1
|
Mendes SG, Combo SI, Allain T, Domingues S, Buret AG, Da Silva GJ. Co-regulation of biofilm formation and antimicrobial resistance in Acinetobacter baumannii: from mechanisms to therapeutic strategies. Eur J Clin Microbiol Infect Dis 2023; 42:1405-1423. [PMID: 37897520 PMCID: PMC10651561 DOI: 10.1007/s10096-023-04677-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 10/02/2023] [Indexed: 10/30/2023]
Abstract
In recent years, multidrug-resistant Acinetobacter baumannii has emerged globally as a major threat to the healthcare system. It is now listed by the World Health Organization as a priority one for the need of new therapeutic agents. A. baumannii has the capacity to develop robust biofilms on biotic and abiotic surfaces. Biofilm development allows these bacteria to resist various environmental stressors, including antibiotics and lack of nutrients or water, which in turn allows the persistence of A. baumannii in the hospital environment and further outbreaks. Investigation into therapeutic alternatives that will act on both biofilm formation and antimicrobial resistance (AMR) is sorely needed. The aim of the present review is to critically discuss the various mechanisms by which AMR and biofilm formation may be co-regulated in A. baumannii in an attempt to shed light on paths towards novel therapeutic opportunities. After discussing the clinical importance of A. baumannii, this critical review highlights biofilm-formation genes that may be associated with the co-regulation of AMR. Particularly worthy of consideration are genes regulating the quorum sensing system AbaI/AbaR, AbOmpA (OmpA protein), Bap (biofilm-associated protein), the two-component regulatory system BfmRS, the PER-1 β-lactamase, EpsA, and PTK. Finally, this review discusses ongoing experimental therapeutic strategies to fight A. baumannii infections, namely vaccine development, quorum sensing interference, nanoparticles, metal ions, natural products, antimicrobial peptides, and phage therapy. A better understanding of the mechanisms that co-regulate biofilm formation and AMR will help identify new therapeutic targets, as combined approaches may confer synergistic benefits for effective and safer treatments.
Collapse
Affiliation(s)
- Sérgio G Mendes
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Sofia I Combo
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Thibault Allain
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
| | - Sara Domingues
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal
| | - Andre G Buret
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada
| | - Gabriela J Da Silva
- Departments of Biological Sciences, Inflammation Research Network, University of Calgary, 2500 University Dr. N.W, Calgary, T2N 1N4, Canada.
- Faculty of Pharmacy, University of Coimbra, 3000-548, Coimbra, Portugal.
- Centre for Neuroscience and Cell Biology, University of Coimbra, 3000-548, Coimbra, Portugal.
| |
Collapse
|
2
|
Fatehi Z, Doosti A, Jami MS. Oral vaccination with novel Lactococcus lactis mucosal live vector-secreting Brucella lumazine synthase (BLS) protein induces humoral and cellular immune protection against Brucella abortus. Arch Microbiol 2023; 205:122. [PMID: 36939918 PMCID: PMC10025791 DOI: 10.1007/s00203-023-03471-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2023] [Revised: 02/25/2023] [Accepted: 03/07/2023] [Indexed: 03/21/2023]
Abstract
This work aimed to provide recombinant Lactococcus lactis as a potential live vector for the manufacture of recombinant Brucella abortus (rBLS-Usp45). The sequences of the genes were collected from the GenBank database. Using Vaxijen and ccSOL, the proteins' immunogenicity and solubility were evaluated. Mice were given oral vaccinations with recombinant L. lactis. Anti-BLS-specific IgG antibodies were measured by ELISA assay. Cytokine reactions were examined using real-time PCR and the ELISA technique. The BLS protein was chosen for immunogenicity based on the vaccinology screening findings since it had maximum solubility and antigenic values of 99% and 0.75, respectively. The BLS gene, digested at 477 bp, was electrophoretically isolated to demonstrate that the recombinant plasmid was successfully produced. Protein-level antigen expression showed that the target group produced the 18 kDa-sized BLS protein, whereas the control group did not express any proteins. In the sera of mice given the L. lactis-pNZ8148-BLS-Usp45 vaccine 14 days after priming, there was a significant level of BLS-specific IgG1, IgG2a (P < 0.001) compared to the PBS control group. Vaccinated mice showed higher levels of IFN-γ, TNFα, IL-4, and IL-10 in samples obtained on days 14 and 28, after receiving the L. lactis-pNZ8148-BLS-Usp45 and IRBA vaccines (P < 0.001). The inflammatory reaction caused less severe spleen injuries, alveolar edema, lymphocyte infiltration, and morphological damage in the target group's spleen sections. Based on our findings, an oral or subunit-based vaccine against brucellosis might be developed using L. lactis-pNZ8148-BLS-Usp45 as a novel, promising, and safe alternative to the live attenuated vaccines now available.
