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Ho KW, Liu YL, Liao TY, Liu ES, Cheng TL. Strategies for Non-Covalent Attachment of Antibodies to PEGylated Nanoparticles for Targeted Drug Delivery. Int J Nanomedicine 2024; 19:10045-10064. [PMID: 39371476 PMCID: PMC11453133 DOI: 10.2147/ijn.s479270] [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: 05/29/2024] [Accepted: 09/05/2024] [Indexed: 10/08/2024] Open
Abstract
Polyethylene glycol (PEG)-modified nanoparticles (NPs) often struggle with reduced effectiveness against metastasis and liquid tumors due to limited tumor cell uptake and therapeutic efficacy. To address this, actively targeted liposomes with enhanced tumor selectivity and internalization are being developed to improve uptake and treatment outcomes. Using bi-functional proteins to functionalize PEGylated NPs and enhance targeted drug delivery through non-covalent attachment methods has emerged as a promising approach. Among these, the one-step and two-step targeting strategies stand out for their simplicity, efficiency, and versatility. The one-step strategy integrates streptavidin-tagged antibodies or bispecific antibodies (bsAbs: PEG/DIG × marker) directly into PEGylated NPs. This method uses the natural interactions between antibodies and PEG for stable, specific binding, allowing the modification of biotin/Fc-binding molecules like protein A, G, or anti-Fc peptide. Simply mixing bsAbs with PEGylated NPs improves tumor targeting and internalization. The two-step strategy involves first accumulating bsAbs (PEG/biotin × tumor marker) on the tumor cell surface, triggering an initial attack via antibody-dependent and complement-dependent cytotoxicity. These bsAbs then capture PEGylated NPs, initiating a second wave of internalization and cytotoxicity. Both strategies aim to enhance the targeting capabilities of PEGylated NPs by enabling specific recognition and binding to disease-specific markers or receptors. This review provides potential pathways for accelerating clinical translation in the development of targeted nanomedicine.
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Affiliation(s)
- Kai-Wen Ho
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Yen-Ling Liu
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tzu-Yi Liao
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - En-Shuo Liu
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
| | - Tian-Lu Cheng
- Department of Biomedical Science and Environmental Biology, Kaohsiung Medical University, Kaohsiung, Taiwan
- Drug Development and Value Creation Research Center, Kaohsiung Medical University, Kaohsiung, Taiwan
- Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung, Taiwan
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Ek M, Nilvebrant J, Nygren PÅ, Ståhl S, Lindberg H, Löfblom J. An anti-sortilin affibody-peptide fusion inhibits sortilin-mediated progranulin degradation. Front Immunol 2024; 15:1437886. [PMID: 39185427 PMCID: PMC11342335 DOI: 10.3389/fimmu.2024.1437886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2024] [Accepted: 07/23/2024] [Indexed: 08/27/2024] Open
Abstract
Heterozygous loss-of-function mutations in the GRN gene are a common cause of frontotemporal dementia. Such mutations lead to decreased plasma and cerebrospinal fluid levels of progranulin (PGRN), a neurotrophic factor with lysosomal functions. Sortilin is a negative regulator of extracellular PGRN levels and has shown promise as a therapeutic target for frontotemporal dementia, enabling increased extracellular PGRN levels through inhibition of sortilin-mediated PGRN degradation. Here we report the development of a high-affinity sortilin-binding affibody-peptide fusion construct capable of increasing extracellular PGRN levels in vitro. By genetic fusion of a sortilin-binding affibody generated through phage display and a peptide derived from the progranulin C-terminus, an affinity protein (A3-PGRNC15*) with 185-pM affinity for sortilin was obtained. Treating PGRN-secreting and sortilin-expressing human glioblastoma U-251 cells with the fusion protein increased extracellular PGRN levels up to 2.5-fold, with an EC50 value of 1.3 nM. Our results introduce A3-PGRNC15* as a promising new agent with therapeutic potential for the treatment of frontotemporal dementia. Furthermore, the work highlights means to increase binding affinity through synergistic contribution from two orthogonal polypeptide units.
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Affiliation(s)
| | | | | | | | | | - John Löfblom
- Department of Protein Science, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, Sweden
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Okabe K, Chikasue K, Murakami K, Matsuda N, Yamada S. Suppressed distribution of protein A on the surface of Staphylococcus aureus as a morphological characteristic of erythromycin-resistant strain. Med Mol Morphol 2024; 57:101-109. [PMID: 38386083 DOI: 10.1007/s00795-023-00379-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/24/2023] [Indexed: 02/23/2024]
Abstract
To identify a new morphological phenotype of erythromycin (EM)-resistant Staphylococcus aureus (S. aureus) were isolated in vitro from EM-sensitive parent strain, and the distribution of staphylococcus specific protein A (SpA) on the surface of these strains was examined morphologically by using applied immunoelectron microscopy. The isolated EM-resistant strains had thickened cell walls, and the distribution of SpA on the surfaces of these strains was demonstrated to be lower than that of the parent strain. The SpA suppression was confirmed by enzyme-linked immunosorbent assay (ELISA) using fixed EM-resistant cells. Moreover, the spa gene of EM-resistant cells was detected by polymerase chain reaction (PCR) and confirmed by quantitative real-time PCR assay, showing that the expression of SpA was repressed at the transcriptional level in these strains. Furthermore, ELISA assay showed that whole EM-resistant cell SpA content was significantly decreased. Therefore, it was considered that the suppression of surface SpA on the EM-resistant strain was due to regulated SpA production, and not dependent on the conformational change in SpA molecule expression through cell wall thickening. These results strongly suggest that suppressed SpA distribution on the EM-resistant S. aureus is a phenotypical characteristic in these strains.
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Affiliation(s)
- Kanako Okabe
- Department of Medical Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki, Okayama, 701-0193, Japan.
| | - Kumiko Chikasue
- Department of Medical Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki, Okayama, 701-0193, Japan
| | - Keiji Murakami
- Department of Clinical Nutrition, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki, Okayama, 701-0193, Japan
| | - Nobuaki Matsuda
- Electron Microscope Center, Kawasaki Medical School, 577 Matsushima, Kurashiki, Okayama, Japan
| | - Sakuo Yamada
- Department of Medical Technology, Kawasaki University of Medical Welfare, 288 Matsushima, Kurashiki, Okayama, 701-0193, Japan
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Hong X, Zhou S, Dai X, Xie D, Cai Y, Zhao G, Li B. Molecular typing and characterization of Staphylococcus aureus isolates from burn wound infections in Fujian, China. Front Microbiol 2023; 14:1236497. [PMID: 37799609 PMCID: PMC10547878 DOI: 10.3389/fmicb.2023.1236497] [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: 06/07/2023] [Accepted: 08/30/2023] [Indexed: 10/07/2023] Open
Abstract
Background Staphylococcus aureus (S. aureus) is the most common causative agent of burn wound infection, that often leads to high morbidity and mortality. However, there is not enough knowledge about the molecular epidemiology and antimicrobial susceptibility of S. aureus isolates from burn wound infections in Fujian, China. Methods Between 2016 and 2021, 90 S. aureus isolates were collected from burn wound infections in Fujian, China, including 59 methicillin-resistant (MRSA) strains and 31 methicillin-susceptible (MSSA) strains. These were investigated for molecular characteristics, virulence genes, biofilms, and antimicrobial susceptibility. All the isolates were genotyped by multilocus sequence typing (MLST), spa typing, agr typing, and SCCmec typing. Conventional PCR was performed for the detection of virulence genes. Biofilm formation capacity was assessed by tissue culture plate assay (TCP). The antimicrobial susceptibility of the isolates was evaluated using the dilution method. Results In total, 37 sequence types (ST) and 34 Staphylococcal protein A (spa) types (including a new type named spa-t20720) were identified based on multilocus sequence typing (MLST) and spa typing, respectively. CC8-ST239-t030-agrI-SCCmecIII (57.6%,34/59) and CC7-ST7-t091-agrI (16.1%, 5/31) represented the main clone of MRSA and MSSA isolates, respectively. Antibiotic susceptibility testing identified a significant difference in resistance rates between ST239 and non-ST239 isolates (p < 0.05). Twelve virulence genes were detected, of which the most common were icaA and icaD (both 100%), followed by icaB and icaC (both 96.7%), icaR (95.6%), lukED (81.1%), lukAB (62.2%), pvl (50%), hlgBC (26.7%), and eta (4.4%). Moreover, lukAB, hlgBC, agrI, and agrIII were significantly correlated with burn severity (p < 0.05). MRSA isolates were less likely, compared with MSSA isolates, to carry pvl, lukAB, and hlgBC (p < 0.05). A new spa type, t20720, was identified that contains pvl, lukED, lukAB, hlgBC, icaA, icaB, icaC, icaD, and icaR genes and has strong biofilm formation ability. Conclusion CC8-ST239-t030-agrI-SCCmecIII and CC7-ST-7-t091-agrI were the prevalent molecular signatures of MRSA and MSSA isolates from burn wound infections in Fujian, China, respectively. The newly identified spa-t20720 isolate, which carries a wide range of virulence genes and has strong biofilm formation ability, requires special clinical attention.
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Affiliation(s)
- Xiaolan Hong
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fujian, China
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Shaobo Zhou
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Xubo Dai
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Dandan Xie
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Yuanyuan Cai
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Guimei Zhao
- Department of Clinical Laboratory, The 910 Hospital of Joint Logistics Support Force of Chinese People's Liberation Army, Fujian, China
| | - Bin Li
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fujian, China
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Gabriele F, Palerma M, Ippoliti R, Angelucci F, Pitari G, Ardini M. Recent Advances on Affibody- and DARPin-Conjugated Nanomaterials in Cancer Therapy. Int J Mol Sci 2023; 24:ijms24108680. [PMID: 37240041 DOI: 10.3390/ijms24108680] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 05/06/2023] [Accepted: 05/08/2023] [Indexed: 05/28/2023] Open
Abstract
Affibodies and designed ankyrin repeat proteins (DARPins) are synthetic proteins originally derived from the Staphylococcus aureus virulence factor protein A and the human ankyrin repeat proteins, respectively. The use of these molecules in healthcare has been recently proposed as they are endowed with biochemical and biophysical features heavily demanded to target and fight diseases, as they have a strong binding affinity, solubility, small size, multiple functionalization sites, biocompatibility, and are easy to produce; furthermore, impressive chemical and thermal stability can be achieved. especially when using affibodies. In this sense, several examples reporting on affibodies and DARPins conjugated to nanomaterials have been published, demonstrating their suitability and feasibility in nanomedicine for cancer therapy. This minireview provides a survey of the most recent studies describing affibody- and DARPin-conjugated zero-dimensional nanomaterials, including inorganic, organic, and biological nanoparticles, nanorods, quantum dots, liposomes, and protein- and DNA-based assemblies for targeted cancer therapy in vitro and in vivo.
