Little is known about the regulatory effect of microbiota on the proliferation and regeneration of ISCs. Here, we found that L. reuteri stimulated the proliferation of intestinal epithelia by increasing the expression of R-spondins and thus activating the Wnt/β-catenin pathway. The proliferationstimulating effect of Lactobacillus on repair is further enhanced under TNF -induced intestinal mucosal damage, and the number of Lgr5 + cells is maintained. Moreover, compared to the effects of C. rodentium on the induction of intestinal inflammation and crypt hyperplasia in mice, L. reuteri protected the intestinal mucosal barrier integrity by moderately modulating the Wnt/β-catenin signaling pathway to avoid overactivation. L. reuteri had the ability to maintain the number of Lgr5 + cells and stimulate intestinal epithelial proliferation to repair epithelial damage and reduce proinflammatory cytokine secretion in the intestine and the LPS concentration in serum. Moreover, activation of the Wnt/β-catenin pathway also induced differentiation toward Paneth cells and increased antimicrobial peptide expression to inhibit C. rodentium colonization. The protective effect of Lactobacillus against C. rodentium infection disappeared upon application of the Wnt antagonist Wnt-C59 in both mice and intestinal organoids. This study demonstrates that Lactobacillus is effective at maintaining intestinal epithelial regeneration and homeostasis as well as at repairing intestinal damage after pathological injury and is thus a promising alternative therapeutic method for intestinal inflammation.

In this study, we demonstrate that tumor-derived exosome-loaded dendritic cells can elicit a specific CD8(+) cytotoxic T-lymphocyte (CTL) response against autologous tumor cells in patients with malignant glioma. Exosomes were purified by ultrafiltration centrifugation and sucrose gradient ultracentrifugation. Exosomes had antigen-presenting molecules (MHC-I, HSP70), tumor antigen (MAGE-1) and adherent molecule (ICAM-1). After incubation with exosomes, the dendritic cells (DCs) could activate the T lymphocytes to become glioma-specialized CTL. The CTL had vigorous cytotoxicity to glioma cells as opposed to autologous lymphoblast cells. These data demonstrate that tumor exosome-loaded DC can be an effective tool in inducing glioma-specific CD8(+) CTLs able to kill autologous glioma cells in vitro. In conclusion, exosomes are a natural and new source of tumor-rejection antigens, opening up new avenues for immunization against glioma.

No abstract

The study demonstrates that colitis improvement is controlled by Lactobacillus ATCC 4356 by regulation of the Notch pathway; this finding will be useful for prevention against animal S. typhimurium infection.

Chaperone-rich cell lysates (CRCLs) may play an important role in the development of anti-tumor vaccines. Tumor-derived CRCLs have been reported to activate dendritic cells (DCs) to elicit potent anti-tumor activity. However, the role of DC-derived exosomes (DEXs) secreted from DCs loaded with CRCLs in the treatment of tumors has not been clearly determined. In the present study, DEXs were generated from DCs loaded with CRCLs derived from GL261 glioma cells. These DEXs, designated DEX (CRCL-GL261), were then used to treat DCs to create DEX (CRCL-GL261)-DCs. The DEX (CRCL-GL261)-DCs were found to promote cell proliferation and cytotoxic T lymphocyte (CTL) activity of CD4(+) and CD8(+) T cells in vitro compared with DEX (GL261)-DCs, which were loaded with DEXs derived from DCs loaded with GL261 tumor cell lysates. DEX (CRCL-GL261)-DCs significantly prolonged the survival of mice with tumors and inhibited tumor growth in vivo. In addition, DEX (CRCL-GL261)-DCs induced enhanced T cell infiltration in intracranial glioma tissues compared with other treatments. DEX (CRCL-GL261)-DCs induced strong production of anti-tumor cytokines, including interleukin-2 and interferon-γ. Moreover, depletion of CD4(+) and CD8(+) T cells significantly impaired the anti-tumor effect of DEX (CRCL-GL261)-DCs. Finally, DEX (CRCL-GL261)-DCs were found to negatively regulate Casitas B cell lineage lymphoma (Cbl)-b and c-Cbl signaling, leading to the activation of phosphatidyl inositol 3-kinase (PI3K)/Akt and extracellular signal-regulated kinase (ERK) signaling in T cells. In summary, we present evidence that DEX (CRCL-GL261)-DCs induce more potent and effective anti-tumor T cell immune responses and delineate the underlying mechanism by which DEX (CRCL-GL261)-DCs exerted their anti-tumor activity through modulating Cbl-b and c-Cbl signaling. These results provide novel and promising insight for the development of an anti-tumor vaccine.

