Dataset Information

Novel Chimeric Protein Vaccines Against Clostridium difficile Infection.

ABSTRACT: Clostridium difficile infection (CDI) is the leading cause of world-wide nosocomial acquired diarrhea in adults. Active vaccination is generally accepted as a logical and cost-effective approach to prevent CDI. In this paper, we have generated two novel chimeric proteins; one designated Tcd169, comprised of the glucosyltransferase domain (GT), the cysteine proteinase domain (CPD), and receptor binding domain (RBD) of TcdB, and the RBD of TcdA; the other designated Tcd169FI, which contains Salmonella typhimurium flagellin (sFliC) and Tcd169. Both proteins were expressed in and purified from Bacillus megaterium. Point mutations were made in the GT (W102A, D288N) and CPD (C698) of TcdB to ensure that Tcd169 and Tcd169FI were atoxic. Immunization with Tcd169 or Tcd169Fl induced protective immunity against TcdA/TcdB challenge through intraperitoneal injection, also provided mice full protection against infection with a hyper-virulent C. difficile strain (BI/NAP1/027). In addition, inclusion of sFlic in the fusion protein (Tcd169Fl) enhanced its protective immunity against toxin challenge, reduced C. difficile numbers in feces from Tcd169Fl-immunized mice infected C. difficile. Our data show that Tcd169 and Tcd169FI fusion proteins may represent alternative vaccine candidates against CDI.

SUBMITTER: Wang S

PROVIDER: S-EPMC6204379 | biostudies-other | 2018

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Novel Chimeric Protein Vaccines Against <i>Clostridium difficile</i> Infection.

Wang Shaohui S Wang Yuanguo Y Cai Ying Y Kelly Ciaran P CP Sun Xingmin X

Frontiers in immunology 20181022

<i>Clostridium difficile</i> infection (CDI) is the leading cause of world-wide nosocomial acquired diarrhea in adults. Active vaccination is generally accepted as a logical and cost-effective approach to prevent CDI. In this paper, we have generated two novel chimeric proteins; one designated Tcd169, comprised of the glucosyltransferase domain (GT), the cysteine proteinase domain (CPD), and receptor binding domain (RBD) of TcdB, and the RBD of TcdA; the other designated Tcd169FI, which contains ...[more]

PMID: 30405630

Similar Datasets

Project description:Clostridium difficile (C. difficile) is a Gram-positive, spore-forming, toxin-producing anaerobe that can cause nosocomial antibiotic-associated intestinal disease. Autolysin is a lytic enzyme that hydrolyzes peptidoglycans of the bacterial cell wall, with a catalytic domain and cell wall-binding domains, proven to be involved in bacterial cell wall remodeling and cell division. Although autolysins in C. difficile have been reported, the autolysins have failed to yield impressive results when used as exogenous lytic agents. In this study, we expressed and characterized the binding domains (Cwp19-BD and Acd-BD) and catalytic domains (Cwp19-CD, Acd-CD, and Cwl-CD) of C. difficile autolysins, and the domains with the best binding specificity and lytic activity were selected towards C. difficile to design a novel lytic protein Cwl-CWB2. Cwl-CWB2 showed good biosafety with significantly low hemolysis and without cytotoxicity. The results of fluorescence analysis and lytic assay demonstrated that Cwl-CWB2 has higher binding specificity and stronger lytic activity with a minimum inhibitory concentration at 13.39 ± 5.80 μg/mL against living C. difficile cells, which is significantly stronger than commercial lysozyme (3333.33 ± 1443.37 μg/mL) and other reported C. difficile autolysins. Besides, Cwl-CWB2 exhibited good stability as about 75% of the lytic activity was still retained when incubated at 37 °C for 96 h, which is considered to be a potential antimicrobial agent to combat C. difficile. KEY POINTS: • Several binding domains and catalytic domains, deriving from several Clostridium difficile autolysins, were expressed, purified, and functionally characterized. • A novel C. difficile lytic protein Cwl-CWB2 was designed from C. difficile autolysins. • The binding specificity and lytic activity of Cwl-CWB2 against C. difficile showed advantages compared with other reported C. difficile autolysins. • Cwl-CWB2 exhibited significantly low hemolysis and cytotoxicity against normal-derived colon mucosa 460 cell.

