CXCL13 is a chemokine that is widely involved in the pathogenesis of autoimmune diseases, tumors and inflammatory diseases. In this study, we investigate the role of CXCL13 in the pathogenesis of inflammatory bowel disease using both clinical specimens and animal models. We found that the serum CXCL13 concentration in IBD patients was significantly higher than that in healthy controls, and correlated with that of CRP, neutrophils counts and hemoglobin. The increase of CXCL13 in IBD patients might be related to the significant decrease of circulating CD4+CXCR5+ T cells, the increase of CD19+CD5+ B cells and the enhancement of humoral immunity. In mice colitis model, we also found elevated levels of CXCL13 in colon tissue. Cxcl13^-/- knockout mice exhibited a mild, self-limiting form of disease. Additionally, CXCL13 deficiency restricted CD4+CXCR5+ T cells migration in mesenteric lymph nodes, resulting locally regulatory B cells increased in colon. In conclusion, our findings raise the possibility that CXCL13 plays a critical role in the pathogenesis of IBD. We believe that our findings will contribute to the understanding of the etiology, and that antagonizing or inhibiting CXCL13 may work as a potential adjunctive therapy strategy for patients with IBD.

Background: This case report presents a 12-year-old male with vertically transmitted chronic hepatitis B virus (HBV) infection, exhibiting a rare pan-reactive serological profile (concurrent HBsAg, HBsAb, HBeAg, HBeAb, and HBcAb positivity) alongside fluctuating low-level viremia (HBV DNA: 1.06 × 10² IU/mL to undetectable). Rigorous exclusion of technical artifacts confirmed the authenticity of this atypical serologic pattern, observed in <0.001% of the general population. Methods: Liver biopsy and immunohistochemical staining were performed to evaluate hepatic inflammation and fibrosis. HBV serological markers and viral load were quantified using commercial diagnostic kits, with longitudinal monitoring for 18 months. Results: Liver biopsy revealed Grade 2 inflammation with focal HBsAg/HBcAg expression, supporting immune-active chronic hepatitis B (CHB) despite partial seroconversion. The patient’s clinical course highlights key challenges in pediatric HBV management: (1) delayed immune reconstitution (18-month longitudinal HBeAg/HBeAb dynamics), (2) non-linear virologic-ALT correlation, and (3) diagnostic ambiguity in pan-positive serology—potentially reflecting S-gene escape mutants or transitional immune responses. Initiation of tenofovir disoproxil fumarate (TDF) achieved sustained virologic suppression, underscoring the importance of early antiviral therapy in pediatric CHB with atypical markers. Conclusions: This case provides preliminary insights into the complex interplay between viral evolution and immature host immunity, advocating for refined monitoring protocols integrating high-sensitivity HBV DNA, quantitative serology, and non-invasive fibrosis assessment in pediatric HBV care.

Background/Objectives: As an escalating global health challenge, food allergies impose substantial burdens on the physical and psychological well-being of pediatric populations, profoundly compromising their quality of life. Given the marked geographical heterogeneity in allergen distribution patterns, this epidemiological investigation systematically characterizes prevalent pediatric food allergens sensitization patterns in Southwest China, yielding critical region-specific data to inform targeted prevention strategies and clinical management protocols. Methods: A cohort of 36,399 pediatric participants (age <18 years) underwent hospital-based testing for allergen-specific immunoglobulin E (sIgE) reactivity against 10 regionally prevalent food allergens, utilizing a semi-quantitative, immunocapture-based, and enzyme-linked immunosorbent assay. Results: Of the 36,399 children whose food allergen sensitization profiles were analyzed, 48.12% (n = 17,514) demonstrated elevated sIgE reactivity in response to at least one tested allergen, with milk and eggs emerging as the predominant allergenic triggers. Age-stratified analyses identified preschool age (≤6 years) as the critical window for food sensitization, demonstrating peak IgE reactivity to major allergens, including milk, peanuts, soybeans, shrimp, eggs, wheat, and beef. Male subjects exhibited significantly higher sensitization rates to peanuts, soybeans, crustaceans and wheat compared to females (p < 0.05), underscoring the importance of sex-based considerations in allergy prevention strategies. Conclusions: Milk and eggs emerge as the dominant food allergens that cause sensitization in Chengdu’s pediatric population. Age- and sex-dependent vulnerabilities were identified, with younger children and male participants demonstrating higher sensitization rates than their counterparts. These age-stratified and male-predominant sensitization patterns provide a scientific foundation for public health initiatives.