Collapse
Affiliation(s)
- Zahra Fatehi
- Department of Biology, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Abbas Doosti
- Biotechnology Research Center, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran.
| | - Mohammad Saeid Jami
- Department of Biology, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
- Cellular and Molecular Research Center, Basic Health Sciences Research Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| |
Collapse
|
3
|
Hu Y, Zhang X, Deng S, Yue C, Jia X, Lyu Y. Non-antibiotic prevention and treatment against Acinetobacter baumannii infection: Are vaccines and adjuvants effective strategies? Front Microbiol 2023; 14:1049917. [PMID: 36760499 PMCID: PMC9905804 DOI: 10.3389/fmicb.2023.1049917] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 01/09/2023] [Indexed: 01/26/2023] Open
Abstract
Acinetobacter baumannii (A. baumannii) is a Gram-negative opportunistic pathogen widely attached to the surface of medical instruments, making it one of the most common pathogens of nosocomial infection, and often leading to cross-infection and co-infection. Due to the extensive antibiotic and pan-resistance, A. baumannii infection is facing fewer treatment options in the clinic. Therefore, the prevention and treatment of A. baumannii infection have become a tricky global problem. The requirement for research and development of the new strategy is urgent. Now, non-antibiotic treatment strategies are urgently needed. This review describes the research on A. baumannii vaccines and antibacterial adjuvants, discusses the advantages and disadvantages of different candidate vaccines tested in vitro and in vivo, especially subunit protein vaccines, and shows the antibacterial efficacy of adjuvant drugs in monotherapy.
Collapse
Affiliation(s)
- Yue Hu
- Yan'an Key Laboratory of Microbial Drug Innovation and Transformation, School of Basic Medicine, Yan'an University, Yan'An, China,Non-coding RNA and Drug Discovery Key Laboratory of Sichuan Province, Chengdu Medical College, Chengdu, China
| | - Xianqin Zhang
- School of Basic Medical Sciences, Chengdu Medical College, Chengdu, China
| | - Shanshan Deng
- Non-coding RNA and Drug Discovery Key Laboratory of Sichuan Province, Chengdu Medical College, Chengdu, China,School of Basic Medical Sciences, Chengdu Medical College, Chengdu, China
| | - Changwu Yue
- Yan'an Key Laboratory of Microbial Drug Innovation and Transformation, School of Basic Medicine, Yan'an University, Yan'An, China,*Correspondence: Changwu Yue ✉
| | - Xu Jia
- Non-coding RNA and Drug Discovery Key Laboratory of Sichuan Province, Chengdu Medical College, Chengdu, China,School of Basic Medical Sciences, Chengdu Medical College, Chengdu, China,Xu Jia ✉
| | - Yuhong Lyu
- Yan'an Key Laboratory of Microbial Drug Innovation and Transformation, School of Basic Medicine, Yan'an University, Yan'An, China,Yuhong Lyu ✉
| |
Collapse
|
4
|
Haghighi N, Doosti A, Kiani J. Evaluation of Apoptosis, Cell Proliferation and Cell Cycle Progression by Inactivation of the NEAT1 Long Noncoding RNA in a Renal Carcinoma Cell Line Using CRISPR/Cas9. IRANIAN JOURNAL OF BIOTECHNOLOGY 2023; 21:e3180. [PMID: 36811109 PMCID: PMC9938936 DOI: 10.30498/ijb.2022.310632.3180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/16/2021] [Accepted: 03/06/2022] [Indexed: 02/24/2023]
Abstract
Background Long noncoding RNAs (lncRNAs) play an important role in cellular mechanisms including transcription, translation, and apoptosis. NEAT1 is one of the essential types of lncRNAs in humans that can bind to active genes and modify their transcription. NEAT1 upregulation in various forms of cancer such as kidney cancer has been reported. Kidney cancer accounts for approximately 3% of all cancers worldwide and occurs almost twice as often in men as in women. Objectives This study has been performed to knockout the NEAT1 gene using the CRISPR/Cas9 technique in the Renal Cell Carcinoma ACHN cell line and to evaluate its effects on cancer progression and apoptosis. Material and Methods Two specific (single guide RNA (sgRNA) sequences for the NEAT1 gene were designed by CHOPCHOP software. These sequences were then cloned into plasmid pSpcas9, and recombinant vectors PX459-sgRNA1 and PX459-sgRNA2 were generated. ACHN cells were transfected using recombinant vectors carrying sgRNA1 and sgRNA2. The expression level of apoptosis-related genes was assessed by real-time PCR. Annexin, MTT and cell scratch tests were performed to evaluate the survival, proliferation, and migration of the knocked out cells, respectively. Results The results have shown successful knockout of the NEAT1 gene in the cells of the treatment group. Expressions of P53, BAK, BAX and FAS genes in the cells of the treatment group (NEAT1 knockout) showed significant increases in expression compared to the cells of the control group (P <0.01). Additionally, decreased expression of BCL2 and survivin genes was observed in knockout cells compared to the control group (p <0.05). In addition, in the cells of the treatment group compared to control cells, a significant decrease in cell viability, ability to migrate and cell growth and proliferation was observed. Conclusion Inactivation of the NEAT1 gene in ACHN cell line using CRISPR/Cas9 technology elevated apoptosis and reduced cell survival and proliferation which makes it a novel target for kidney cancer therapeutics.
