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The goblet cell-associated antigen passages (GAPs), formed in the intestine and conjunctiva, contribute to immune responses by delivering antigens to immune cells. It has been proved that dysfunctions of GAPs may contribute to intestinal inflammation and dry eye disease. GAPs were first discovered in the intestine with the help of intravital two-photon microscopy. The imaging of GAPs was subsequently captured in a frozen section and whole-mount immunofluorescent staining. Both protocols have their features. This study provides a new protocol for visualizing GAPs with better mucus preservation by combining 4% PFA and methanol-Carnoy's solution (PFA-MC). In addition, embedding samples in paraffin provides an opportunity for antigen retrieval for immunohistochemistry analysis. Using this protocol, we have successfully visualized GAPs in the intestine, intestinal organoids, conjunctiva, and trachea. It is worth mentioning that the visualization of GAPs in intestinal organoids and airways has rarely been discussed before, which may assist researchers in their studies. Moreover, we also discovered the active uptake of dextran of club cells in terminal bronchioles, which may provide a new direction for studying the function of club cells. Overall, we developed a new method to visualize GAP formation and identify GCs simultaneously in the intestine, organoid, conjunctiva, and airway.

Shufeng Jiedu capsule (SFJDC) has been widely used as a conventional Chinese pharmaceutical agent for various upper respiratory infections, including acute lung injury, acute respiratory distress syndrome and allergic rhinitis (AR). However, its mechanism in AR remains unclear.The present study aimed to decipher the antiallergic inflammatory effect of SFJDC in an AR model with olfactory dysfunction. Specifically, we wanted to explore whether SFJDC can improve the olfactory abnormality in AR mice and reduce the levels of inflammatory factors in the olfactory epithelium (OE) and olfactory bulb (OB).To address the above issues, we constructed an AR model using C57BL/6 mice, which were sensitised and challenged with ovalbumin (OVA) by intraperitoneal injection. SFJDC (0.045 or 0.18 g/kg) was delivered by gavage administration 1 h prior to the intraperitoneal injection of OVA. The control mice received saline alone. Then, the animals were assessed according to the presence of nasal symptoms and nasal inflammation, and a buried food test was used to evaluate olfactory function. The levels of proteins involved in the AMPK/mTOR autophagy pathway in the OE and OB were investigated by western blotting and fluorescence staining.After OVA induction of AR and drug administration, we found that SFJDC significantly ameliorated the nasal symptoms and allergic inflammatory reaction of the nasal mucosa superior to cetirizine. A behavioural test indicated that the mice with AR had olfactory dysfunction, and SFJDC can ameliorate this behavior deficiency. Meanwhile, SFJDC clearly reduced the neuroinflammation level in OE tissue. In addition, SFJDC increased p-mTOR and decreased p-AMPK, beclin1, LC3 and cleaved caspase-3 levels in the OE.In addition to antibacterial and antiviral activities, SFJDC has marked anti-inflammatory effects in AR mice. Its mechanism of action in the nasal cavity involves inhibition of upregulated anti-inflammatory cytokines, modulation of autophagy and apoptosis levels and regulation of autophagy through the AMPK/mTOR pathway in the OE tissue of AR mice. Hence, SFJDC is a promising drug for AR, and clinical trials should further validate the therapeutic impact of SFJDC on AR with olfactory dysfunction.