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Affiliation(s)
- Federica Gabriele
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Marta Palerma
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Rodolfo Ippoliti
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Francesco Angelucci
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Giuseppina Pitari
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
| | - Matteo Ardini
- Department of Life, Health and Environmental Sciences, University of L'Aquila, 67100 L'Aquila, Italy
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Staphylococcus aureus Host Spectrum Correlates with Methicillin Resistance in a Multi-Species Ecosystem. Microorganisms 2023; 11:microorganisms11020393. [PMID: 36838358 PMCID: PMC9964919 DOI: 10.3390/microorganisms11020393] [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: 11/17/2022] [Revised: 01/23/2023] [Accepted: 01/25/2023] [Indexed: 02/08/2023] Open
Abstract
Although antibiotic resistance is a major issue for both human and animal health, very few studies have investigated the role of the bacterial host spectrum in its dissemination within natural ecosystems. Here, we assessed the prevalence of methicillin resistance among Staphylococcus aureus (MRSA) isolates from humans, non-human primates (NHPs), micromammals and bats in a primatology center located in southeast Gabon, and evaluated the plausibility of four main predictions regarding the acquisition of antibiotic resistance in this ecosystem. MRSA strain prevalence was much higher in exposed species (i.e., humans and NHPs which receive antibiotic treatment) than in unexposed species (micromammals and bats), and in NHP species living in enclosures than those in captivity-supporting the assumption that antibiotic pressure is a risk factor in the acquisition of MRSA that is reinforced by the irregularity of drug treatment. In the two unexposed groups of species, resistance prevalence was high in the generalist strains that infect humans or NHPs, supporting the hypothesis that MRSA strains diffuse to wild species through interspecific transmission of a generalist strain. Strikingly, the generalist strains that were not found in humans showed a higher proportion of MRSA strains than specialist strains, suggesting that generalist strains present a greater potential for the acquisition of antibiotic resistance than specialist strains. The host spectrum is thus a major component of the issue of antibiotic resistance in ecosystems where humans apply strong antibiotic pressure.
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In Silico Genome-Scale Analysis of Molecular Mechanisms Contributing to the Development of a Persistent Infection with Methicillin-Resistant Staphylococcus aureus (MRSA) ST239. Int J Mol Sci 2022; 23:ijms232416086. [PMID: 36555727 PMCID: PMC9781258 DOI: 10.3390/ijms232416086] [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: 10/30/2022] [Revised: 12/05/2022] [Accepted: 12/11/2022] [Indexed: 12/23/2022] Open
Abstract
The increasing frequency of isolation of methicillin-resistant Staphylococcus aureus (MRSA) limits the chances for the effective antibacterial therapy of staphylococcal diseases and results in the development of persistent infection such as bacteremia and osteomyelitis. The aim of this study was to identify features of the MRSAST239 0943-1505-2016 (SA943) genome that contribute to the formation of both acute and chronic musculoskeletal infections. The analysis was performed using comparative genomics data of the dominant epidemic S. aureus lineages, namely ST1, ST8, ST30, ST36, and ST239. The SA943 genome encodes proteins that provide resistance to the host's immune system, suppress immunological memory, and form biofilms. The molecular mechanisms of adaptation responsible for the development of persistent infection were as follows: amino acid substitution in PBP2 and PBP2a, providing resistance to ceftaroline; loss of a large part of prophage DNA and restoration of the nucleotide sequence of beta-hemolysin, that greatly facilitates the escape of phagocytosed bacteria from the phagosome and formation of biofilms; dysfunction of the AgrA system due to the presence of psm-mec and several amino acid substitutions in the AgrC; partial deletion of the nucleotide sequence in genomic island vSAβ resulting in the loss of two proteases of Spl-operon; and deletion of SD repeats in the SdrE amino acid sequence.
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8
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Effect of solution condition on the binding behaviors of monoclonal antibody and fusion protein therapeutics in Protein A chromatography. J Chromatogr A 2022; 1686:463652. [DOI: 10.1016/j.chroma.2022.463652] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 11/12/2022] [Accepted: 11/14/2022] [Indexed: 11/18/2022]
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SpAD Biofunctionalized Cellulose Acetate Scaffolds Inhibit Staphylococcus aureus Adherence in a Coordinating Function with the von Willebrand A1 Domain (vWF A1). J Funct Biomater 2022; 13:jfb13010021. [PMID: 35225984 PMCID: PMC8883972 DOI: 10.3390/jfb13010021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/07/2022] [Accepted: 02/11/2022] [Indexed: 12/02/2022] Open
Abstract
Staphylococcus aureus is one of the major pathogens causing and spreading hospital acquired infections. Since it is highly resistant to new generation antibiotics, novel strategies have to be developed such as the construction of biofunctionalized non-adherent surfaces that will prevent its tethering and subsequent spread in the hospital environment. In this frame, the domain D of protein A (SpAD) of S. aureus has been immobilized onto cellulose acetate scaffolds by using the streptavidin/biotin interaction, in order to study its interaction with the A1 domain of von Willebrand factor (vWF A1), a protein essential for hemostasis, found in human plasma. Subsequently, the biofunctionalized cellulose acetate scaffolds were incubated with S. aureus in the presence and absence of vWF A1 at different time periods and their potential to inhibit S. aureus growth was studied with scanning electron microscopy (SEM). The SpAD biofunctionalized scaffolds perceptibly ameliorated the non-adherent properties of the material, and in particular, the interaction between SpAD and vWF A1 effectively inhibited the growth of S. aureus. Thus, the exhibition of significant non-adherent properties of scaffolds addresses their potential use for covering medical equipment, implants, and stents.
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Suffian IFBM, Al-Jamal KT. Bioengineering of virus-like particles as dynamic nanocarriers for in vivo delivery and targeting to solid tumours. Adv Drug Deliv Rev 2022; 180:114030. [PMID: 34736988 DOI: 10.1016/j.addr.2021.114030] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2021] [Revised: 09/16/2021] [Accepted: 10/27/2021] [Indexed: 12/12/2022]
Abstract
Virus-like particles (VLPs) are known as self-assembled, non-replicative and non-infectious protein particles, which imitate the formation and structure of original wild type viruses, however, lack the viral genome and/or their fragments. The capacity of VLPs to encompass small molecules like nucleic acids and others has made them as novel vessels of nanocarriers for drug delivery applications. In addition, VLPs surface have the capacity to achieve variation of the surface display via several modification strategies including genetic modification, chemical modification, and non-covalent modification. Among the VLPs nanocarriers, Hepatitis B virus core (HBc) particles have been the most encouraging candidate. HBc particles are hollow nanoparticles in the range of 30-34 nm in diameter and 7 nm thick envelopes, consisting of 180 or 240 copies of identical polypeptide monomer. They also employ a distinctive position among the VLPs carriers due to the high-level synthesis, which serves as a strong protective capsid shell and efficient self-assembly properties. This review highlights on the bioengineering of HBc particles as dynamic nanocarriers for in vivo delivery and specific targeting to solid tumours.
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Affiliation(s)
- Izzat F B M Suffian
- Department of Pharmaceutical Technology, Kulliyyah of Pharmacy, International Islamic University Malaysia (Kuantan Campus), Jalan Sultan Ahmad Shah, Bandar Indera Mahkota, 25200 Kuantan, Pahang, Malaysia.
| | - Khuloud T Al-Jamal
- Institute of Pharmaceutical Science, King's College London, Franklin-Wilkins Building, 150 Stamford Street, London SE1 9NH, UK.
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Patil U, Goyal A, Vu B, Liu Y, Maranholkar V, Kourentzi K, Briggs JM, Willson RC. Antibody mix-and-read assays based on fluorescence intensity probes. MAbs 2021; 13:1980178. [PMID: 34662534 PMCID: PMC8525972 DOI: 10.1080/19420862.2021.1980178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
Abstract
Antibodies and Fc fusion proteins are a rapidly growing class of pharmaceuticals. Cell culture and purification process development and operation require frequent measurement of product concentrations, commonly by complex enzyme-linked immunosorbent assay and high-performance liquid chromatography methods. Here we report a fast (<30 s), and simple antibody Fc assay based on mix-and-read reporting by fluorescence emission. A soluble fluorescein-labeled Fc-affinity reporter produced by standard peptide synthesis is mixed with an Fc-containing sample to produce an immediate shift in both fluorescence polarization and intensity, compatible with on- and at-line measurements and microbioreactor monitoring. We observed significant shifts in fluorescence intensity in Chinese hamster ovary cell culture fluid spiked with IgG and detected an adalimumab biosimilar down to 100 ng/mL (10-4 g/L), despite the interferents in the complex sample matrix. Neither the fluorescence polarization nor the fluorescence intensity assay is significantly affected by the addition of clarified lysate of 2 million CHO-k1 cells/mL, suggesting applicability even to cultures of low viability. Biochemical and molecular docking approaches suggest that the fluorescence intensity enhancement is caused by changes in the fluorophore's local microenvironment upon binding to IgG Fc, especially by interactions with Fc His433.Abbreviations: CCF: Cell Culture Fluid; CHO: Chinese Hamster Ovary cells; ELISA: Enzyme Linked Immunosorbent Assay; Fc: Fragment Crystallizable of antibody; HPLC: High-Performance Liquid Chromatography; HPβCD: hydroxypropyl-β-cyclodextrin; IgG: ImmunoglobulinG; mAb: Monoclonal Antibody; PBS: Phosphate-Buffered Saline; PDB: Protein Data Bank; SpA: Staphylococcal protein A; SpG: Staphylococcal protein G.
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Affiliation(s)
- Ujwal Patil
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Atul Goyal
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA
| | - Binh Vu
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA
| | - Yanyun Liu
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Vijay Maranholkar
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA
| | - Katerina Kourentzi
- William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA
| | - James M Briggs
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA.,William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA
| | - Richard C Willson
- Department of Biology and Biochemistry, University of Houston, Houston, Texas, USA.,William A. Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, USA.,Escuela De Medicina Y Ciencias De La Salud TecSalud, Monterrey, Nuevo León, Mexico
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12
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Shi M, Willing SE, Kim HK, Schneewind O, Missiakas D. Peptidoglycan Contribution to the B Cell Superantigen Activity of Staphylococcal Protein A. mBio 2021; 12:e00039-21. [PMID: 33879590 PMCID: PMC8092194 DOI: 10.1128/mbio.00039-21] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Accepted: 03/17/2021] [Indexed: 11/20/2022] Open
Abstract
Staphylococcus aureus causes reiterative and chronic persistent infections. This can be explained by the formidable ability of this pathogen to escape immune surveillance mechanisms. Cells of S. aureus display the abundant staphylococcal protein A (SpA). SpA binds to immunoglobulin (Ig) molecules and coats the bacterial surface to prevent phagocytic uptake. SpA also binds and cross-links variable heavy 3 (VH3) idiotype (IgM) B cell receptors, promoting B cell expansion and the secretion of nonspecific VH3-IgM via a mechanism requiring CD4+ T cell help. SpA binding to antibodies is mediated by the N-terminal Ig-binding domains (IgBDs). The so-called region X, uncharacterized LysM domain, and C-terminal LPXTG sorting signal for peptidoglycan attachment complete the linear structure of the protein. Here, we report that both the LysM domain and the LPXTG motif sorting signal are required for the B cell superantigen activity of SpA in a mouse model of infection. SpA molecules purified from staphylococcal cultures are sufficient to exert B cell superantigen activity and promote immunoglobulin secretion as long as they carry intact LysM and LPXTG motif domains with bound peptidoglycan fragments. The LysM domain binds the glycan chains of peptidoglycan fragments, whereas the LPXTG motif is covalently linked to wall peptides lacking glycan. These findings emphasize the complexity of SpA interactions with B cell receptors.IMPORTANCE The LysM domain is found in all kingdoms of life. While their function in mammals is not known, LysM domains of bacteria and their phage parasites are associated with enzymes that cleave or remodel peptidoglycan. Plants recognize microbe-associated molecular patterns such as chitin via receptors endowed with LysM-containing ectodomains. In plants, such receptors play equally important roles in defense and symbiosis signaling. SpA of S. aureus carries a LysM domain that binds glycan strands of peptidoglycan to influence defined B cell responses that divert pathogen-specific adaptive immune responses.