Collapse
Affiliation(s)
- Nastaran Haghighi
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Abbas Doosti
- Biotechnology Research Center, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Jafar Kiani
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran,
Department of Molecular Medicine, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences (IUMS), Tehran, Iran
| |
Collapse
|
5
|
Jeffreys S, Chambers JP, Yu JJ, Hung CY, Forsthuber T, Arulanandam BP. Insights into Acinetobacter baumannii protective immunity. Front Immunol 2022; 13:1070424. [PMID: 36466845 PMCID: PMC9716351 DOI: 10.3389/fimmu.2022.1070424] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 11/07/2022] [Indexed: 11/19/2022] Open
Abstract
Acinetobacter baumannii is a nosocomic opportunistic Gram-negative bacteria known for its extensive drug-resistant phenotype. A. baumannii hospital-acquired infections are major contributors to increased costs and mortality observed during the COVID-19 pandemic. With few effective antimicrobials available for treatment of this pathogen, immune-based therapy becomes an attractive strategy to combat multi-drug resistant Acinetobacter infection. Immunotherapeutics is a field of growing interest with advances in vaccines and monoclonal antibodies providing insight into the protective immune response required to successfully combat this pathogen. This review focuses on current knowledge describing the adaptive immune response to A. baumannii, the importance of antibody-mediated protection, developments in cell-mediated protection, and their respective therapeutic application going forward. With A. baumannii’s increasing resistance to most current antimicrobials, elucidating an effective host adaptive immune response is paramount in the guidance of future immunotherapeutic development.
Collapse
Affiliation(s)
- Sean Jeffreys
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
| | - James P. Chambers
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
| | - Jieh-Juen Yu
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
| | - Chiung-Yu Hung
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
| | - Thomas Forsthuber
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
| | - Bernard P. Arulanandam
- Department of Molecular Microbiology and Immunology, University of Texas at San Antonio, San Antonio, TX, United States
- Department of Immunology, Tufts University School of Medicine, Boston, MA, United States
- *Correspondence: Bernard P. Arulanandam,
| |
Collapse
|
6
|
Piri-Gharaghie T, Doosti A, Mirzaei SA. Fabrication and Characterization of pcDNA3.1(+) Location within Chitosan/Nanoparticles Complexes for Enhanced Gene Delivery. IRANIAN JOURNAL OF BIOTECHNOLOGY 2022; 20:e3110. [PMID: 36381280 PMCID: PMC9618014 DOI: 10.30498/ijb.2022.297534.3110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
BACKGROUND Chitosan nanoparticles (CSNP) are becoming a popular alternative for delivering nucleic acids to tissues for gene transfer (gene therapy). The size and morphology of these biodegradable nano-carriers are adjustable, and their positive charge allows them to interact strongly with negatively charged nucleic acids. OBJECTIVE This study aimed to fabricate and characterize pcDNA3.1 (+) plasmid (pDNA) and CSNP complexes and determine the plasmid location in these vehicles. MATERIALS AND METHODS The characteristics of the pDNA/CSNP complex after production were investigated by SEM, XRD, DLS, TGA, and FTIR. The capacity of CSNP to form complexes with pDNA was investigated by labeling free plasmids with the fluorescent intercalating dye OliGreen. The stability of pDNA/CSNP in the presence of chitosanase was evaluated. Surface-Enhanced Raman Spectroscopy (SERS) for pDNA localization was performed, and absorption rate in BALB/c mice was assessed by real-time PCR. RESULTS The optimum pDNA/CSNP ratio for plasmid complex formation was established to be 1:2 (w.w) by measuring spectroscopy. At these optimum complex formation ratios, spectroscopy, and gel digest experiments, SERS indicated that a part of the pDNA was present on the complex outer surface. The findings of plasmid absorption in mouse thigh tissue by real-time PCR revealed that the rate of gene uptake was significantly greater at a dose of 1:2 (w.w) of pDNA/CSNP than in other groups (P< 0.001). CONCLUSIONS The findings of this study reveal exactly pDNA fits into polymer nanostructured delivery systems, allowing the formulation to be adjusted for selective distribution. This understanding will aid future research into the system's functioning in vitro and in vivo.
