Altered Differentiation and Inflammation Profiles Contribute to Enhanced Innate Responses in Severe COPD Epithelium to Rhinovirus Infection

Thymic Stromal Lymphopoietin and Tezepelumab in Airway Diseases: From Physiological Role to Target Therapy

Thymic stromal lymphopoietin (TSLP), is a protein belonging to a class of epithelial cytokines commonly called alarmins, which also includes IL-25 and IL-33. Functionally, TSLP is a key player in the immune response to environmental insults, initiating a number of downstream inflammatory pathways. TSLP performs its role by binding to a high-affinity heteromeric complex composed of the thymic stromal lymphopoietin receptor (TSLPR) chain and IL-7Rα. In recent years, the important role of proinflammatory cytokines in the etiopathogenesis of various chronic diseases such as asthma, chronic rhinosinusitis with nasal polyposis (CRSwNP), chronic obstructive pulmonary diseases (COPDs), and chronic spontaneous urticaria has been studied. Although alarmins have been found to be mainly implicated in the mechanisms of type 2 inflammation, studies on monoclonal antibodies against TSLP demonstrate partial efficacy even in patients whose inflammation is not definable as T2 and the so-called low T2. Tezepelumab is a human anti-TSLP antibody that prevents TSLP-TSLPR interactions. Several clinical trials are evaluating the safety and efficacy of Tezepelumab in various inflammatory disorders. In this review, we will highlight major recent advances in understanding the functional role of TSLP, its involvement in Th2-related diseases, and its suitability as a target for biological therapies.

Interferon lambda in respiratory viral infection: immunomodulatory functions and antiviral effects in epithelium

Type III interferon (IFN-λ), a new member of the IFN family, was initially considered to possess antiviral functions similar to those of type I interferon, both of which are induced via the JAK/STAT pathway. Nevertheless, recent findings demonstrated that IFN-λ exerts a nonredundant antiviral function at the mucosal surface, preferentially produced in epithelial cells in contrast to type I interferon, and its function cannot be replaced by type I interferon. This review summarizes recent studies showing that IFN-λ inhibits the spread of viruses from the cell surface to the body. Further studies have found that the role of IFN-λ is not only limited to the abovementioned functions, but it can also can exert direct and/or indirect effects on immune cells in virus-induced inflammation. This review focuses on the antiviral activity of IFN-λ in the mucosal epithelial cells and its action on immune cells and summarizes the pathways by which IFN-λ exerts its action and differentiates it from other interferons in terms of mechanism. Finally, we conclude that IFN-λ is a potent epidermal antiviral factor that enhances the respiratory mucosal immune response and has excellent therapeutic potential in combating respiratory viral infections.

Intestinal barrier dysfunction induced by ammonia exposure in pigs in vivo and in vitro: The protective role of L-selenomethionine

Ammonia has been reported to have a variety of toxicity to aquatic animals, farm animals and humans. However, its potential toxicity on the intestines remains unknown. L-selenomethionine is one of the important organic selenium sources. However, the mitigating effect of L-selenomethionine on ammonia exposure toxicity is still lacking. Therefore, in this study, the mechanism of toxic action of ammonia on intestinal tract and the detoxification effect of L-selenomethionine were examined. We evaluated the intestinal toxicity of ammonia and the alleviating effect of L-selenomethionine in an in vivo model, and then verified it in vitro model by a variety of cutting-edge experimental techniques. Our results showed that ammonia exposure causes oxidative stress, necroptosis, Th1/Th2 imbalance and inflammation in the intestinal tissue and the intestinal cells, and L-selenomethionine had a significant mitigation effect on the changes of these indexes induced by ammonia. In conclusion, ammonia exposure caused oxidative stress and Th1/Th2 imbalance in the porcine small intestine and IPEC-J2 cells, and that excessive ROS accumulation-mediated necroptosis targeted inflammatory responses, resulting in the destruction of tight connections of intestinal cells, thereby causing intestinal barrier dysfunction. L-selenomethionine could effectively reduce the intestinal injury caused by ammonia exposure and antagonize the toxic effect of ammonia.