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Affiliation(s)
- Miaomiao Shi
- Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Lemont, Illinois, USA
| | | | - Hwan Keun Kim
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
| | - Dominique Missiakas
- Howard Taylor Ricketts Laboratory, Argonne National Laboratory, Lemont, Illinois, USA
- Department of Microbiology, University of Chicago, Chicago, Illinois, USA
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Mohammed KAS, Abdulkareem ZH, Alzaalan AR, Yaqoob AK. Spa typing of Staphylococcus aureus Isolated from Clinical Specimens from Outpatients in Iraq. Pol J Microbiol 2021; 70:79-85. [PMID: 33815529 PMCID: PMC8008756 DOI: 10.33073/pjm-2021-007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Revised: 01/18/2021] [Accepted: 01/19/2021] [Indexed: 12/28/2022] Open
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is notorious as a hospital superbug and a problematic pathogen among communities. The incidence of MRSA has substantially increased over time in Iraq. The aim of this study was to determine the prevalence and spa types of MRSA isolates from outpatients or patients upon admission into hospitals. Various biochemical tests identified S. aureus isolates, and then this identification was confirmed by PCR using species-specific 16S rRNA primer pairs. Antibiotic susceptibility was determined against methicillin, oxacillin, and vancomycin using the disk diffusion method. Vancomycin MIC was detected by VITEK 2 compact system. All the identified isolates were screened for the presence of mecA and lukS-PV-lukF-PV genes; 36 of them were subjected to spa typing-based PCR. Out of 290 clinical samples, 65 (22.4%) were S. aureus, of which 62 (95.4%) strains were resistant to oxacillin and methicillin. Except for two isolates, all MRSA isolates were mecA positive. One of the three MSSA isolates was mecA positive. Five strains were resistant to vancomycin. Fourteen (21.5%) isolates were positive for the presence of lukS-PV-lukF-PV genes. Spa typing of 36 S. aureus isolates revealed eleven different spa types, t304 (30.3%), t307 (19.4%), t346 (8.3%), t044 (8.3%), t15595 (8.3%), t386 (5.5%), t5475 (5.5%), t17928 (2.8%), t14870 (2.8%), t021 (2.8%), and t024 (2.8%). These findings could be useful for assessing the genetic relatedness of strains in the region for epidemiological and monitoring purposes, which would be essential to limiting the spread of MRSA.
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Affiliation(s)
- Khairallah A S Mohammed
- Department of Medical Lab Technology, College of Health and Medical Technology, Southern Technical University, Basrah, Iraq
| | - Zahraa H Abdulkareem
- Department of Medical Lab Technology, College of Health and Medical Technology, Southern Technical University, Basrah, Iraq
| | - Ayoob R Alzaalan
- Department of Medical Lab Technology, College of Health and Medical Technology, Southern Technical University, Basrah, Iraq
| | - Amel K Yaqoob
- Department of Medical Lab Technology, College of Health and Medical Technology, Southern Technical University, Basrah, Iraq
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14
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Cruz AR, Boer MAD, Strasser J, Zwarthoff SA, Beurskens FJ, de Haas CJC, Aerts PC, Wang G, de Jong RN, Bagnoli F, van Strijp JAG, van Kessel KPM, Schuurman J, Preiner J, Heck AJR, Rooijakkers SHM. Staphylococcal protein A inhibits complement activation by interfering with IgG hexamer formation. Proc Natl Acad Sci U S A 2021; 118:e2016772118. [PMID: 33563762 PMCID: PMC7896290 DOI: 10.1073/pnas.2016772118] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Immunoglobulin (Ig) G molecules are essential players in the human immune response against bacterial infections. An important effector of IgG-dependent immunity is the induction of complement activation, a reaction that triggers a variety of responses that help kill bacteria. Antibody-dependent complement activation is promoted by the organization of target-bound IgGs into hexamers that are held together via noncovalent Fc-Fc interactions. Here we show that staphylococcal protein A (SpA), an important virulence factor and vaccine candidate of Staphylococcus aureus, effectively blocks IgG hexamerization and subsequent complement activation. Using native mass spectrometry and high-speed atomic force microscopy, we demonstrate that SpA blocks IgG hexamerization through competitive binding to the Fc-Fc interaction interface on IgG monomers. In concordance, we show that SpA interferes with the formation of (IgG)6:C1q complexes and prevents downstream complement activation on the surface of S. aureus. Finally, we demonstrate that IgG3 antibodies against S. aureus can potently induce complement activation and opsonophagocytic killing even in the presence of SpA. Together, our findings identify SpA as an immune evasion protein that specifically blocks IgG hexamerization.
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Affiliation(s)
- Ana Rita Cruz
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Maurits A den Boer
- Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Jürgen Strasser
- Nano Structuring and Bio-Analytics Group, TIMed Center, University of Applied Sciences Upper Austria, 4020 Linz, Austria
| | - Seline A Zwarthoff
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | | | - Carla J C de Haas
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Piet C Aerts
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Guanbo Wang
- Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CH Utrecht, The Netherlands
- School of Chemistry and Materials Science, Nanjing Normal University, 210023 Nanjing, China
| | | | | | - Jos A G van Strijp
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | - Kok P M van Kessel
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands
| | | | - Johannes Preiner
- Nano Structuring and Bio-Analytics Group, TIMed Center, University of Applied Sciences Upper Austria, 4020 Linz, Austria
| | - Albert J R Heck
- Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, Utrecht University, 3584 CH Utrecht, The Netherlands
| | - Suzan H M Rooijakkers
- Medical Microbiology, University Medical Center Utrecht, Utrecht University, 3584 CX Utrecht, The Netherlands;
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15
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Tissues: the unexplored frontier of antibody mediated immunity. Curr Opin Virol 2021; 47:52-67. [PMID: 33581646 DOI: 10.1016/j.coviro.2021.01.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Revised: 01/01/2021] [Accepted: 01/05/2021] [Indexed: 12/14/2022]
Abstract
Pathogen-specific immunity evolves in the context of the infected tissue. However, current immune correlates analyses and vaccine efficacy metrics are based on immune functions from peripheral cells. Less is known about tissue-resident mechanisms of immunity. While antibodies represent the primary correlate of immunity following most clinically approved vaccines, how antibodies interact with localized, compartment-specific immune functions to fight infections, remains unclear. Emerging data demonstrate a unique community of immune cells that reside within different tissues. These tissue-specific immunological communities enable antibodies to direct both expected and unexpected local attack strategies to control, disrupt, and eliminate infection in a tissue-specific manner. Defining the full breadth of antibody effector functions, how they selectively contribute to control at the site of infection may provide clues for the design of next-generation vaccines able to direct the control, elimination, and prevention of compartment specific diseases of both infectious and non-infectious etiologies.
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16
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Wetterhall M, Ander M, Björkman T, Musunuri S, Palmgren R, Rodrigo G. Investigation of alkaline effects on Protein A affinity ligands and resins using high resolution mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2021; 1162:122473. [PMID: 33370685 DOI: 10.1016/j.jchromb.2020.122473] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Revised: 10/28/2020] [Accepted: 11/21/2020] [Indexed: 10/22/2022]
Abstract
In this study, the enhanced alkaline stability of Protein A ligands and resins designed by protein engineering approaches is demonstrated. High throughput PreDictor™ plates were used to evaluate and compare the human Immunoglobulin G (IgG) static binding capacities (SBC) of MabSelect SuRe™ and MabSelect™ PrismA affinity chromatography (AC) resins after continuous incubation in 0.1-2.0 M NaOH for 1-72 h. The alkaline effect on the Protein A affinity ligand was studied by high resolution mass spectrometry (MS). The IgG binding capacity of the investigated AC resins show expected declining trends with increasing NaOH concentrations and incubation times. The decrease is larger for MabSelect SuRe than for MabSelect PrismA and occur at lower NaOH concentrations. MabSelect SuRe display high remaining binding capacity even after 72 h continuous incubation in 0.1 M NaOH, while higher concentrations induce an accentuated decline with incubation time. The MabSelect PrismA resin shows almost no effect on the binding capacity even after 72 h incubation in 0.5 M NaOH. Decline in capacity is first observed after 48 h incubation in 1.0 M NaOH, thus displaying the extreme alkaline stability of the PrismA affinity ligand. The MS analysis of the ligands, including a Protein A single B-domain, SuRe-domain and PrismA-domain clearly illustrate the increasing alkaline stability (B-domain < SuRe < PrismA) as the ligand has been refined using a protein engineering approach. Deamidation and ligand degradation could be monitored in relation to NaOH incubation conditions. Enzymatic digestion of MabSelect SuRe and MabSelect PrismA resins after alkaline incubation and LC-MS/MS peptide mapping facilitates identification and quantification of specific deamidation sites on the affinity ligand.