Collapse
Affiliation(s)
- Tohid Piri-Gharaghie
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Abbas Doosti
- Biotechnology Research Center, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
| | - Seyed Abbas Mirzaei
- Department of Biology, Faculty of Basic Sciences, Shahrekord Branch, Islamic Azad University, Shahrekord, Iran
- Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord, Iran
| |
Collapse
|
7
|
Tan YC, Lahiri C. Promising Acinetobacter baumannii Vaccine Candidates and Drug Targets in Recent Years. Front Immunol 2022; 13:900509. [PMID: 35720310 PMCID: PMC9204607 DOI: 10.3389/fimmu.2022.900509] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 04/26/2022] [Indexed: 12/14/2022] Open
Abstract
In parallel to the uncontrolled use of antibiotics, the emergence of multidrug-resistant bacteria, like Acinetobacter baumannii, has posed a severe threat. A. baumannii predominates in the nosocomial setting due to its ability to persist in hospitals and survive antibiotic treatment, thereby eventually leading to an increasing prevalence and mortality due to its infection. With the increasing spectra of drug resistance and the incessant collapse of newly discovered antibiotics, new therapeutic countermeasures have been in high demand. Hence, recent research has shown favouritism towards the long-term solution of designing vaccines. Therefore, being a realistic alternative strategy to combat this pathogen, anti-A. Baumannii vaccines research has continued unearthing various antigens with variable results over the last decade. Again, other approaches, including pan-genomics, subtractive proteomics, and reverse vaccination strategies, have shown promise for identifying promiscuous core vaccine candidates that resulted in chimeric vaccine constructs. In addition, the integration of basic knowledge of the pathobiology of this drug-resistant bacteria has also facilitated the development of effective multiantigen vaccines. As opposed to the conventional trial-and-error approach, incorporating the in silico methods in recent studies, particularly network analysis, has manifested a great promise in unearthing novel vaccine candidates from the A. baumannii proteome. Some studies have used multiple A. baumannii data sources to build the co-functional networks and analyze them by k-shell decomposition. Additionally, Whole Genomic Protein Interactome (GPIN) analysis has utilized a rational approach for identifying essential proteins and presenting them as vaccines effective enough to combat the deadly pathogenic threats posed by A. baumannii. Others have identified multiple immune nodes using network-based centrality measurements for synergistic antigen combinations for different vaccination strategies. Protein-protein interactions have also been inferenced utilizing structural approaches, such as molecular docking and molecular dynamics simulation. Similar workflows and technologies were employed to unveil novel A. baumannii drug targets, with a similar trend in the increasing influx of in silico techniques. This review integrates the latest knowledge on the development of A. baumannii vaccines while highlighting the in silico methods as the future of such exploratory research. In parallel, we also briefly summarize recent advancements in A. baumannii drug target research.
Collapse
Affiliation(s)
- Yong Chiang Tan
- School of Postgraduate Studies, International Medical University, Kuala Lumpur, Malaysia
| | - Chandrajit Lahiri
- Department of Biological Sciences, Sunway University, Petaling Jaya, Malaysia
| |
Collapse
|
8
|
Hagag YA, Said HS, Kenawy HI, Hassan R. A novel pentavalent vaccine candidate completely protects against Acinetobacter baumannii in a mouse model of peritonitis. Appl Microbiol Biotechnol 2022; 106:8151-8167. [PMID: 36401642 PMCID: PMC9676856 DOI: 10.1007/s00253-022-12231-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/30/2022] [Accepted: 10/05/2022] [Indexed: 11/21/2022]
Abstract
Acinetobacter baumannii is considered as one of the most virulent and infectious organisms that have an increased ability to both evade host immune response and resist various classes of antibiotics, leading to life-threatening infections. Multiple virulence factors have been implicated in the high prevalence rate of A. baumannii in hospitalized and immunocompromised patients. Moreover, improper use of antibiotics has led to the emergence of extensive drug-resistant strains that urgently require alternative strategies to control this superbug. Unfortunately, the availability of a licensed vaccine against A. baumannii infections is still challenged by the vast diversity among A. baumannii strains. Here, we report the development of a novel pentavalent vaccine candidate composed of two recombinant proteins (Wza and YiaD) and a pool of capsular polysaccharides isolated from 3 clinical isolates. We tested this new vaccine in vivo in a mouse model of peritonitis against the standard strain ATCC 19606 in addition to 3 clinical isolates of A. baumannii. Immunization with this vaccine completely protected the challenged mice with 100% survival rate in the case of all the tested bacteria. Further clinical studies are urgently needed to evaluate the efficacy and safety of this proprietary vaccine to protect patients from A. baumannii lethal infections. KEY POINTS: • Recombinant proteins pool (Wza and YiaD) immunization led to a synergistic immune response. • Capsular polysaccharides pool induced up to 90% protection of tested clinical isolates. • The pentavalent pool showed superiority with 100% survival of immunized mice.
