Multi-Functional MPT Protein as a Therapeutic Agent against Mycobacterium tuberculosis

Colon-Targeted eNAMPT-Specific Peptide Systems for Treatment of DSS-Induced Acute and Chronic Colitis in Mouse

Nicotinamide phosphoribosyl transferase (NAMPT) is required to maintain the NAD⁺ pool, among which extracellular (e) NAMPT is associated with inflammation, mainly mediated by macrophages. However, the role of (e) NAMPT in inflammatory macrophages in ulcerative colitis is insufficiently understood. Here our analyses of single-cell RNA-seq data revealed that the levels of NAMPT and CYBB/NOX2 in macrophages were elevated in patients with colitis and in mouse models of acute and chronic colitis. These findings indicate the clinical significance of NAMPT and CYBB in colitis. Further, we found that eNAMPT directly binds the extracellular domains of CYBB and TLR4 in activated NLRP3 inflammasomes. Moreover, we developed a recombinant 12-residue TK peptide designated colon-targeted (CT)-conjugated multifunctional NAMPT (rCT-NAMPT), comprising CT as the colon-targeting moiety, which harbors the minimal essential residues required for CYBB/TLR4 binding. rCT-NAMPT effectively suppressed the severity of disease in DSS-induced acute and chronic colitis models through targeting the colon and inhibiting the interaction of NAMPT with CYBB or TLR4. Together, our data show that rCT-NAMPT may serve as an effective novel candidate therapeutic for colitis by modulating the NLRP3 inflammasome-mediated immune signaling system.

Expression and epitope prediction of MPT64 recombinant proteins from clinical isolates of Mycobacterium tuberculosis as immunoserodiagnostic candidates

Background and Aim: The success in the handling and prevention of tuberculosis (TB) cases is highly dependent on their rapid detection, monitoring, and treatment. The efficacy of the Bacille Calmette–Guerin (BCG) vaccine is inconclusive in eastern Indonesia. The RV1980c gene of Mycobacterium tuberculosis encodes an antigenic protein that is considered to be a virulence factor, as it can stimulate the immune response in patients with TB. This study aimed to study the expression and epitope indicator of MPT64 recombinant proteins from clinical isolates of M. tuberculosis as immunoserodiagnostic candidates for pET SUMO plasmids from clinical isolates as candidates for serodiagnostic tests and recombinant vaccines. Materials and Methods: The polymerase chain reaction (PCR) product of the RV1980c gene was inserted into the SUMO pET plasmid, which was then transformed into Escherichia coli BL21 (DE3) cells and expressed in Luria Bertani media induced by 1.0 M IPTG. Subsequently, sequencing was performed and the results were analyzed using the ClustalW and National Center for Biotechnology Information BLAST software. The T-cell epitope prognosis was then explained by GENETYX version 8.0., for the prediction of B-cell epitope, as assessed using an Immune Epitope Database analysis. Results: The PCR product of the RV1980c gene had a length of 619 bp. Moreover, SDS–polyacrylamide gel electrophoresis and Western blotting revealed that the protein encoded by the Rv1980c gene weighed 36 kDa. We gained nine specific T-cell epitopes according to Iad Pattern position and eight epitopes according to Rothbard/Taylor Pattern Position; furthermore, we detected five B-cell epitopes in the RV1980c gene. Conclusion: The MPT64 protein encoded by the RV1980c gene carries epitopes that are realized by lymphocytes and represent potential immunoserodiagnostic candidates in diagnostic immunology.

Discovery of Mycobacterium tuberculosis Rv3364c-Derived Small Molecules as Potential Therapeutic Agents to Target SNX9 for Sepsis

The serine protease inhibitor Rv3364c of Mycobacterium tuberculosis (MTB) is highly expressed in cells during MTB exposure. In this study, we showed that the ₁₂WLVSKF₁₇ motif of Rv3364c interacts with the BAR domain of SNX9 and inhibits endosome trafficking to interact with p47phox, thereby suppressing TLR4 inflammatory signaling in macrophages. Derived from the structure of this Rv3364c peptide motif, 2,4-diamino-6-(4-tert-butylphenyl)-1,3,5-trazine, DATPT as a ₁₂WLVSKF₁₇ peptide-mimetic small molecule has been identified. DATPT can block the SNX9-p47phox interaction in the endosome and suppress reactive oxygen species and inflammatory cytokine production; it demonstrated significant therapeutic effects in a mouse model of cecal ligation and puncture-induced sepsis. DATPT has considerably improved potency, with an IC₅₀ 500-fold (in vitro) or 2000-fold (in vivo) lower than that of the ₁₂WLVSKF₁₇ peptide. Furthermore, DATPT shows potent antibacterial activities by reduction in ATP production and leakage of intracellular ATP out of bacteria. These results provide evidence for peptide-derived small molecule DATPT with anti-inflammatory and antibacterial functions for the treatment of sepsis.