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Affiliation(s)
| | - Mats Ander
- Cytiva, BioProcess, Björkgatan 30, SE-75184 Uppsala, Sweden
| | - Tomas Björkman
- Cytiva, BioProcess, Björkgatan 30, SE-75184 Uppsala, Sweden
| | | | | | - Gustav Rodrigo
- Cytiva, BioProcess, Björkgatan 30, SE-75184 Uppsala, Sweden
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17
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Population Analysis of Staphylococcus aureus Reveals a Cryptic, Highly Prevalent Superantigen SElW That Contributes to the Pathogenesis of Bacteremia. mBio 2020; 11:mBio.02082-20. [PMID: 33109757 PMCID: PMC7593966 DOI: 10.1128/mbio.02082-20] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Staphylococcus aureus is an important human and animal pathogen associated with an array of diseases, including life-threatening necrotizing pneumonia and infective endocarditis. The success of S. aureus as a pathogen has been linked in part to its ability to manipulate the host immune response through the secretion of toxins and immune evasion molecules. The staphylococcal superantigens (SAgs) have been studied for decades, but their role in S. aureus pathogenesis is not well understood, and an appreciation for how SAgs manipulate the host immune response to promote infection may be crucial for the development of novel intervention strategies. Here, we characterized a widely prevalent, previously cryptic, staphylococcal SAg, SElW, that contributes to the severity of S. aureus infections caused by an important epidemic clone of S. aureus CC398. Our findings add to the understanding of staphylococcal SAg diversity and function and provide new insights into the capacity of S. aureus to cause disease. Staphylococcal superantigens (SAgs) are a family of secreted toxins that stimulate T cell activation and are associated with an array of diseases in humans and livestock. Most SAgs produced by Staphylococcus aureus are encoded by mobile genetic elements, such as pathogenicity islands, bacteriophages, and plasmids, in a strain-dependent manner. Here, we carried out a population genomic analysis of >800 staphylococcal isolates representing the breadth of S. aureus diversity to investigate the distribution of all 26 identified SAg genes. Up to 14 SAg genes were identified per isolate with the most common gene selw (encoding a putative SAg, SElW) identified in 97% of isolates. Most isolates (62.5%) have a full-length open reading frame of selw with an alternative TTG start codon that may have precluded functional characterization of SElW to date. Here, we demonstrate that S. aureus uses the TTG start codon to translate a potent SAg SElW that induces Vβ-specific T cell proliferation, a defining feature of classical SAgs. SElW is the only SAg predicted to be expressed by isolates of the CC398 lineage, an important human and livestock epidemic clone. Deletion of selw in a representative CC398 clinical isolate, S. aureus NM001, resulted in complete loss of T cell mitogenicity in vitro, and in vivo expression of SElW by S. aureus increased the bacterial load in the liver during bloodstream infection of SAg-sensitive HLA-DR4 transgenic mice. Overall, we report the characterization of a novel, highly prevalent, and potent SAg that contributes to the pathogenesis of S. aureus infection.
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18
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Back SH, Eom HS, Lee HH, Lee GY, Park KT, Yang SJ. Livestock-associated methicillin-resistant Staphylococcus aureus in Korea: antimicrobial resistance and molecular characteristics of LA-MRSA strains isolated from pigs, pig farmers, and farm environment. J Vet Sci 2020; 21:e2. [PMID: 31940681 PMCID: PMC7000904 DOI: 10.4142/jvs.2020.21.e2] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 10/06/2019] [Accepted: 10/15/2019] [Indexed: 01/20/2023] Open
Abstract
The emergence of livestock-associated (LA)-methicillin-resistant Staphylococcus aureus (MRSA) in livestock animal has become a significant zoonotic concern. In the present study, we investigated nationwide prevalence of LA-MRSA across pork production chain including pig farms, slaughterhouses, and retail markets. A total of 40 MRSA strains were isolated during the investigation and the overall prevalence of MRSA was 3.4% (n = 37), 0.6% (n = 2), and 0.4% (n = 1) in pig farms, slaughterhouses, and retail markets, respectively. Multilocus sequence typing analyses revealed that the 2 most significant clonal lineages in pork production chain in Korea were ST398 (n = 25) and ST541 (n = 6). All of the 40 MRSA isolates were further characterized to investigate key genotypic and phenotypic correlates associated with the emergence and spread of clonal complex 398 (CC398; ST398, and ST541) LA-MRSA. Although the prevalence of swine-associated MRSA was still relatively low and mostly restricted to pig farms, multidrug-resistant CC398 LA-MRSA isolates with new spa types (t18102 and t18103) were identified as a major clonal lineage. The CC398 LA-MRSA strains tended to exhibit increased levels of multiple drug resistance (MDR) phenotype compared with non-CC398 MRSA strains. Of note, in comparison with non-CC398 MRSA isolates, CC398 LA-MRSA isolates exhibited significantly enhanced tetracycline (TET) and zinc resistance. These findings suggested that co-selection pressure associated with MDR phenotype, especially TET resistance, and zinc resistance may have played a significant role in the emergence and persistence of CC398 LA-MRSA in pig farms in Korea.
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Affiliation(s)
- Seung Hyun Back
- Department of Animal Science and Technology, School of Bioresources and Bioscience, Chung-Ang University, Anseong 17546, Korea
| | - Hong Sik Eom
- Department of Animal Science and Technology, School of Bioresources and Bioscience, Chung-Ang University, Anseong 17546, Korea
| | - Haeng Ho Lee
- Department of Animal Science and Technology, School of Bioresources and Bioscience, Chung-Ang University, Anseong 17546, Korea
| | - Gi Yong Lee
- Department of Animal Science and Technology, School of Bioresources and Bioscience, Chung-Ang University, Anseong 17546, Korea
| | - Kun Taek Park
- Department of Biotechnology, Inje University, Gimhae 50834, Korea
| | - Soo Jin Yang
- Department of Animal Science and Technology, School of Bioresources and Bioscience, Chung-Ang University, Anseong 17546, Korea.
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19
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Chen W, Shen B, Sun X. Analysis of Progress and Challenges of EGFR-Targeted Molecular Imaging in Cancer With a Focus on Affibody Molecules. Mol Imaging 2019; 18:1536012118823473. [PMID: 30799684 PMCID: PMC6348515 DOI: 10.1177/1536012118823473] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Epidermal growth factor receptor (EGFR)-targeted cancer therapy requires an accurate estimation of EGFR expression in tumors to identify responsive patients, monitor therapeutic effect, and estimate prognosis. The EGFR molecular imaging is an optimal method for evaluating EGFR expression in vivo accurately and noninvasively. In this review, we discuss the recent advances in EGFR-targeted molecular imaging in cancer, with a special focus on the development of imaging agents, including epidermal growth factor (EGF) ligand, monoclonal antibodies, antibody fragments, Affibody, and small molecules. Each substrate or probe, whether it is an endogenous ligand, antibody, peptide, or small molecule labeled with fluorochrome or radionuclide, has unique advantages and limitations. Antibody-based probes have high affinity but a long metabolic cycle and therefore offer poor imaging quality. Affibody molecules promise to surpass antibody-based probes due to their small size, stable chemical properties, and high affinity to the target. Small-molecule probes are safe, have favorable pharmacokinetics, and show high affinity and specificity, in addition to having an ideal size, but are inadequate for delayed imaging after injection due to their fast clearance.
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Affiliation(s)
- Weizhi Chen
- 1 Molecular Imaging Research Center, Harbin Medical University, Heilongjiang, China.,2 TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Heilongjiang, China
| | - Baozhong Shen
- 1 Molecular Imaging Research Center, Harbin Medical University, Heilongjiang, China.,2 TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Heilongjiang, China
| | - Xilin Sun
- 1 Molecular Imaging Research Center, Harbin Medical University, Heilongjiang, China.,2 TOF-PET/CT/MR Center, The Fourth Hospital of Harbin Medical University, Heilongjiang, China
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20
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Pourshohod A, Jamalan M, Zeinali M, Ghanemi M, kheirollah A. Enhancement of X-ray radiotherapy by specific delivery of ZHER2 affibody-conjugated gold nanoparticles to HER2-positive malignant cells. J Drug Deliv Sci Technol 2019. [DOI: 10.1016/j.jddst.2019.05.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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21
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Antibody Binding Heterogeneity of Protein A Resins. Biotechnol J 2019; 14:e1800632. [DOI: 10.1002/biot.201800632] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Revised: 03/08/2019] [Indexed: 01/25/2023]
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22
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Binding of Staphylococcus aureus Protein A to von Willebrand Factor Is Regulated by Mechanical Force. mBio 2019; 10:mBio.00555-19. [PMID: 31040240 PMCID: PMC6495375 DOI: 10.1128/mbio.00555-19] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Staphylococcus aureus protein A (SpA) binds to von Willebrand factor (vWF) under flow. While vWF binding to SpA plays a role in S. aureus adherence to platelets and endothelial cells under shear stress, the molecular basis of this stress-dependent interaction has not yet been elucidated. Here we show that the SpA-vWF interaction is regulated by a new force-dependent mechanism. The results suggest that mechanical extension of vWF may lead to the exposure of a high-affinity cryptic SpA-binding site, consistent with the shear force-controlled functions of vWF. Moreover, strong binding may be promoted by force-induced structural changes in the SpA domains. This study highlights the role of mechanoregulation in controlling the adhesion of S. aureus and shows promise for the design of small inhibitors capable of blocking colonization under high shear stress. Binding of Staphylococcus aureus to the large plasma glycoprotein von Willebrand factor (vWF) is controlled by hydrodynamic flow conditions. Currently, we know little about the molecular details of this shear-stress-dependent interaction. Using single-molecule atomic force microscopy, we demonstrate that vWF binds to the S. aureus surface protein A (SpA) via a previously undescribed force-sensitive mechanism. We identify an extremely strong SpA-vWF interaction, capable of withstanding forces of ∼2 nN, both in laboratory and in clinically relevant methicillin-resistant S. aureus (MRSA) strains. Strong bonds are activated by mechanical stress, consistent with flow experiments revealing that bacteria adhere in larger amounts to vWF surfaces when the shear rate is increased. We suggest that force-enhanced adhesion may involve conformational changes in vWF. Under force, elongation of vWF may lead to the exposure of a high-affinity cryptic SpA-binding site to which bacteria firmly attach. In addition, force-induced structural changes in the SpA domains may also promote strong, high-affinity binding. This force-regulated interaction might be of medical importance as it may play a role in bacterial adherence to platelets and to damaged blood vessels.
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23
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Rigi G, Ghaedmohammadi S, Ahmadian G. A comprehensive review on staphylococcal protein A (SpA): Its production and applications. Biotechnol Appl Biochem 2019; 66:454-464. [PMID: 30869160 DOI: 10.1002/bab.1742] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 03/13/2019] [Indexed: 01/09/2023]
Abstract
The Staphylococcus aureus protein A (SpA) can be obtained through the culture of wild-type S. aureus and also as a recombinant protein in safe bacterial hosts. Several methods have been used to purify SpA among which ion-exchange chromatography, affinity chromatography, gel filtration, and per aqueous liquid chromatography (PALC) are common. SpA has a wide range of biochemical, biotechnological, and medical applications and is most commonly used in test methods such as immunoprecipitation, enzyme-linked immunosorbent assay, and Western blotting. SpA has also been widely utilized in pharmaceutical applications to bind to immune complexes and serum immunoglobulins. SpA also directly binds to the B-cells preventing initiation of infectious diseases as well as having a role in the development of various autoimmune diseases. This review considers different applications of SpA in biotechnology and its novel clinical application for effective treatment of autoimmune diseases. It also discusses various strategies for expression and purification of the SpA including types of column chromatography that are commonly used in protein purification and developing SpA surface display technologies. Finally, this review highlights the potential and novel applications of SpA immobilization, SpA typing, protein engineering for further development of immunological and biochemical research, and also application of SpA as a diagnostic biosensor.