Collapse
Affiliation(s)
- Yomna A. Hagag
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Heba Shehta Said
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Hany I. Kenawy
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| | - Ramadan Hassan
- Department of Microbiology and Immunology, Faculty of Pharmacy, Mansoura University, Mansoura, 35516 Egypt
| |
Collapse
|
9
|
Khalid K, Irum S, Ullah SR, Andleeb S. In-Silico Vaccine Design Based on a Novel Vaccine Candidate Against Infections Caused by Acinetobacter baumannii. Int J Pept Res Ther 2021; 28:16. [PMID: 34873398 PMCID: PMC8636788 DOI: 10.1007/s10989-021-10316-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/26/2021] [Indexed: 12/24/2022]
Abstract
Acinetobacter baumannii is notorious for causing serious infections of the skin, lungs, soft tissues, bloodstream, and urinary tract. Despite the overwhelming information available so far, there has still been no approved vaccine in the market to prevent these infections. Therefore, this study focuses on developing a rational vaccine design using the technique of epitope mapping to curb the infections caused by A. baumannii. An outer membrane protein with immunogenic potential as well as all the properties of a good vaccine candidate was selected and used to calculate epitopes for selection on the basis of a low percentile rank, high binding scores, good immunological properties, and non-allergenicity. Thus, a 240 amino-acid vaccine sequence was obtained by manually joining all the epitopes in sequence-wise manner with the appropriate linkers, namely AAY, GPGPG, and EAAAK. Additionally, a 50S ribosomal protein L7/L12, agonist to the human innate immune receptors was attached to the N-terminus to increase the overall immune response towards the vaccine. As a result, enhanced overall protein stability, expression, immunostimulatory capabilities, and solubility of the designed construct were observed. Molecular dynamic simulations revealed the compactness and stability of the polypeptide construct. Moreover, molecular docking exhibited strong binding of the designed vaccine with TLR-4 and TLR-9. In-silico immune simulations indicated an immense increment in T-cell and B-cell populations. Bioinformatic tools also significantly assisted with optimizing codons which allowed for successful cloning of constructs into desired host vectors. Using in-silico tools to design a vaccine against A. baumannii demonstrated that this construct could pave the way for successfully combating infections caused by multidrug-resistant bacteria.
Collapse
Affiliation(s)
- Kashaf Khalid
- Department of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, 44000 Pakistan
| | - Sidra Irum
- Department of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, 44000 Pakistan
| | - Sidra Rahmat Ullah
- Department of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, 44000 Pakistan
| | - Saadia Andleeb
- Department of Industrial Biotechnology, Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, 44000 Pakistan
| |
Collapse
|
10
|
Ma C, McClean S. Mapping Global Prevalence of Acinetobacter baumannii and Recent Vaccine Development to Tackle It. Vaccines (Basel) 2021; 9:vaccines9060570. [PMID: 34205838 PMCID: PMC8226933 DOI: 10.3390/vaccines9060570] [Citation(s) in RCA: 35] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/16/2021] [Accepted: 05/22/2021] [Indexed: 12/23/2022] Open
Abstract
Acinetobacter baumannii is a leading cause of nosocomial infections that severely threaten public health. The formidable adaptability and resistance of this opportunistic pathogen have hampered the development of antimicrobial therapies which consequently leads to very limited treatment options. We mapped the global prevalence of multidrug-resistant A. baumannii and showed that carbapenem-resistant A. baumannii is widespread throughout Asia and the Americas. Moreover, when antimicrobial resistance rates of Acinetobacter spp. exceed a threshold level, the proportion of A. baumannii isolates from clinical samples surges. Therefore, vaccines represent a realistic alternative strategy to tackle this pathogen. Research into anti-A. baumannii vaccines have enhanced in the past decade and multiple antigens have been investigated preclinically with varying results. This review summarises the current knowledge of virulence factors relating to A. baumannii–host interactions and its implication in vaccine design, with a view to understanding the current state of A. baumannii vaccine development and the direction of future efforts.