Rationale: Early diagnosis and treatment of tuberculous meningitis saves lives, but current laboratory diagnostic tests lack sensitivity.Objectives: We investigated whether the detection of intracellular bacteria by a modified Ziehl-Neelsen stain and early secretory antigen target (ESAT)-6 in cerebrospinal fluid leukocytes improves tuberculous meningitis diagnosis.Methods: Cerebrospinal fluid specimens from patients with suspected tuberculous meningitis were stained by conventional Ziehl-Neelsen stain, a modified Ziehl-Neelsen stain involving cytospin slides with Triton processing, and an ESAT-6 immunocytochemical stain. Acid-fast bacteria and ESAT-6-expressing leukocytes were detected by microscopy. All tests were performed prospectively in a central laboratory by experienced technicians masked to the patients' final diagnosis.Measurements and Main Results: Two hundred and eighty patients with suspected tuberculous meningitis were enrolled.Thirty-seven had Mycobacterium tuberculosis cultured from cerebrospinal fluid; 40 had a microbiologically confirmed alternative diagnosis; the rest had probable or possible tuberculous meningitis according to published criteria. Against a clinical diagnostic gold standard the sensitivity of conventional Ziehl-Neelsen stain was 3.3% (95% confidence interval, 1.6-6.7%), compared with 82.9% (95% confidence interval, 77.4-87.3%) for modified Ziehl-Neelsen stain and 75.1% (95% confidence interval, 68.8-80.6%) for ESAT-6 immunostain. Intracellular bacteria were seen in 87.8% of the slides positive by the modified Ziehl-Neelsen stain. The specificity of modified Ziehl-Neelsen and ESAT-6 stain was 85.0% (95% confidence interval, 69.4-93.8%) and 90.0% (95% confidence interval, 75.4-96.7%), respectively.Conclusions: Enhanced bacterial detection by simple modification of the Ziehl-Neelsen stain and an ESAT-6 intracellular stain improve the laboratory diagnosis of tuberculous meningitis.

No abstract

Erythropoietin (EPO) may protect the nervous system of animals against aging damage, making it a potential anti-aging drug for the nervous system. However, experimental evidence from natural aging nerve cell models is lacking, and the efficacy of EPO and underlying mechanism of this effect warrant further study. Thus, the present study used long-term cultured primary nerve cells to successfully mimic the natural aging process of nerve cells. Starting on the 11th day of culture, cells were treated with different concentrations of recombinant human erythropoietin (rhEPO). Using double immunofluorescence labeling, we found that rhEPO significantly improved the morphology of long-term cultured primary nerve cells and increased the total number of long-term cultured primary cells. However, rhEPO did not improve the ratio of nerve cells. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was used to measure nerve cell activity and showed that rhEPO significantly improved the activity of long-term cultured primary nerve cells. Moreover, Annexin V-fluorescein isothiocyanate (FITC)/propidium iodide (PI) double immunofluorescence labeling flow cytometry revealed that rhEPO reduced the apoptotic rate of long-term cultured primary nerve cells. Senescence-associated β-galactosidase (SA-β-gal) immunohistochemistry staining showed that rhEPO significantly reduced the aging rate of long-term cultured primary nerve cells. Immunochemistry revealed that rhEPO enhanced intracellular superoxide dismutase (SOD) activity and glutathione (GSH) abundance and reduced the intracellular malondialdehyde (MDA) level. In addition, this effect depended on the dose, was maximized at a dose of 100 U/ml and was more pronounced than that of vitamin E. In summary, this study finds that rhEPO protects long-term cultured primary nerve cells from aging in a dose-dependent manner. The mechanism of this effect may be associated with the enhancement of the intracellular anti-oxidant capacity. These findings provide a theoretical basis to further the anti-aging mechanism of EPO in the nervous system, and they provide experimental evidence at the cellular level for the clinical application of EPO to protect the nervous system from aging.