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Affiliation(s)
- Garshasb Rigi
- Department of Genetics, Faculty of Basic Science, Shahrekord University, Shahrekord, 881 863 4141, Iran.,Department of Industrial Biotechnology, Research Institute of Biotechnology, Shahrekord University, Shahrekord, Iran
| | - Samira Ghaedmohammadi
- Department of Cellular and Molecular Biology, Estahban Higher Education Center, Estahban, Iran
| | - Gholamreza Ahmadian
- Associate Professor, Department of Industrial and Environmental Biotechnology, National Institute of Genetic Engineering and Biotechnology (NIGEB), Tehran, Iran
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24
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Schneewind O, Missiakas D. Sortases, Surface Proteins, and Their Roles in Staphylococcus aureus Disease and Vaccine Development. Microbiol Spectr 2019; 7:10.1128/microbiolspec.PSIB-0004-2018. [PMID: 30737913 PMCID: PMC6386163 DOI: 10.1128/microbiolspec.psib-0004-2018] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Indexed: 12/27/2022] Open
Abstract
Sortases cleave short peptide motif sequences at the C-terminal end of secreted surface protein precursors and either attach these polypeptides to the peptidoglycan of Gram-positive bacteria or promote their assembly into pilus structures that are also attached to peptidoglycan. Sortase A, the enzyme first identified in the human pathogen Staphylococcus aureus, binds LPXTG motif sorting signals, cleaves between threonine (T) and glycine (G) residues, and forms an acyl enzyme between its active-site cysteine thiol and the carboxyl group of threonine (T). Sortase A acyl enzyme is relieved by the nucleophilic attack of the cross bridge amino group within lipid II, thereby generating surface protein linked to peptidoglycan precursor. Such products are subsequently incorporated into the cell wall envelope by enzymes of the peptidoglycan synthesis pathway. Surface proteins linked to peptidoglycan may be released from the bacterial envelope to diffuse into host tissues and fulfill specific biological functions. S. aureus sortase A is essential for host colonization and for the pathogenesis of invasive diseases. Staphylococcal sortase-anchored surface proteins fulfill key functions during the infectious process, and vaccine-induced antibodies targeting surface proteins may provide protection against S. aureus. Alternatively, small-molecule inhibitors of sortase may be useful agents for the prevention of S. aureus colonization and invasive disease.
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Affiliation(s)
- Olaf Schneewind
- Department of Microbiology, University of Chicago, Chicago, IL 60637
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25
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Versatile Protein-A Coated Photoelectric Immunosensors with a Purple-Membrane Monolayer Transducer Fabricated by Affinity-Immobilization on a Graphene-Oxide Complexed Linker and by Shear Flow. SENSORS 2018; 18:s18124493. [PMID: 30567418 PMCID: PMC6308460 DOI: 10.3390/s18124493] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2018] [Revised: 12/06/2018] [Accepted: 12/17/2018] [Indexed: 01/22/2023]
Abstract
Bacteriorhodopsin-embedded purple membranes (PM) have been demonstrated to be a sensitive photoelectric transducer for microbial detection. To efficiently prepare versatile BR-based immunosensors with protein A as antibody captures, a large, high-coverage, and uniformly oriented PM monolayer was fabricated on an electrode as an effective foundation for protein A conjugation through bis-NHS esters, by first affinity-coating biotinylated PM on an aminated surface using a complex of oxidized avidin and graphene oxide as the planar linker and then washing the coating with a shear flow. Three different polyclonal antibodies, each against Escherichia coli, Lactobacillus acidophilus, and Streptococcus mutans, respectively, were individually, effectively and readily adsorbed on the protein A coated electrodes, leading to selective and sensitive quantitative detection of their respective target cells in a single step without any labeling. A single-cell detection limit was achieved for the former two cells. AFM, photocurrent, and Raman analyses all displayed each fabricated layer as well as the captured bacteria, with AFM particularly revealing the formation of a massive continuous PM monolayer on aminated mica. The facile cell-membrane monolayer fabrication and membrane surface conjugation techniques disclosed in this study may be widely applied to the preparation of different biomembrane-based biosensors.
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26
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L Silva G, Plewka J, Lichtenegger H, Dias-Cabral AC, Jungbauer A, Tscheließnig R. The pearl necklace model in protein A chromatography: Molecular mechanisms at the resin interface. Biotechnol Bioeng 2018; 116:76-86. [PMID: 30252938 PMCID: PMC6587469 DOI: 10.1002/bit.26843] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 09/17/2018] [Accepted: 09/21/2018] [Indexed: 01/08/2023]
Abstract
Staphylococcal protein A chromatography is an established core technology for monoclonal antibody purification and capture in the downstream processing. MabSelect SuRe involves a tetrameric chain of a recombinant form of the B domain of staphylococcal protein A, called the Z-domain. Little is known about the stoichiometry, binding orientation, or preferred binding. We analyzed small-angle X-ray scattering data of the antibody-protein A complex immobilized in an industrial highly relevant chromatographic resin at different antibody concentrations. From scattering data, we computed the normalized radial density distributions. We designed three-dimensional (3D) models with protein data bank crystallographic structures of an IgG1 (the isoform of trastuzumab, used here; Protein Data Bank: 1HZH) and the staphylococcal protein A B domain (the native form of the recombinant structure contained in MabSelect SuRe resin; Protein Data Bank: 1BDD). We computed different binding conformations for different antibody to protein A stoichiometries (1:1, 2:1, and 3:1) and compared the normalized radial density distributions computed from 3D models with those obtained from the experimental data. In the linear range of the isotherm we favor a 1:1 ratio, with the antibody binding to the outer domains in the protein A chain at very low and high concentrations. In the saturation region, a 2:1 ratio is more likely to occur. A 3:1 stoichiometry is excluded because of steric effects.
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Affiliation(s)
- Goncalo L Silva
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Department of Chemistry, University of Beira Interior, Covilhã, Portugal.,Department of Biotechnology, Austrian Centre of Industrial Biotechnology, Vienna, Austria
| | - Jacek Plewka
- Department of Biotechnology, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Material Science and Process Engineering, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Helga Lichtenegger
- Department of Biotechnology, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Material Science and Process Engineering, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Ana C Dias-Cabral
- CICS-UBI - Health Sciences Research Centre, University of Beira Interior, Covilhã, Portugal.,Department of Chemistry, University of Beira Interior, Covilhã, Portugal
| | - Alois Jungbauer
- Department of Biotechnology, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Rupert Tscheließnig
- Department of Biotechnology, Austrian Centre of Industrial Biotechnology, Vienna, Austria.,Department of Biotechnology, University of Natural Resources and Life Sciences, Vienna, Austria
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27
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Hierarchy of human IgG recognition within the Staphylococcus aureus immunome. Sci Rep 2018; 8:13296. [PMID: 30185867 PMCID: PMC6125462 DOI: 10.1038/s41598-018-31424-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Accepted: 08/17/2018] [Indexed: 11/24/2022] Open
Abstract
Staphylococcus aureus is an opportunistic pathogen that causes a range of serious infections associated with significant morbidity, by strains increasingly resistant to antibiotics. However, to date all candidate vaccines have failed to induce protective immune responses in humans. We need a more comprehensive understanding of the antigenic targets important in the context of human infection. To investigate infection-associated immune responses, patients were sampled at initial presentation and during convalescence from three types of clinical infection; skin and soft tissue infection (SSTI), prosthetic joint infection (PJI) and pediatric hematogenous osteomyelitis (PHO). Reactivity of serum IgG was tested with an array of recombinant proteins, representing over 2,652 in-vitro-translated open reading frames (ORFs) from a community-acquired methicillin-resistant S. aureus USA300 strain. High-level reactivity was demonstrated for 104 proteins with serum IgG in all patient samples. Overall, high-level IgG-reactivity was most commonly directed against a subset of secreted proteins. Although based on limited surveys, we found subsets of S. aureus proteins with differential reactivity with serum samples from patients with different clinical syndromes. Together, our studies have revealed a hierarchy within the diverse proteins of the S. aureus “immunome”, which will help to advance efforts to develop protective immunotherapeutic agents.
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28
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Dufresne J, Florentinus-Mefailoski A, Zhu PH, Bowden P, Marshall JG. Re-evaluation of the rabbit myosin protein standard used to create the empirical statistical model for decoy library searching. Anal Biochem 2018; 560:39-49. [PMID: 30171831 DOI: 10.1016/j.ab.2018.08.025] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2017] [Revised: 08/22/2018] [Accepted: 08/28/2018] [Indexed: 01/28/2023]
Abstract
A Rabbit myosin standard, like that used to create the empirical statistical model, was randomly and independently sampled by liquid chromatography micro electrospray ionization and tandem mass spectrometry (LC-ESI-MS/MS) with a linear quadrupole ion trap. The rabbit myosin protein standard appeared pure by SDS-PAGE and CBBR staining but showed many other proteins by silver staining. The LC-MS intensity from myosin and IgG samples were above the 99% safe limit of detection and quantification computed from 36 blank LC-ESI-MS/MS runs. The myosin contained ≤406 Gene Symbols, open reading frames or loci where 79 protein types showed ≥3 peptides from X!TANDEM. Myosins, actin, troponin, other proteins showed 95%-100% homology between the rabbit versus the human decoy library. The myosin protein complex from STRING was true positive compared to random or noise spectra MS/MS with a low type I error (p-value) and low FDR (q-value) computed in R. SDS-PAGE, Western blot, comparison to random and noise MS/MS spectra, X!TANDEM p-values, FDR corrected q-values, and STRING all agreed that the error rate of LC-ESI-MS/MS with a quadrupole ion trap is far below that assumed a priori by the design of the empirical statistical model for decoy library searching.
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Affiliation(s)
- Jaimie Dufresne
- Ryerson Analytical Biochemistry Laboratory (RABL), Kerr Hall East Rm 332b, Department of Chemistry and Biology, Faculty of Science, Ryerson University, Canada
| | - Angelique Florentinus-Mefailoski
- Ryerson Analytical Biochemistry Laboratory (RABL), Kerr Hall East Rm 332b, Department of Chemistry and Biology, Faculty of Science, Ryerson University, Canada
| | - Pei-Hong Zhu
- Ryerson Analytical Biochemistry Laboratory (RABL), Kerr Hall East Rm 332b, Department of Chemistry and Biology, Faculty of Science, Ryerson University, Canada
| | - Peter Bowden
- Ryerson Analytical Biochemistry Laboratory (RABL), Kerr Hall East Rm 332b, Department of Chemistry and Biology, Faculty of Science, Ryerson University, Canada
| | - John G Marshall
- Ryerson Analytical Biochemistry Laboratory (RABL), Kerr Hall East Rm 332b, Department of Chemistry and Biology, Faculty of Science, Ryerson University, Canada.