Collapse
|
11
|
Martinez J, Razo-Gutierrez C, Le C, Courville R, Pimentel C, Liu C, Fung SE, Tuttobene MR, Phan K, Vila AJ, Shahrestani P, Jimenez V, Tolmasky ME, Becka SA, Papp-Wallace KM, Bonomo RA, Soler-Bistue A, Sieira R, Ramirez MS. Cerebrospinal fluid (CSF) augments metabolism and virulence expression factors in Acinetobacter baumannii. Sci Rep 2021; 11:4737. [PMID: 33637791 PMCID: PMC7910304 DOI: 10.1038/s41598-021-81714-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 01/06/2021] [Indexed: 12/14/2022] Open
Abstract
In a recent report by the Centers for Disease Control and Prevention (CDC), multidrug resistant (MDR) Acinetobacter baumannii is a pathogen described as an "urgent threat." Infection with this bacterium manifests as different diseases such as community and nosocomial pneumonia, bloodstream infections, endocarditis, infections of the urinary tract, wound infections, burn infections, skin and soft tissue infections, and meningitis. In particular, nosocomial meningitis, an unwelcome complication of neurosurgery caused by extensively-drug resistant (XDR) A. baumannii, is extremely challenging to manage. Therefore, understanding how A. baumannii adapts to different host environments, such as cerebrospinal fluid (CSF) that may trigger changes in expression of virulence factors that are associated with the successful establishment and progress of this infection is necessary. The present in-vitro work describes, the genetic changes that occur during A. baumannii infiltration into CSF and displays A. baumannii's expansive versatility to persist in a nutrient limited environment while enhancing several virulence factors to survive and persist. While a hypervirulent A. baumannii strain did not show changes in its transcriptome when incubated in the presence of CSF, a low-virulence isolate showed significant differences in gene expression and phenotypic traits. Exposure to 4% CSF caused increased expression of virulence factors such as fimbriae, pilins, and iron chelators, and other virulence determinants that was confirmed in various model systems. Furthermore, although CSF's presence did not enhance bacterial growth, an increase of expression of genes encoding transcription, translation, and the ATP synthesis machinery was observed. This work also explores A. baumannii's response to an essential component, human serum albumin (HSA), within CSF to trigger the differential expression of genes associated with its pathoadaptibility in this environment.
Collapse
Affiliation(s)
- Jasmine Martinez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Chelsea Razo-Gutierrez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Casin Le
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Robert Courville
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Camila Pimentel
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Christine Liu
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Sammie E Fung
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Marisel R Tuttobene
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Kimberly Phan
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Alejandro J Vila
- Instituto de Biología Molecular Y Celular de Rosario (IBR, CONICET-UNR), Rosario, Argentina
- Área Biofísica, Facultad de Ciencias Bioquímicas Y Farmacéuticas, Universidad Nacional de Rosario, Rosario, Argentina
| | - Parvin Shahrestani
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Veronica Jimenez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Marcelo E Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA
| | - Scott A Becka
- Research Service and GRECC, Department of Veterans Affairs Medical Center, Louis Stokes Cleveland, Cleveland, OH, USA
| | - Krisztina M Papp-Wallace
- Research Service and GRECC, Department of Veterans Affairs Medical Center, Louis Stokes Cleveland, Cleveland, OH, USA
- Departments of Medicine, Pharmacology, Molecular Biology and Microbiology, Biochemistry, Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- CWRU-Cleveland VAMC Center for Antimicrobial Resistance and Epidemiology (Case VA CARES), Cleveland, OH, USA
| | - Robert A Bonomo
- Research Service and GRECC, Department of Veterans Affairs Medical Center, Louis Stokes Cleveland, Cleveland, OH, USA
- Departments of Medicine, Pharmacology, Molecular Biology and Microbiology, Biochemistry, Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, Cleveland, OH, USA
- CWRU-Cleveland VAMC Center for Antimicrobial Resistance and Epidemiology (Case VA CARES), Cleveland, OH, USA
| | - Alfonso Soler-Bistue
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San Martín-Consejo Nacional de Investigaciones Científicas Y Técnicas, San Martín, Buenos Aires, Argentina
| | - Rodrigo Sieira
- Fundación Instituto Leloir - IIBBA CONICET, Buenos Aires, Argentina
| | - Maria Soledad Ramirez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, 800 N State College Blvd, Fullerton, CA, 92831, USA.
