Bifidobacterium breve (B. breve) may have a beneficial effect on allergic rhinitis (AR). The aim of the present study was to investigate whether microbial induction of regulatory T cells (Tregs) and adjustment of Th1 and Th2 responses by B. breve are associated with protection against allergic inflammation, and to identify a dose-response association in a murine AR model. Ovalbumin (OVA)-sensitized BALB/c mice were orally treated with different doses of B. breve [1010, 109, 107 and 105 colony forming units (CFU)]. Following nasal challenge with OVA, sneeze frequency, serum OVA-specific immunoglobulin E (IgE) and cytokine concentrations [interleukin (IL)-4, IL-10, IL-13 and interferon-γ], splenic percentage of cluster of differentiation (CD)4+CD25+ Tregs, and morphology of the nasal mucosa were examined. Oral treatment with live B. breve at doses of 107 CFU or higher alleviated nasal mucosal injury and suppressed sneezing upon repeated administration over a 6-week period. Furthermore, treatment with B. breve at these higher doses reduced the concentrations of serum OVA-specific IgE, IL-4 and IL-10, and increased the splenic percentage of CD4+CD25+ Tregs in rhinitic mice compared with those who did not receive probiotics. In contrast, treatment with B. breve at a lower dose did not indicate any effect on sneezing frequency or mucosal morphology in this animal model, even though the splenic percentage of CD4+CD25+ Tregs increased and the concentrations of serum OVA-specific IgE and IL-10 declined. B. breve exerts its anti-allergic effects by inhibiting type 2 helper T cell immune responses and enhancing CD4+CD25+ Treg activity. Sneezing was also reduced at a dose of 107 CFU or higher. The current study investigated the role of B. breve and aided in identifying the optimal dose of B. breve administration in the treatment of AR.

The AMC-HN-8 cell line and the primary human laryngeal epi-thelial cell lines were utilized in this work to explore the molecular mecha-nism of miR-548-3p regulating the gene DAG1 to induce the occurrence and malignant transformation of laryngeal carcinoma. Non-coding RNA miR-548-3p overexpression plasmid, interference plasmid and blank plasmid were con-structed, and the plasmids were transfected into AMC-HN-8 cells, respectively. Meanwhile, a non-transfected plasmid group and a human laryngeal epithelial primary cell group were set up. Five groups of cells were named as NC (Nor-mal control), Model, Ov-miR-548-3p, Sh-miR-548-3p and Blank-plasmid group. The luciferase reporter experiment was used to analyze the regulation charac-teristics of hsa-miR-548-3p on dystrophin-associated glycoprotein 1 (DAG1). Immunofluorescence was used to analyze the relative expression characteris-tics of the protein DAG1. The cell cloning experiment was used to analyze the proliferation characteristics of AMC-HN-8. The scratch healing test was used to analyze the migration ability of AMC-HN-8. The transwell test was used to analyze the invasion ability of AMC-HN-8. The RT-PCR was used to analyze the expression level of miR-548-3p. Western blot experiments were used to analyze the expression of protein DAG1, laminin α2 (LAMA2) and utrophin (UTRN). The luciferase report experiment and immunofluorescence test found that the expression of DAG1 and miR-548-3p are positively correlated. Cell cloning, scratching and migration experiments identified that the activity of laryngeal cancer cells was positively correlated with the expression of DAG1. The results of Western blot analysis further strengthened the above conclusions. Through carrying out research on the cellular levels, our work has demonstrated that miR-548-3p regulated the content of protein DAG1, and then further induced malignant transformation of laryngeal carcinoma.

Background Tympanic membrane perforation (TMP) is a common disease in otology, and few acellular techniques have been reported for repairing this condition. Decellularized extracellular matrix (ECM) scaffolds have been used in organ reconstruction. Objective This study on tissue engineering aimed to develop a tympanic membrane (TM) scaffold prepared using detergent immersion and bone marrow mesenchymal stem cells (BMSCs) as repair materials to reconstruct the TM. Results General structure was observed that the decellularized TM scaffold with BMSCs retained the original intact anatomical ECM structure, with no cell residue, as observed using scanning electron microscopy (SEM), and exhibited low immunogenicity. Therefore, we seeded the decellularized TM scaffold with BMSCs for recellularization. Histology and eosin staining, SEM and immunofluorescence in vivo showed that the recellularized TM patch had a natural ultrastructure and was suitable for the migration and proliferation of BMSCs. The auditory brainstem response (ABR) evaluated after recellularized TM patch repair was slightly higher than that of the normal TM, but the difference was not significant. Conclusion The synthetic ECM scaffold provides temporary physical support for the three‐dimensional growth of cells during the tissue developmental stage. The scaffold stimulates cells to secrete their own ECM required for tissue regeneration. The recellularized TM patch shows potential as a natural, ultrastructure biological material for TM reconstruction.