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29
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McClure JAM, Lakhundi S, Kashif A, Conly JM, Zhang K. Genomic Comparison of Highly Virulent, Moderately Virulent, and Avirulent Strains From a Genetically Closely-Related MRSA ST239 Sub-lineage Provides Insights Into Pathogenesis. Front Microbiol 2018; 9:1531. [PMID: 30042755 PMCID: PMC6048232 DOI: 10.3389/fmicb.2018.01531] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Accepted: 06/20/2018] [Indexed: 12/19/2022] Open
Abstract
The genomic comparison of virulent (TW20), moderately virulent (CMRSA6/CMRSA3), and avirulent (M92) strains from a genetically closely-related MRSA ST239 sub-lineage revealed striking similarities in their genomes and antibiotic resistance profiles, despite differences in virulence and pathogenicity. The main differences were in the spa gene (coding for staphylococcal protein A), lpl genes (coding for lipoprotein-like membrane proteins), cta genes (genes involved in heme synthesis), and the dfrG gene (coding for a trimethoprim-resistant dihydrofolate reductase), as well as variations in the presence or content of some prophages and plasmids, which could explain the virulence differences of these strains. TW20 was positive for all genetic traits tested, compared to CMRSA6, CMRSA3, and M92. The major components differing among these strains included spa and lpl with TW20 carrying both whereas CMRSA6/CMRSA3 carry spa identical to TW20 but have a disrupted lpl. M92 is devoid of both these traits. Considering the role played by these components in innate immunity and virulence, it is predicted that since TW20 has both the components intact and functional, these traits contribute to its pathogenesis. However, CMRSA6/CMRSA3 are missing one of these components, hence their intermediately virulent nature. On the contrary, M92 is completely devoid of both the spa and lpl genes and is avirulent. Mobile genetic elements play a potential role in virulence. TW20 carries three prophages (ϕSa6, ϕSa3, and ϕSPβ-like), a pathogenicity island and two plasmids. CMRSA6, CMRSA3, and M92 contain variations in one or more of these components. The virulence associated genes in these components include staphylokinase, entertoxins, antibiotic/antiseptic/heavy metal resistance and bacterial persistence. Additionally, there are many hypothetical proteins (present with variations among strains) with unknown function in these mobile elements which could be making an important contribution in the virulence of these strains. The above mentioned repertoire of virulence components in TW20 likely contributes to its increased virulence, while the absence and/or modification of one or more of these components in CMRSA6/CMRSA3 and M92 likely affects the virulence of the strains.
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Affiliation(s)
- Jo-Ann M. McClure
- Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, AB, Canada
| | - Sahreena Lakhundi
- Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, AB, Canada
- Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, AB, Canada
| | - Ayesha Kashif
- Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, AB, Canada
| | - John M. Conly
- Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, AB, Canada
- Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, AB, Canada
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB, Canada
- Department of Medicine, University of Calgary, Calgary, AB, Canada
- The Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
| | - Kunyan Zhang
- Centre for Antimicrobial Resistance, Alberta Health Services/Calgary Laboratory Services/University of Calgary, Calgary, AB, Canada
- Department of Pathology and Laboratory Medicine, University of Calgary, Calgary, AB, Canada
- Department of Microbiology, Immunology and Infectious Diseases, University of Calgary, Calgary, AB, Canada
- Department of Medicine, University of Calgary, Calgary, AB, Canada
- The Calvin, Phoebe and Joan Snyder Institute for Chronic Diseases, University of Calgary, Calgary, AB, Canada
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30
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Chen YE, Fischbach MA, Belkaid Y. Skin microbiota-host interactions. Nature 2018; 553:427-436. [PMID: 29364286 DOI: 10.1038/nature25177] [Citation(s) in RCA: 390] [Impact Index Per Article: 65.0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/28/2017] [Indexed: 12/23/2022]
Abstract
The skin is a complex and dynamic ecosystem that is inhabited by bacteria, archaea, fungi and viruses. These microbes-collectively referred to as the skin microbiota-are fundamental to skin physiology and immunity. Interactions between skin microbes and the host can fall anywhere along the continuum between mutualism and pathogenicity. In this Review, we highlight how host-microbe interactions depend heavily on context, including the state of immune activation, host genetic predisposition, barrier status, microbe localization, and microbe-microbe interactions. We focus on how context shapes the complex dialogue between skin microbes and the host, and the consequences of this dialogue for health and disease.
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Affiliation(s)
- Y Erin Chen
- Department of Dermatology, University of California San Francisco, San Francisco, California, USA.,Department of Bioengineering and ChEM-H, Stanford University, Stanford, California, USA
| | - Michael A Fischbach
- Department of Bioengineering and ChEM-H, Stanford University, Stanford, California, USA
| | - Yasmine Belkaid
- NIAID Microbiome Program, National Institute of Allergy and Infectious Disease, NIH, Bethesda, Maryland, USA.,Mucosal Immunology Section, Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Disease, NIH, Bethesda, Maryland, USA
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31
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Akam EA, Utterback RD, Marcero JR, Dailey HA, Tomat E. Disulfide-masked iron prochelators: Effects on cell death, proliferation, and hemoglobin production. J Inorg Biochem 2018; 180:186-193. [PMID: 29324291 PMCID: PMC5956897 DOI: 10.1016/j.jinorgbio.2017.12.016] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2017] [Revised: 12/20/2017] [Accepted: 12/24/2017] [Indexed: 10/18/2022]
Abstract
The iron metabolism of malignant cells, which is altered to ensure higher acquisition and utilization, motivates the investigation of iron chelation strategies in cancer treatment. In a prochelation approach aimed at increasing intracellular specificity, disulfide reduction/activation switches are incorporated on iron-binding scaffolds resulting in intracellularly activated scavengers. Herein, this strategy is applied to several tridentate donor sets including thiosemicarbazones, aroylhydrazones and semicarbazones. The novel prochelator systems are antiproliferative in breast adenocarcinoma cell lines (MCF-7 and metastatic MDA-MB-231) and do not result in the intracellular generation of oxidative stress. Consistent with iron deprivation, the tested prochelators lead to cell-cycle arrest at the G1/S interface and induction of apoptosis. Notably, although hemoglobin-synthesizing blood cells have the highest iron need in the human body, no significant impact on hemoglobin production was observed in the MEL (murine erythroleukemia) model of differentiating erythroid cells. This study provides new information on the intracellular effects of disulfide-based prochelators and indicates aroylhydrazone (AH1-S)2 as a promising prototype of a new class of antiproliferative prochelator systems.
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Affiliation(s)
- E A Akam
- Department of Chemistry and Biochemistry, The University of Arizona, United States
| | - R D Utterback
- Department of Chemistry and Biochemistry, The University of Arizona, United States
| | - J R Marcero
- Department of Microbiology and Department of Biochemistry and Molecular Biology, University of Georgia, United States
| | - H A Dailey
- Department of Microbiology and Department of Biochemistry and Molecular Biology, University of Georgia, United States
| | - E Tomat
- Department of Chemistry and Biochemistry, The University of Arizona, United States.
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32
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Kurppa K, Reuter LJ, Ritala A, Linder MB, Joensuu JJ. In-solution antibody harvesting with a plant-produced hydrophobin-Protein A fusion. PLANT BIOTECHNOLOGY JOURNAL 2018; 16:404-414. [PMID: 28640955 PMCID: PMC5787837 DOI: 10.1111/pbi.12780] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Revised: 06/01/2016] [Accepted: 06/16/2017] [Indexed: 05/02/2023]
Abstract
Purification is a bottleneck and a major cost factor in the production of antibodies. We set out to engineer a bifunctional fusion protein from two building blocks, Protein A and a hydrophobin, aiming at low-cost and scalable antibody capturing in solutions. Immunoglobulin-binding Protein A is widely used in affinity-based purification. The hydrophobin fusion tag, on the other hand, has been shown to enable purification by two-phase separation. Protein A was fused to two different hydrophobin tags, HFBI or II, and expressed transiently in Nicotiana benthamiana. The hydrophobins enhanced accumulation up to 35-fold, yielding up to 25% of total soluble protein. Both fused and nonfused Protein A accumulated in protein bodies. Hence, the increased yield could not be attributed to HFB-induced protein body formation. We also demonstrated production of HFBI-Protein A fusion protein in tobacco BY-2 suspension cells in 30 l scale, with a yield of 35 mg/l. Efficient partitioning to the surfactant phase confirmed that the fusion proteins retained the amphipathic properties of the hydrophobin block. The reversible antibody-binding capacity of the Protein A block was similar to the nonfused Protein A. The best-performing fusion protein was tested in capturing antibodies from hybridoma culture supernatant with two-phase separation. The fusion protein was able to carry target antibodies to the surfactant phase and subsequently release them back to the aqueous phase after a change in pH. This report demonstrates the potential of hydrophobin fusion proteins for novel applications, such as harvesting antibodies in solutions.
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Affiliation(s)
- Katri Kurppa
- VTT Technical Research Centre of Finland Ltd.EspooFinland
| | | | - Anneli Ritala
- VTT Technical Research Centre of Finland Ltd.EspooFinland
| | - Markus B. Linder
- VTT Technical Research Centre of Finland Ltd.EspooFinland
- Aalto UniversityDepartment of Biotechnology and Chemical TechnologyEspooFinland
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33
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Bakhmachuk A, Gorbatiuk O, Rachkov A, Dons'koi B, Khristosenko R, Ushenin I, Peshkova V, Soldatkin A. Surface Plasmon Resonance Investigations of Bioselective Element Based on the Recombinant Protein A for Immunoglobulin Detection. NANOSCALE RESEARCH LETTERS 2017; 12:112. [PMID: 28209032 PMCID: PMC5307396 DOI: 10.1186/s11671-017-1903-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 02/06/2017] [Indexed: 06/06/2023]
Abstract
The developed surface plasmon resonance (SPR) biosensor based on the recombinant Staphylococcal protein A with an additional cysteine residue (SPA-Cys) used as a biorecognition component showed a good selectivity and sensitivity for the immunoglobulin detection. The developed biosensor with SPA-Cys-based bioselective element can also be used as a first step of immunosensor creation. The successful immobilization of SPA-Cys on the nanolayer gold sensor surface of the SPR spectrometer was performed. The efficiency of blocking nonspecific sorption sites on the sensor surface with milk proteins, gelatin, BSA, and HSA was studied, and a rather high efficiency of using gelatin was confirmed. The SPR biosensor selectively interacted with IgG and did not interact with the control proteins. The linear dependence of the sensor response on the IgG concentration in the range from 2 to 10 μg/ml was shown. Using the calibration curve, the IgG concentration was measured in the model samples. The determined concentrations are in good agreement (r 2 = 0.97) with the given concentration of IgG.
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Affiliation(s)
- A Bakhmachuk
- Institute of Molecular Biology and Genetics of National Academy of Sciences of Ukraine, 150 Zabolotnogo Str., 03680, Kyiv, Ukraine.
