Transcriptome Analysis Identifies Oxidative Stress Injury Biomarkers for Diabetic Nephropathy.

BACKGROUND: The early diagnosis of diabetic nephropathy (DN) is essential for improving the prognosis and effectively manage patients affected with this disease. The standard biomarkers, including albuminuria and glomerular filtration rate, are not very precise. New molecular biomarkers are needed to more accurately identify DN and better predict disease progression. Characteristic DN biomarkers can be identified using transcriptomic analysis. AIM OF THE STUDY: To evaluate the transcriptomic profile of controls (CTRLs, n = 15), patients with prediabetes (PREDM, n = 15), patients with type-2 diabetes mellitus (DM2, n = 15), and patients with DN (n = 15) by microarray analysis to find new biomarkers. RT-PCR was then used to confirm gene biomarkers specific for DN. MATERIALS AND METHODS: Blood samples were used to isolate RNA for microarray expression analysis. 26,803 unique gene sequences and 30,606 LncRNA sequences were evaluated-Selected gene biomarkers for DN were validated using qPCR assays. Sensitivity, specificity, and area under the curve (AUC) were calculated as measures of diagnostic accuracy. RESULTS: The DN transcriptome was composed of 300 induced genes, compared to CTRLs, PREDM, and DM-2 groups. RT-qPCR assays validated that METLL22, PFKL, CCNB1 and CASP2 genes were induced in the DN group compared to CTRLs, PREDM, and DM-2 groups. The ROC analysis for these four genes showed 0.9719, 0.8853, 0.8533 and 0.7748 AUC values, respectively. CONCLUSION: Among induced genes in the DN group, we found that CASP2, PFKL and CCNB1 may potentially be used as biomarkers to diagnose DN. Of these, METLL22 had the highest AUC score, at 0.9719.

The use of Streptomyces for immunization against mycobacterial infections.

Tuberculosis is one of the leading causes of mortality produced by an infectious agent. Different strategies including bioinformatics are currently being tested to identify and improve vaccines against tuberculosis. Comparative genome analysis between Streptomyces coelicolor and Mycobacterium tuberculosis suggest that both descend from a common Actinomycete ancestor. In this work, we suggest the use of Streptomyces as a live vector and explore the capacity of Streptomyces immunization to induce a protective response against mycobacterial infection. First, we compared the theoretical proteomes of S. coelicolor A3(2) with those of M. tuberculosis H37Rv and Mycobacterium bovis AF2122/97. This study showed a high similarity at the level of individual genes sequences with both bacteria sharing several membrane proteins. Then, we administered Streptomyces intraperitoneally to mice and determined its distribution by histopathology and culture; we did not find systemic dissemination. After administration of Streptomyces through different routes, we identified the most immunogenic, inducing strong humoral response, as denoted by the high serum antibody titers against this organism with cross reactivity to mycobacterial antigens. Finally, we evaluated the level of protection elicited by the inoculation of Streptomyces in Balb/c mice challenged with BCG. In these animals, lung bacillary loads were significantly lower than the control non-sensitized group.. These observations, along with Streptomyces' potential for expressing foreign proteins, suggest that Streptomyces could be an advantageous vector in the design of new tuberculosis vaccines.

Immunization of mice with a Mycobacterium tuberculosis genomic expression library results in lower bacterial load in lungs after challenge with BCG.

Tuberculosis is a serious infectious disease in many developing countries. The lack of an effective vaccine for preventing this disease has stimulated the search for new vaccine candidates against Mycobacterium tuberculosis. In the present work, the construction of a genomic expression library of M. tuberculosis in a eukaryotic expression vector was carried out. Immunization of Balb/c mice with a plasmid DNA pool from this library (containing 8360 clones) induced a significant IgG antibody response. Immunized mice were challenged by intratracheal route with 10(5) cfu of non-pathogenic Mycobacterium bovis BCG and were sacrificed 21 days post-challenge. Mice immunized with the genomic expression library showed a significant reduction of viable bacteria in lungs and less pulmonary tissue damage. Granulomas were not observed and the lungs had a more discrete perivascular inflammatory cell infiltrate compared to control mice. Results suggest that the genomic expression library contains genes encoding proteins that are protective against M. tuberculosis infection.