| |
Collapse
|
12
|
Recent Advances in the Pursuit of an Effective Acinetobacter baumannii Vaccine. Pathogens 2020; 9:pathogens9121066. [PMID: 33352688 PMCID: PMC7766458 DOI: 10.3390/pathogens9121066] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 12/15/2020] [Accepted: 12/17/2020] [Indexed: 12/22/2022] Open
Abstract
Acinetobacter baumannii has been a major cause of nosocomial infections for decades. The absence of an available vaccine coupled with emerging multidrug resistance has prevented the medical community from effectively controlling this human pathogen. Furthermore, the ongoing pandemic caused by SARS-CoV-2 has increased the risk of hospitalized patients developing ventilator-associated pneumonia caused by bacterial opportunists including A. baumannii. The shortage of antibiotics in the development pipeline prompted the World Health Organization to designate A. baumannii a top priority for the development of new medical countermeasures, such as a vaccine. There are a number of important considerations associated with the development of an A. baumannii vaccine, including strain characteristics, diverse disease manifestations, and target population. In the past decade, research efforts have revealed a number of promising new immunization strategies that could culminate in a safe and protective vaccine against A. baumannii. In this review, we highlight the recent progress in the development of A. baumannii vaccines, discuss potential challenges, and propose future directions to achieve an effective intervention against this human pathogen.
Collapse
|
13
|
Holley CL, Ayala JC, Shafer WM. Transcriptional control of the gonococcal ompA gene by the MisR/MisS two-component regulatory system. Sci Rep 2020; 10:9425. [PMID: 32523077 PMCID: PMC7286886 DOI: 10.1038/s41598-020-66382-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 05/20/2020] [Indexed: 11/11/2022] Open
Abstract
Neisseria gonorrhoeae, the causative agent of gonorrhea, is an exclusive human pathogen whose growing antibiotic resistance is causing worldwide concern. The increasing rise of antibiotic resistance expressed by gonococci highlights the need to find alternative approaches to current gonorrhea treatment such as vaccine development or novel therapeutics. The gonococcal OmpA protein was previously identified as a potential vaccine candidate due to its conservation and stable expression amongst strains of Neisseria gonorrhoeae. However, factors that might modulate levels of OmpA and therefore potential vaccine efficacy are unknown. Earlier work indicated that ompA is part of the MisR/MisS regulon and suggested that it was a MisR-activated gene. Herein, we confirmed MisR/MisS regulation of ompA and report that the MisR response regulator can bind upstream of the ompA translational start codon. Further, we describe the contribution of a DNA sequence upstream of the ompA promoter that is critical for MisR activation of ompA transcription. Our results provide a framework for understanding the transcription of gonococcal ompA through a regulatory system known to be important for survival of gonococci during experimental infection.
Collapse
Affiliation(s)
- Concerta L Holley
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, 30032, USA
| | - Julio C Ayala
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, 30032, USA
| | - William M Shafer
- Department of Microbiology and Immunology, Emory University School of Medicine, Atlanta, GA, 30032, USA.
- The Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, GA, 30032, USA.
- Laboratories of Bacterial Pathogenesis, Veterans Affairs Medical Center, Decatur, GA, 30039, USA.
| |
Collapse
|
14
|
Outer membrane protein A (OmpA) as a potential therapeutic target for Acinetobacter baumannii infection. J Biomed Sci 2020; 27:26. [PMID: 31954394 PMCID: PMC6969976 DOI: 10.1186/s12929-020-0617-7] [Citation(s) in RCA: 125] [Impact Index Per Article: 31.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Accepted: 01/14/2020] [Indexed: 01/12/2023] Open
Abstract
Acinetobacter baumannii (A. baumannii) is an important opportunistic pathogen causing serious nosocomial infections, which is considered as the most threatening Gram-negative bacteria (GNB). Outer membrane protein A (OmpA), a major component of outer membrane proteins (OMPs) in GNB, is a key virulence factor which mediates bacterial biofilm formation, eukaryotic cell infection, antibiotic resistance and immunomodulation. The characteristics of OmpA in Escherichia coli (E. coli) have been extensively studied since 1974, but only in recent years researchers started to clarify the functions of OmpA in A. baumannii. In this review, we summarized the structure and functions of OmpA in A. baumannii (AbOmpA), collected novel therapeutic strategies against it for treating A. baumannii infection, and emphasized the feasibility of using AbOmpA as a potential therapeutic target.