- Institute of High Technologies, Taras Shevchenko National University of Kyiv, 2, korp.5, Pr. Akademika Hlushkova, Kyiv, 03022, Ukraine.
| | - O Gorbatiuk
- Institute of Molecular Biology and Genetics of National Academy of Sciences of Ukraine, 150 Zabolotnogo Str., 03680, Kyiv, Ukraine
- State Institute of Genetic and Regenerative Medicine, NAMS of Ukraine, 57/3, Velyka Vasyl'kivska Str., Kyiv, 03150, Ukraine
| | - A Rachkov
- Institute of Molecular Biology and Genetics of National Academy of Sciences of Ukraine, 150 Zabolotnogo Str., 03680, Kyiv, Ukraine
| | - B Dons'koi
- Institute of Pediatrics, Obstetrics and Gynecology, NAMS of Ukraine, 8, Maiborody Str., Kyiv, 04050, Ukraine
| | - R Khristosenko
- V.E. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, Prospect Nauki, Kyiv, 03028, Ukraine
| | - I Ushenin
- V.E. Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41, Prospect Nauki, Kyiv, 03028, Ukraine
| | - V Peshkova
- Institute of Molecular Biology and Genetics of National Academy of Sciences of Ukraine, 150 Zabolotnogo Str., 03680, Kyiv, Ukraine
- Institute of High Technologies, Taras Shevchenko National University of Kyiv, 2, korp.5, Pr. Akademika Hlushkova, Kyiv, 03022, Ukraine
| | - A Soldatkin
- Institute of Molecular Biology and Genetics of National Academy of Sciences of Ukraine, 150 Zabolotnogo Str., 03680, Kyiv, Ukraine
- Institute of High Technologies, Taras Shevchenko National University of Kyiv, 2, korp.5, Pr. Akademika Hlushkova, Kyiv, 03022, Ukraine
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34
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Zwolak A, Leettola CN, Tam SH, Goulet DR, Derebe MG, Pardinas JR, Zheng S, Decker R, Emmell E, Chiu ML. Rapid Purification of Human Bispecific Antibodies via Selective Modulation of Protein A Binding. Sci Rep 2017; 7:15521. [PMID: 29138497 PMCID: PMC5686111 DOI: 10.1038/s41598-017-15748-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Accepted: 10/30/2017] [Indexed: 02/04/2023] Open
Abstract
Methods to rapidly generate high quality bispecific antibodies (BsAb) having normal half-lives are critical for therapeutic programs. Here, we identify 3 mutations (T307P, L309Q, and Q311R or “TLQ”) in the Fc region of human IgG1 which disrupt interaction with protein A while enhancing interaction with FcRn. The mutations are shown to incrementally alter the pH at which a mAb elutes from protein A affinity resin. A BsAb comprised of a TLQ mutant and a wild-type IgG1 can be efficiently separated from contaminating parental mAbs by differential protein A elution starting from either a) purified parental mAbs, b) in-supernatant crossed parental mAbs, or c) co-transfected mAbs. We show that the Q311R mutation confers enhanced FcRn interaction in vitro, and Abs harboring either the Q311R or TLQ mutations have serum half-lives as long as wild-type human IgG1. The mutant Abs have normal thermal stability and Fcγ receptor interactions. Together, the results lead to a method for high-throughput generation of BsAbs suitable for in vivo studies.
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Affiliation(s)
- Adam Zwolak
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Catherine N Leettola
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Susan H Tam
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Dennis R Goulet
- Department of Medicinal Chemistry, University of Washington, Seattle, WA, 98195, USA
| | - Mehabaw G Derebe
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Jose R Pardinas
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Songmao Zheng
- Biologics Development Sciences, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Rose Decker
- Biologics Toxicology, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Eva Emmell
- Biologics Toxicology, Janssen Research & Development, LLC, Spring House, PA, 19477, USA
| | - Mark L Chiu
- Biologics Discovery, Janssen Research & Development, LLC, Spring House, PA, 19477, USA.
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35
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Liu D, Li Z, Wang G, Li T, Zhang L, Tang P. Virulence analysis of Staphylococcus aureus in a rabbit model of infected full-thickness wound under negative pressure wound therapy. Antonie Van Leeuwenhoek 2017; 111:161-170. [PMID: 28894985 PMCID: PMC5772129 DOI: 10.1007/s10482-017-0938-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/05/2017] [Indexed: 11/25/2022]
Abstract
The aim of this study was to evaluate the virulence of Staphylococcus aureus in a controlled animal study using the standard sterile gauze and negative pressure wound therapy (NPWT), including activation of agr, gene expression and production of virulence foctors and depth of bacterial invasion. The tissue specimens were harvested on days 0 (6 h after bacterial inoculation), 2, 4, 6, and 8 at the center of wound beds. Laser scanning confocal microscopy was performed to obtain bioluminescent images which were used to measure the depth of bacterial invasion. The agrA expression of S.aureus and the transcription and production of virulence factors including Eap, Spa and α-toxin were significantly different. The bacterial invasion depth was significantly less with effect of NPWT. The markedly different activation of quorum sensing systems that enable cell-to-cell communication and regulation of numerous colonization and virulence factors result in distinct gene expression and pathogenicity over time in different microenvironment. Thus, the agr system represents a fundamental regulatory paradigm that can encompass different adaptive strategies and accommodate horizontally acquired virulence determinants.
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Affiliation(s)
- Daohong Liu
- Department of Orthopedics, The 309th Hospital of PLA, Beijing, 100091, China
| | - Zhirui Li
- Department of Orthopedics, The General Hospital of People's Liberation Army, Beijing, 100853, China.,Department of Orthopedics, Chinese PLA General Hospital and Hainan Branch, Sanya, 572013, China
| | - Guoqi Wang
- Department of Orthopedics, The General Hospital of People's Liberation Army, Beijing, 100853, China
| | - Tongtong Li
- Department of Orthopedics, Tianjin Hospital, Tianjin, 300211, China
| | - Lihai Zhang
- Department of Orthopedics, The General Hospital of People's Liberation Army, Beijing, 100853, China
| | - Peifu Tang
- Department of Orthopedics, The General Hospital of People's Liberation Army, Beijing, 100853, China.
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36
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Xu B, Zhang P, Li W, Liu R, Tang J, Fan H. hsdS, Belonging to the Type I Restriction-Modification System, Contributes to the Streptococcus suis Serotype 2 Survival Ability in Phagocytes. Front Microbiol 2017; 8:1524. [PMID: 28848531 PMCID: PMC5552720 DOI: 10.3389/fmicb.2017.01524] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Accepted: 07/28/2017] [Indexed: 12/19/2022] Open
Abstract
Streptococcus suis serotype 2 (SS2) is an important zoonotic agent in swine and humans. Anti-phagocytosis and survival in phagocytic cells and whole blood is essential for bacteria to be pathogenic. In this study, the host specificity determinant specificity subunit (coded by hsdS) of the Type I Restriction-Modification system and two peptidoglycan-binding proteins (coded by lysM and lysM′, respectively), which were simultaneously found to be subjected to transcript-level influence by hsdS, were identified to facilitate the anti-phagocytosis of SS2 to a microglia cell line BV2. Furthermore, they significantly enhanced its survival in BV2, whole blood, and a peroxidation environment (H2O2) (p < 0.05), yet not in the acidic condition based on statistical analysis of the characteristic differences between gene mutants and wild-type SS2. In contrast, another specificity subunit, coded by hsdS′, that belonged to the same Type I Restriction-Modification system, only significantly reduced the survival ability of SS2 in the acidic condition when in the form of a gene-deleted mutant (p < 0.05), but it did not significantly influence the survival ability in other conditions mentioned above or have enhanced anti-phagocytosis action when compared with wild-type SS2. In addition, the mutation of hsdS significantly enhanced the secretion of nitric oxide and TNF-α by BV2 with SS2 incubation (p < 0.05). The SS2 was tested, and it failed to stimulate BV2 to produce IFN-γ. These results demonstrated that hsdS contributed to bacterial anti-phagocytosis and survival in adverse host environments through positively impacting the transcription of two peptidoglycan-binding protein genes, enhancing resistance to reactive oxygen species, and reducing the secretion of TNF-α and nitric oxide by phagocytes. These findings revealed new mechanisms of SS2 pathogenesis.
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Affiliation(s)
- Bin Xu
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China
| | - Ping Zhang
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China.,Poultry Institute, Chinese Academy of Agricultural SciencesYangzhou, China
| | - Weiyi Li
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China
| | - Rui Liu
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China
| | - Jinsheng Tang
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China
| | - Hongjie Fan
- College of Veterinary Medicine, Nanjing Agricultural UniversityNanjing, China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and ZoonosesYangzhou, China
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37
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Cavallari M. Rapid and Direct VHH and Target Identification by Staphylococcal Surface Display Libraries. Int J Mol Sci 2017; 18:ijms18071507. [PMID: 28704956 PMCID: PMC5535997 DOI: 10.3390/ijms18071507] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Revised: 07/07/2017] [Accepted: 07/10/2017] [Indexed: 01/01/2023] Open
Abstract
Unbiased and simultaneous identification of a specific antibody and its target antigen has been difficult without prior knowledge of at least one interaction partner. Immunization with complex mixtures of antigens such as whole organisms and tissue extracts including tumoral ones evokes a highly diverse immune response. During such a response, antibodies are generated against a variety of epitopes in the mixture. Here, we propose a surface display design that is suited to simultaneously identify camelid single domain antibodies and their targets. Immune libraries of single-domain antigen recognition fragments from camelid heavy chain-only antibodies (VHH) were attached to the peptidoglycan of Gram-positive Staphylococcus aureus employing its endogenous housekeeping sortase enzyme. The sortase transpeptidation reaction covalently attached the VHH to the bacterial peptidoglycan. The reversible nature of the reaction allowed the recovery of the VHH from the bacterial surface and the use of the VHH in downstream applications. These staphylococcal surface display libraries were used to rapidly identify VHH as well as their targets by immunoprecipitation (IP). Our novel bacterial surface display platform was stable under harsh screening conditions, allowed fast target identification, and readily permitted the recovery of the displayed VHH for downstream analysis.
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Affiliation(s)
- Marco Cavallari
- BIOSS Centre for Biological Signalling Studies, University of Freiburg, Schaenzlestrasse 18, 79104 Freiburg, Germany.
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38
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Yu X, Yang YP, Dikici E, Deo SK, Daunert S. Beyond Antibodies as Binding Partners: The Role of Antibody Mimetics in Bioanalysis. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2017; 10:293-320. [PMID: 28375702 PMCID: PMC5895458 DOI: 10.1146/annurev-anchem-061516-045205] [Citation(s) in RCA: 69] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
The emergence of novel binding proteins or antibody mimetics capable of binding to ligand analytes in a manner analogous to that of the antigen-antibody interaction has spurred increased interest in the biotechnology and bioanalytical communities. The goal is to produce antibody mimetics designed to outperform antibodies with regard to binding affinities, cellular and tumor penetration, large-scale production, and temperature and pH stability. The generation of antibody mimetics with tailored characteristics involves the identification of a naturally occurring protein scaffold as a template that binds to a desired ligand. This scaffold is then engineered to create a superior binder by first creating a library that is then subjected to a series of selection steps. Antibody mimetics have been successfully used in the development of binding assays for the detection of analytes in biological samples, as well as in separation methods, cancer therapy, targeted drug delivery, and in vivo imaging. This review describes recent advances in the field of antibody mimetics and their applications in bioanalytical chemistry, specifically in diagnostics and other analytical methods.
