Objective To identify the cross-reactive antigens shared by Mycobacteria smegmatis(MS) and Mycobacteria tuberculosis(MTB) and to analyze their antigenicity.Methods Bacterial antigens were extracted from strains of MS and MTB by ultrasonication.Western blot assay was performed to analyze common antigens that reacted with both of the antiserum samples against MS and MTB.The extracted bacterial antigens were mixed with incomplete Freund′s adjuvant and then were injected into muscles of mice.Cytokines secreted by murine spleen lymphocytes following stimulation with various antigens of MS and MTB were determined by ELISPOT and flow cytometry on the 7th day.IgG levels in serum samples were detected by ELISA 7 days after injection.Results There were cross-reactive antigens shared by MS and MTB.Potent humoral immune responses and cellular immunity against both MS and MTB could be induced by those cross-reactive antigens after sensitization the mice by either MS or MTB antigens.Cytokines of IL-2 and IFN-γ in CD4+ and CD8+T cells of mice stimulated with MS or MTB antigens were significantly increased as compared with those of non-sensitization group and those of Brucella antigens stimulation group.ConclusionCross-reactive antigens shared by MS and MTS can effectively promote specific immune reactions to the infection of MTB, which provides a scientific basis for the development of tuberculosis vaccines.

Objective: To investigate the specificity of endogenous metabolic profile in plasma of patients with occupational acute methyl acetate poisoning using non-targeted metabolomics. Methods: A total of six patients with occupational acute methyl acetate poisoning were selected as the poisoning group, while 10 healthy workers without occupational exposure history of chemical hazards in the same industry were selected as the control group using the judgment sampling method. Metabolites in patient plasma of the two groups were detected using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry, and non-targeted metabolomics analysis was performed. Principal component analysis and partial least squares discriminant analysis were used to identify differential metabolites and analyze their metabolic pathways. Results: There were significant differences in metabolite profiles in patient plasma between poisoning group and control group. A total of 195 differentially expressed metabolites were screened in plasma of patients in poisoning group, including 119 upregulated and 76 downregulated metabolites. Lipid substances (lipids and lipid-like molecules) accounted for the highest proportion (21.5%). The differential metabolites of poisoning group were related to folate biosynthesis, amino acid metabolism, pyrimidine metabolism, sphingolipid biosynthesis and other metabolic pathways in plasma compared with the control group (all P<0.05). Conclusion: Occupational acute methyl acetate poisoning affects metabolism of the body. The folic acid biosynthesis, amino acid and lipid metabolism and other pathways may be involved in the occurrence and development of poisoning.

Objective: To explore an optimal method for granulocyte cell production from umbilical cord blood mononuclear cells. Methods: Erythrocytes were precipitated by hydroxyethyl starch. Mononuclear cells were isolated through Ficoll density gradient centrifugation. Different media, additives and cultivation model were chosen for granulocyte induction. Cell morphology was observed by microscopy, and cell phenotype was detected by flow cytometry. The CD18 expression of granulocytes was tested by immunofluorescence assay, and phagocytosis test was executed as well. Results: Compared to fetal bovine serum (FBS) treatment group, cell viability, counts and differentiation rate of granulocytes induced by X-VIVO^TM 15 combined with TPO, SCF, G-CSF but without FBS were superior. And X-VIVO^TM15 medium was better than SCGM medium at effectiveness and cost. Using two-stage mode of hematopoietic stem cell expansion followed by granulocyte induction with X-VIVO^TM15 combining TPO, SCF and G-CSF, cell proliferation was nearly 132 times at day 21. Flow cytometry showed that the differentiation was lagged in 2-stage mode than in direct induction mode, CD15 expression was (69.60± 1.06) % vs (97.73±0.39) %; Wright-Giemsa staining demonstrated mature granulocytes; immunofluorescence showed the expression of lysosomal proteins CD18. A strong phagocytic function of mature granulocytes was demonstrated by phagotrophic efficiency of (51.43±0.05) %. And granulocyte had chemotaxis ability under the role of chemotactic factor IL-8. Conclusion Optimized culture media and cultivation mode are achieved for functional granulocytes induction in vitro.