Project description:Lantibiotics offer an untapped pipeline for the development of novel antibiotics to treat serious Gram-positive (+) infections including Clostridium difficile. Mutacin 1140 (MU1140) is a lantibiotic produced by Streptococcus mutans and acts via a novel mechanism of action, which may limit the development of resistance. This study sought to identify a lead compound for the treatment of C. difficile associated diarrhea (CDAD). Compounds were selected from a saturation mutagenesis library of 418 single amino acid variants of MU1140. Compounds were produced by small scale fermentation, purified, characterized and then subjected to a panel of assays aimed at identifying the best performers. The screening assays included: in vitro susceptibility testing [MIC against Micrococcus luteus, Clostridium difficile, vancomycin-resistant enterococci (VRE), Staphylococcus aureus, Streptococcus pneumonia, Mycobacterium phlei, and Pseudomonas aeruginosa; cytotoxicity screening on HepG2 hepatocytes; in vitro pharmacological profiling with the Safety Screen 44TM, metabolic and chemical stability in biologically relevant fluids (FaSSGF, FaSSIF and serum); and efficacy in vivo]. Several lantibiotic compounds had better MIC against C. difficile, compared to vancomycin, but not against other bacterial species tested. The Safety Screen 44TMin vitro pharmacological profiling assay suggested that this class of compounds has relatively low overall toxicity and that compound OG253 (MU1140, Phe1Ile) is not likely to present inadvertent off-target effects, as evidenced by a low promiscuity score. The in vitro cytotoxicity assay also indicated that this class of compounds was characterized by low toxicity; the EC50 of OG253 was 636 mg/mL on HepG2 cells. The half-life in simulated gastric fluid was >240 min. for all compound tested. The stability in simulated intestinal fluid ranged between a half-life of 5 min to >240 min, and paralleled the half-life in serum. OG253 ultimately emerged as the lead compound based on superior in vivo efficacy along with an apparent lack of relapse in a hamster model of infection. The lessons learned from this report are applicable to therapeutic lanthipeptides in general and may assist in the design of novel molecules with improved pharmacological, therapeutic and physicochemical profiles. The data presented also support the continued clinical development of OG253 as a novel antibiotic against CDAD that could prevent recurrence of the infection.

Project description:The current picture of Clostridium difficile infection (CDI) is alarming with a mortality rate ranging between 3% and 15% and a CDI recurrence rate ranging from 12% to 40%. Despite the great efforts made over the past 10?years to face the CDI burden, there are still gray areas in our knowledge on CDI management. The traditional anti-CDI antimicrobials are not always adequate in addressing the current needs in CDI management. The aim of our review is to give an update on novel antimicrobials for the treatment of CDI, considering the currently available evidences on their efficacy, safety, molecular mechanism of action, and their probability to be successfully introduced into the clinical practice in the near future. We identified, through a PubMed search, 16 novel antimicrobial molecules under study for CDI treatment: cadazolid, surotomycin, ridinilazole, LFF571, ramoplanin, CRS3123, fusidic acid, nitazoxanide, rifampin, rifaximin, tigecycline, auranofin, NVB302, thuricin CD, lacticin 3147, and acyldepsipeptide antimicrobials. In comparison with the traditional anti-CDI antimicrobial treatment, some of the novel antimicrobials reviewed in this study offer several advantages, i.e., the favorable pharmacokinetic and pharmacodynamic profile, the narrow-spectrum activity against CD that implicates a low impact on the gut microbiota composition, the inhibitory activity on CD sporulation and toxins production. Among these novel antimicrobials, the most active compounds in reducing spore production are cadazolid, ridinilazole, CRS3123, ramoplanin and, potentially, the acyldepsipeptide antimicrobials. These antimicrobials may potentially reduce CD environment spread and persistence, thus reducing CDI healthcare-associated acquisition. However, some of them, i.e., surotomycin, fusidic acid, etc., will not be available due to lack of superiority versus standard of treatment. The most CD narrow-spectrum novel antimicrobials that allow to preserve microbiota integrity are cadazolid, ridinilazole, auranofin, and thuricin CD. In conclusion, the novel antimicrobial molecules under development for CDI have promising key features and advancements in comparison to the traditional anti-CDI antimicrobials. In the near future, some of these new molecules might be effective alternatives to fight CDI.

Dataset Information

Novel Chimeric Protein Vaccines Against Clostridium difficile Infection.

Publications

Novel Chimeric Protein Vaccines Against <i>Clostridium difficile</i> Infection.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets