Th2 cytokines differentially regulate psoriasin expression in human nasal epithelia

Regulation of Filaggrin, Loricrin, and Involucrin by IL-4, IL-13, IL-17A, IL-22, AHR, and NRF2: Pathogenic Implications in Atopic Dermatitis

Atopic dermatitis (AD) is an eczematous, pruritic skin disorder with extensive barrier dysfunction and elevated interleukin (IL)-4 and IL-13 signatures. The barrier dysfunction correlates with the downregulation of barrier-related molecules such as filaggrin (FLG), loricrin (LOR), and involucrin (IVL). IL-4 and IL-13 potently inhibit the expression of these molecules by activating signal transducer and activator of transcription (STAT)6 and STAT3. In addition to IL-4 and IL-13, IL-22 and IL-17A are probably involved in the barrier dysfunction by inhibiting the expression of these barrier-related molecules. In contrast, natural or medicinal ligands for aryl hydrocarbon receptor (AHR) are potent upregulators of FLG, LOR, and IVL expression. As IL-4, IL-13, IL-22, and IL-17A are all capable of inducing oxidative stress, antioxidative AHR agonists such as coal tar, glyteer, and tapinarof exert particular therapeutic efficacy for AD. These antioxidative AHR ligands are known to activate an antioxidative transcription factor, nuclear factor E2-related factor 2 (NRF2). This article focuses on the mechanisms by which FLG, LOR, and IVL expression is regulated by IL-4, IL-13, IL-22, and IL-17A. The author also summarizes how AHR and NRF2 dual activators exert their beneficial effects in the treatment of AD.

T-helper 2 cytokine-induced heat shock protein 70 secretion and its potential association with allergic rhinitis

BACKGROUND

Various inflammatory mediators have been found to be involved in the pathogenesis of allergic disease (AR). The role of heat shock proteins in AR has not been studied. The aim of this study was to investigate the levels of heat shock protein 70 (Hsp70) in the nasal lavage fluids of AR patients and controls to elucidate the role of Hsp70 in the pathogenesis of AR.

METHODS

Using an enzyme-linked immunosorbent assay, the levels of Hsp70, Hsp90, interleukin (IL)-4, IL-13, and IL-8 in nasal lavage fluid from patients were measured and statistically analyzed. Primary human nasal epithelial cells were cultured in vitro and T-helper 2 (Th2) cytokines (IL-4, IL-13) were added to the culture medium. We evaluated the mRNA and protein expression levels of Hsp70 using real-time polymerase chain reaction and western blot assay.

RESULTS

Hsp70 was easily detected in nasal lavage fluid and the levels of Hsp70 were higher in AR patients than in healthy controls. Other clinical characteristics of subjects were not significantly associated with Hsp70 levels. Furthermore, we found that treatment with IL-4 and IL-13 induced the secretion of Hsp70 in human nasal epithelial cells.

CONCLUSION

We found that Hsp70 was abundant and positively detected in nasal lavage fluid samples from all subjects, and that Hsp70 levels were significantly higher in AR patients. We demonstrated, both in vivo and in vitro, that Hsp70 could play an important role in the pathogenesis of AR, and we suggest that Hsp70 can be used as a disease marker for AR.

Viruses and bacteria in Th2-biased allergic airway disease

Allergic airway diseases are typically characterized by a type 2-biased inflammation. Multiple distinct viruses and bacteria have been detected in the airways. Recently, it has been confirmed that the microbiome of allergic individuals differs from that of healthy subjects, showing a close relationship with the type 2 response in allergic airway disease. In this review, we summarize the recent findings on the prevalence of viruses and bacteria in type 2-biased airway diseases and on the mechanisms employed by viruses and bacteria in propagating type 2 responses. The understanding of the microbial composition and postinfectious immune programming is critical for the reconstruction of the normal microflora and immune status in allergic airway diseases.