand interactor (TACI). The interaction of BAFF and APRIL with their receptors induces B cell activation, differentiation, and antibody production. BAFF and APRIL are produced by airway epithelial cells during the response to allergens or infectious agents, and have shown to induce local IgE production, thus establishing allergic inflammation in the airways. BAFF can maintain in inflamed airways during infection and can inhibit regulatory T cells (Tregs), thereby promoting allergic inflammation in the airways. This review aims to outline current knowledge about BAFF/APRIL systems in humans as well as in murine models of allergic asthma. The precise role of BAFF and APRIL and their receptors in allergic asthma remains unclear. Therefore, further studies are required to identify and elucidate their roles in enhancing IgE production and activating immune cells that drive the Th2 effector response and initiate allergic inflammation in asthma. Targeting BAFF/APRIL or their cognate receptors may offer a novel therapeutic approach in asthma treatment.

Targeted Therapies for Autoimmune Bullous Diseases: Current Status

Autoimmune bullous skin disorders are rare but meaningful chronic inflammatory diseases, many of which had a poor or devastating prognosis prior to the advent of immunosuppressive drugs such as systemic corticosteroids, which down-regulate the immune pathogenesis in these disorders. Glucocorticoids and adjuvant immunosuppressive drugs have been of major benefit for the fast control of most of these disorders, but their long-term use is limited by major side effects such as blood cytopenia, osteoporosis, diabetes mellitus, hypertension, and gastrointestinal ulcers. In recent years, major efforts were made to identify key elements in the pathogenesis of autoimmune bullous disorders, leading to the identification of their autoantigens, which are mainly located in desmosomes (pemphigus) and the basement membrane zone (pemphigoids). In the majority of cases, immunoglobulin G, and to a lesser extent, immunoglobulin A autoantibodies directed against distinct cutaneous adhesion molecules are directly responsible for the loss of cell-cell and cell-basement membrane adhesion, which is clinically related to the formation of blisters and/or erosions of the skin and mucous membranes. We describe and discuss novel therapeutic strategies that directly interfere with the production and regulation of pathogenic autoantibodies (rituximab), their catabolism (intravenous immunoglobulins), and their presence in the circulation and extravascular tissues such as the skin (immunoadsorption), leading to a significant amelioration of disease. Moreover, we show that these novel therapies have pleiotropic effects on various proinflammatory cells and cytokines. Recent studies in bullous pemphigoid suggest that targeting of immunoglobulin E autoantibodies (omalizumab) may be also beneficial. In summary, the introduction of targeted therapies in pemphigus and pemphigoid holds major promise because of the high efficacy and fewer side effects compared with conventional global immunosuppressive therapy.