Collapse
|
15
|
Kaviani R, Pouladi I, Niakan M, Mirnejad R. Molecular Detection of Adefg Efflux Pump Genes and their Contribution to Antibiotic Resistance in Acinetobacter baumannii Clinical Isolates. Rep Biochem Mol Biol 2020; 8:413-418. [PMID: 32582800 PMCID: PMC7275827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2019] [Accepted: 03/19/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Acinetobacter baumannii (A. baumannii) is one of the most important bacteria causing nosocomial infections worldwide. Over the past few years, several strains of A. baumannii have shown antibiotic resistance, which may be due to the activity of efflux pumps. This study was aimed to detect AdeFG efflux pump genes and their contribution to antibiotic resistance in A. baumannii clinical isolates. METHODS A total of 200 A. baumannii clinical isolates were collected from clinical specimens of ulcers, pus, sputum, and blood. All isolates were identified using standard biochemical tests. After identifying and cleaving the genome by boiling, PCR was performed on samples using specific primers. The antimicrobial susceptibility patterns were determined by disk diffusion, with and without CCCP efflux pump inhibitor were determined according to CLSI guidelines. RESULTS We identified 60 clinical isolates of A. baumannii using biochemical differential tests. Identification of all A. baumannii isolates was confirmed by blaOXA-51-like PCR. According to the results of our study, 98.37% of A. baumannii isolates were resistant to ciprofloxacin, norfloxacin, and levofloxacin. PCR results indicated that all 60 A. baumannii isolates contained the AdeF and 76.66% contained AdeG. CONCLUSION the results of this study demonstrated that most of the A. baumannii isolates contained AdeF and AdeG efflux pump genes, and more than 98% of the isolates were resistant to ciprofloxacin, norfloxacin, and levofloxacin. This reflected the significant contribution of efflux pumps to the development of resistance to these antibiotics.
Collapse
Affiliation(s)
- Rasoul Kaviani
- Department of Medical Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran.
| | - Iman Pouladi
- Student Research Committee, Faculty of Medicine, Lorestan University of Medical Sciences, Khorramabad, Iran.
| | - Mohammad Niakan
- Department of Medical Microbiology, Faculty of Medicine, Shahed University, Tehran, Iran.
| | - Reza Mirnejad
- Molecular Biology Research Center, System biology and Poisoning institute, Baqiyatallah University of Medical Sciences, Tehran, Iran.
| |
Collapse
|
16
|
Vaca DJ, Thibau A, Schütz M, Kraiczy P, Happonen L, Malmström J, Kempf VAJ. Interaction with the host: the role of fibronectin and extracellular matrix proteins in the adhesion of Gram-negative bacteria. Med Microbiol Immunol 2019; 209:277-299. [PMID: 31784893 PMCID: PMC7248048 DOI: 10.1007/s00430-019-00644-3] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 11/14/2019] [Indexed: 01/03/2023]
Abstract
The capacity of pathogenic microorganisms to adhere to host cells and avoid clearance by the host immune system is the initial and most decisive step leading to infections. Bacteria have developed different strategies to attach to diverse host surface structures. One important strategy is the adhesion to extracellular matrix (ECM) proteins (e.g., collagen, fibronectin, laminin) that are highly abundant in connective tissue and basement membranes. Gram-negative bacteria express variable outer membrane proteins (adhesins) to attach to the host and to initiate the process of infection. Understanding the underlying molecular mechanisms of bacterial adhesion is a prerequisite for targeting this interaction by “anti-ligands” to prevent colonization or infection of the host. Future development of such “anti-ligands” (specifically interfering with bacteria-host matrix interactions) might result in the development of a new class of anti-infective drugs for the therapy of infections caused by multidrug-resistant Gram-negative bacteria. This review summarizes our current knowledge about the manifold interactions of adhesins expressed by Gram-negative bacteria with ECM proteins and the use of this information for the generation of novel therapeutic antivirulence strategies.
Collapse
Affiliation(s)
- Diana J Vaca
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Arno Thibau
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Monika Schütz
- Institute for Medical Microbiology and Infection Control, University Hospital, Eberhard Karls-University, Tübingen, Germany
| | - Peter Kraiczy
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany
| | - Lotta Happonen
- Division of Infection Medicine, Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Johan Malmström
- Division of Infection Medicine, Department of Clinical Sciences, Faculty of Medicine, Lund University, Lund, Sweden
| | - Volkhard A J Kempf
- Institute for Medical Microbiology and Infection Control, University Hospital, Goethe University Frankfurt am Main, Paul-Ehrlich-Str. 40, 60596, Frankfurt, Germany.
| |
Collapse
|