Goblet cell-associated antigen passage: A gatekeeper of the intestinal immune system

Conversion surgery after gemcitabine and cisplatin plus durvalumab for advanced intrahepatic cholangiocarcinoma: A case report

BACKGROUND

The combination of immune checkpoint inhibitors and chemotherapy has shown promising results for the treatment of advanced biliary tract cancer (BTC). Based on the results of the TOPAZ-1 trial, a gemcitabine and cisplatin plus durvalumab (GCD) regimen was recently approved as first-line therapy for patients with advanced BTC. However, post-GCD conversion surgery has not been previously studied. Herein, we describe a case of advanced intrahepatic cholangiocarcinoma (ICC) successfully treated with radical surgery after GCD.

CASE SUMMARY

A 65-year-old female diagnosed with advanced ICC with periductal infiltration into the hepatic hilum underwent eight cycles of GCD, followed by durvalumab maintenance treatment, with mild adverse events. Partial response was obtained. Subsequently, a conversion surgery with extended left hepatectomy and bile duct resection was performed. The resection margins were negative, and the pathological diagnosis was compatible with small duct type ICC. The patient remained disease-free for 8 months without adjuvant chemotherapy.

CONCLUSION

We describe the case of a patient who received successful conversion surgery after GCD treatment for advanced ICC.

Extracellular adenosine triphosphate: A new gateway for food allergy mechanism research?

Although various studies have been conducted, the detailed mechanisms of food allergy remain a topic of ongoing debate. Recently, researchers have reported that extracellular adenosine triphosphate (eATP), a member of damage-associated molecular patterns secreted by stressed cells, plays a critical role in the progression of asthma and atopic dermatitis. These studies suggest that dysregulated eATP significantly influences various aspects of disease progression, from bodily sensitization to the emergence of clinical manifestations. Given the shared pathogenic mechanisms among asthma, atopic dermatitis, and food allergies, we hypothesize that eATP may also serve as a crucial regulator in the development of food allergies. To elucidate this hypothesis, we first summarize the evidence and limitations of food allergy theories, then discuss the roles of eATP in allergic diseases. We conclude with speculative insights into the potential influence of eATP on food allergy development, aiming to inspire further investigation into the molecular mechanisms of food allergies.

PTGER4 signaling regulates class IIa HDAC function and SPINK4 mRNA levels in rectal epithelial cells

BACKGROUND

The prostaglandin receptor PTGER4 facilitates homeostasis in the gut. Previous reports indicate that goblet cells, marked by SPINK4 expression, might be affected by PTGER4 activity. Current evidence suggests that prostaglandin E2 (PGE2) produced by mesenchymal stromal cells (MSC) stimulates PTGER4 in epithelial cells during inflammatory conditions. Here, we investigate the subcellular mechanisms and mRNA levels downstream of PTGER4 activity in epithelial cells.

METHODS

Mucosal cells, organoids, and MSC were obtained from patient biopsies harvested by endoscopy. Using independent and co-cultures, we manipulated the activity of PTGER4, the downstream enzymes, and mRNA levels, by using PGE2, in combination with chemical inhibitors, L-161982, H89, LB100, DAPT, LMK-235, or with butyrate. Immunofluorescence, single cell sequencing, RNAscope, ELISA, real time PCR, and Western blotting were used to examine these samples.

RESULTS

SPINK4 mRNA levels were increased in organoids by co-culture with MSC or exogenous stimulation with PGE2 that could be blocked by L-161982 or LMK-235, PTGER4 or HDAC4 inhibitors, respectively. Expression of PTGER4 was co-localized with JAM-A in the basolateral surfaces in rectal epithelial cells grown as organoids. PGE2 treatment of rectal organoids decreased HDAC4, 5, and 7 phosphorylation levels that could be blocked by L-161982 treatment. Butyrate treatment, or addition of L-161982, increased the phosphorylated levels of HDAC4, 5, and 7.

CONCLUSIONS

These findings suggest a mechanism during mucosal injury whereby MSC production of PGE2 increases HDAC4, 5, and 7 activities in epithelial cells by upregulating PTGER4 signaling, ultimately increasing SPINK4 mRNA levels and extracellular release of SPINK4.

Investigating tributyltin's toxic effects: Intestinal barrier and neuroenteric disruption in rat's jejunum

The expansion of economic activities in coastal areas has significantly increased chemical contamination, leading to major environmental challenges. Contaminants enter the human body through the food chain, particularly via seafood and water consumption, triggering biomagnification and bioaccumulation processes. The gastrointestinal tract (GIT) acts as a selective barrier, protecting against chemical pollutants and maintaining homeostasis through a complex network of cells and immune responses. This study assessed impact of tributyltin (TBT), a highly toxic organometallic compound used in antifouling coatings for ships, on the GIT and myenteric neural plasticity in young rats. TBT exposure leads to histopathological changes, including epithelial detachment and inflammatory foci, especially at lower environmental doses. The study found that TBT causes significant reductions in villi height, increases in goblet cells and intraepithelial lymphocytes, and disrupts the myenteric plexus, with higher densities of extraganglionic neurons in exposed animals.

Extracellular adenosine triphosphate skews the T helper cell balance and enhances neutrophil activation in mice with food allergies

Exposure to food allergens elicits fast changes in the intestinal microenvironment, which guides the development of allergic reactions. Investigating the key information about these changes may help in better understanding food allergies. In this research, we explored the relationship between a food allergy and extracellular adenosine triphosphate (ATP), a danger molecule that has been proved to regulate the onset of allergic asthma and dermatitis but has not been studied in food allergies, by developing a unique animal model through allergen-containing diet feeding. After consuming an allergen-containing diet for 7 days, the allergic mice exhibited severe enteritis with elevated luminal ATP levels. The dysregulated luminal ATP worsened food-induced enteritis by enhancing Th17 cell responses and increasing mucosal neutrophil accumulation. In vitro experiments demonstrated that ATP intervention facilitated Th17 cell differentiation and neutrophil activation. In addition, the diet-induced allergy showed noticeable gut dysbiosis, characterized by decreased microbial diversity and increased diet-specific microbiota signatures. As the first, we show that food-induced enteritis is associated with an elevated concentration of luminal ATP. The dysregulated extracellular ATP exacerbated the enteritis of mice to a food challenge by manipulating intestinal Th17 cells and neutrophils.

Early-life microbiota-immune homeostasis

As the prevalence of allergy and autoimmune disease in industrialized societies continues to rise, improving our understanding of the mechanistic roles behind microbiota-immune homeostasis has become critical for informing therapeutic interventions in cases of dysbiosis. Of particular importance, are alterations to intestinal microbiota occurring within the critical neonatal window, during which the immune system is highly vulnerable to environmental exposures. This review will highlight recent literature concerning mechanisms of early-life microbiota-immune homeostasis as well as discuss the potential for therapeutics in restoring dysbiosis in early life.