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Affiliation(s)
- Xiaowen Yu
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Yu-Ping Yang
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Emre Dikici
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Sapna K Deo
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
| | - Sylvia Daunert
- Department of Biochemistry and Molecular Biology, Miller School of Medicine, University of Miami, Miami, Florida 33136;
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Wang Y, Ballou B, Schmidt BF, Andreko S, St Croix CM, Watkins SC, Bruchez MP. Affibody-targeted fluorogen activating protein for in vivo tumor imaging. Chem Commun (Camb) 2017; 53:2001-2004. [PMID: 28120951 PMCID: PMC5340305 DOI: 10.1039/c6cc09137g] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Molecular imaging using near-infrared (NIR) fluorescence is useful for intraoperative imaging and real-time margin identification. Directly conjugated IR dyes possess useful properties for in vivo imaging, but conjugation often substantially alters the circulation dynamics of targeting moieties. We developed and characterized a new tumor-targeting probe, affiFAP, which consists of a protein that specifically binds EGFR (affibody) and a fluorogen activating protein (FAP). This compact molecular recognition reagent can reversibly bind and activate fluorescence of otherwise nonfluorescent dyes and allows tumor visualization with low nonspecific tissue staining. We demonstrate molecular pre-targeting of affiFAPs and subsequent systemic or topical application of fluorogenic dye to achieve high contrast, fast clearance, and good tissue penetration that may be used in clinical settings to molecularly define tumor margins.
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Affiliation(s)
- Yi Wang
- The Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA. and The Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Byron Ballou
- The Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Brigitte F Schmidt
- The Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Sue Andreko
- The Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213, USA
| | - Claudette M St Croix
- Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Simon C Watkins
- Center for Biologic Imaging, University of Pittsburgh, Pittsburgh, PA 15261, USA
| | - Marcel P Bruchez
- The Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA 15213, USA. and The Molecular Biosensor and Imaging Center, Carnegie Mellon University, Pittsburgh, PA 15213, USA and The Department of Chemistry, Carnegie Mellon University, Pittsburgh, PA 15213, USA
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Leenheer D, ten Dijke P, Hipolito CJ. A current perspective on applications of macrocyclic-peptide-based high-affinity ligands. Biopolymers 2016; 106:889-900. [PMID: 27352774 PMCID: PMC5132055 DOI: 10.1002/bip.22900] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 05/24/2016] [Accepted: 05/31/2016] [Indexed: 01/05/2023]
Abstract
Monoclonal antibodies can bind with high affinity and high selectivity to their targets. As a tool in therapeutics or diagnostics, however, their large size (∼150 kDa) reduces penetration into tissue and prevents passive cellular uptake. To overcome these and other problems, minimized protein scaffolds have been chosen or engineered, with care taken to not compromise binding affinity or specificity. An alternate approach is to begin with a minimal non-antibody scaffold and select functional ligands from a de novo library. We will discuss the structure, production, applications, strengths, and weaknesses of several classes of antibody-derived ligands, that is, antibodies, intrabodies, and nanobodies, and nonantibody-derived ligands, that is, monobodies, affibodies, and macrocyclic peptides. In particular, this review is focussed on macrocyclic peptides produced by the Random non-standard Peptides Integrated Discovery (RaPID) system that are small in size (typically ∼2 kDa), but are able to perform tasks typically handled by larger proteinaceous ligands.
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Affiliation(s)
- Daniël Leenheer
- Ph.D. Program in Human Biology, School of Integrative and Global MajorsUniversity of TsukubaTsukubaIbarakiJapan
| | - Peter ten Dijke
- Leiden University Medical Center, Department of Molecular Cell BiologyLeidenSouth HollandThe Netherlands
- Cancer Signaling, Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of TsukubaTsukubaIbarakiJapan
| | - Christopher John Hipolito
- Cancer Signaling, Graduate School of Comprehensive Human Sciences and Faculty of Medicine, University of TsukubaTsukubaIbarakiJapan
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Development of an immunoFET biosensor for the detection of biotinylated PCR product. Heliyon 2016; 2:e00188. [PMID: 27822563 PMCID: PMC5090196 DOI: 10.1016/j.heliyon.2016.e00188] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 09/01/2016] [Accepted: 10/21/2016] [Indexed: 12/19/2022] Open
Abstract
ImmunoFET (IMFET) biosensor is a simple platform for the detection of biotinylated products of polymerase chain reaction (PCR). Construction of the IMFET biosensor started with adsorption of 1.5 mg/mL of protein A (PA) onto the insulated gate surface of ISFET for 90 min. Next, the immobilized 1/500 dilution of anti-biotin antibody was adsorbed onto the PA layer for 60 min. The IMFET biosensor was subsequently ready for detection of the biotinylated amplicon. The IMFET biosensor showed highly specific binding to the biotinylated PCR product of the phaE gene of Haloquadratum walsbyi DSM 16854. The phaE gene is a biomarker of polyhydroxyalkanoate (PHA) producers that contain PHA synthase class III. The lowest amount of DNA template of H. walsbyi DSM 16854 that the IMFET biosensor could detect was 125 fg. The IMFET biosensor has a lower amount of detection compared with a DNA lateral flow biosensor from our previous study. The degree of linearity of the biosensor signal was influenced by the concentration of the biotinylated amplicon. The IMFET biosensor also has a short response time (approximately 30 times) to detect the phaE amplicon compared to an agarose gel electrophoresis. The IMFET biosensor is a promising tool for the detection of the biotinylated PCR product, and it can be integrated into a micro total analysis system (μTAS).
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Malm M, Frejd FY, Ståhl S, Löfblom J. Targeting HER3 using mono- and bispecific antibodies or alternative scaffolds. MAbs 2016; 8:1195-1209. [PMID: 27532938 PMCID: PMC5058629 DOI: 10.1080/19420862.2016.1212147] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The human epidermal growth factor receptor 3 (HER3) has in recent years been recognized as a key node in the complex signaling network of many different cancers. It is implicated in de novo and acquired resistance against therapies targeting other growth factor receptors, e.g., EGFR, HER2, and it is a major activator of the PI3K/Akt signaling pathway. Consequently, HER3 has attracted substantial attention, and is today a key target for drugs in clinical development. Sophisticated protein engineering approaches have enabled the generation of a range of different affinity proteins targeting this receptor, including antibodies and alternative scaffolds that are either mono- or bispecific. Here, we describe HER3 and its role as a key tumor target, and give a comprehensive review of HER3-targeted proteins currently in development, including discussions on the opportunities and challenges of targeting this receptor.
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Affiliation(s)
- Magdalena Malm
- a Division of Protein Technology, School of Biotechnology, KTH-Royal Institute of Technology, SE , Stockholm
| | - Fredrik Y Frejd
- b Affibody AB, SE, Stockholm , Sweden.,c Department of Immunology , Genetics and Pathology, Uppsala University , Uppsala , Sweden
| | - Stefan Ståhl
- a Division of Protein Technology, School of Biotechnology, KTH-Royal Institute of Technology, SE , Stockholm
| | - John Löfblom
- a Division of Protein Technology, School of Biotechnology, KTH-Royal Institute of Technology, SE , Stockholm
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Peptidoglycan-linked protein A promotes T cell-dependent antibody expansion during Staphylococcus aureus infection. Proc Natl Acad Sci U S A 2016; 113:5718-23. [PMID: 27140614 DOI: 10.1073/pnas.1524267113] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A hallmark of Staphylococcus aureus disease in humans is persistent infections without development of protective immune responses. Infected patients generate VH3 plasmablast expansions and increased VH3 idiotype Ig; however, the mechanisms for staphylococcal modification of immune responses are not known. We report here that S. aureus-infected mice generate VH3 antibody expansions via a mechanism requiring MHC-restricted antigen presentation to CD4(+) T cells and staphylococcal protein A (SpA), a cell wall-anchored surface molecule that binds Fcγ and VH3 variant heavy chains of Ig. VH3 expansion occurred with peptidoglycan-linked SpA from the bacterial envelope but not with recombinant SpA, and optimally required five tandem repeats of its Ig-binding domains. Signaling via receptor-interacting serine/threonine protein kinase 2 (RIPK2) was essential for implementing peptidoglycan-linked SpA superantigen activity. VH3 clan IgG from S. aureus-infected or SpA-treated animals was not pathogen-specific, suggesting that SpA cross-linking of VH3 idiotype B-cell receptors and activation via attached peptidoglycan are the determinants of staphylococcal escape from adaptive immune responses.
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Wu Z, Shao J, Ren H, Tang H, Zhou M, Dai J, Lai L, Yao H, Fan H, Chen D, Zong J, Lu C. A Streptococcus suis LysM domain surface protein contributes to bacterial virulence. Vet Microbiol 2016; 187:64-69. [PMID: 27066710 DOI: 10.1016/j.vetmic.2016.03.017] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/16/2016] [Accepted: 03/25/2016] [Indexed: 01/20/2023]
Abstract
Streptococcus suis (SS) is a major swine pathogen, as well as a zoonotic agent for humans. Numerous factors contribute to SS virulence, but the pathogenesis of SS infection is poorly understood. Here, we show that a novel SS surface protein containing a LysM at the N-terminus (SS9-LysM) contributes to SS virulence. Homology analysis revealed that the amino acid sequence of SS9-LysM from the SS strain GZ0565 shares 99.8-68.7% identity with homologous proteins from other SS strains and 41.2% identity with Group B Streptococcal protective antigen Sip. Immunization experiments showed that 7 out of 30 mice immunized with recombinant SS9-LysM were protected against challenge with the virulent GZ0565 strain, while all of the control mice died within 48h following bacterial challenge. In mouse infection model, the virulence of the SS9-LysM deletion mutant (ΔSS9-LysM) was reduced compared with the wild-type (WT) strain GZ0565 and SS9-LysM complemented strain. In addition, ΔSS9-LysM was significantly more sensitive to killing by pig blood ex vivo and mouse blood in vivo compared with the WT strain and SS9-LysM complemented strain. In vivo transcriptome analysis in mouse blood showed that the WT strain reduced the expression of host genes related to iron-binding by SS9-LysM. Moreover, the total free iron concentration in blood from infected mice was significantly lower for the ΔSS9-LysM strain compared with the WT strain. Together, our data reveal that SS9-LysM facilitates SS survival within blood by releasing more free iron from the host. This represents a new mechanism of SS pathogenesis.
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Affiliation(s)
- Zongfu Wu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
| | - Jing Shao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Haiyan Ren
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Huanyu Tang
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Mingyao Zhou
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Jiao Dai
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Liying Lai
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Huochun Yao
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China
| | - Hongjie Fan
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China; Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Dai Chen
- Novel Bioinformatics Co., Ltd., Shanghai, China
| | - Jie Zong
- Novel Bioinformatics Co., Ltd., Shanghai, China
| | - Chengping Lu
- College of Veterinary Medicine, Nanjing Agricultural University, Nanjing 210095, China; Key Lab of Animal Bacteriology, Ministry of Agriculture, Nanjing 210095, China; OIE Reference Lab for Swine Streptococcosis, Nanjing 210095, China.
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45
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Parker D, Ahn D, Cohen T, Prince A. Innate Immune Signaling Activated by MDR Bacteria in the Airway. Physiol Rev 2016; 96:19-53. [PMID: 26582515 DOI: 10.1152/physrev.00009.2015] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Health care-associated bacterial pneumonias due to multiple-drug resistant (MDR) pathogens are an important public health problem and are major causes of morbidity and mortality worldwide. In addition to antimicrobial resistance, these organisms have adapted to the milieu of the human airway and have acquired resistance to the innate immune clearance mechanisms that normally prevent pneumonia. Given the limited efficacy of antibiotics, bacterial clearance from the airway requires an effective immune response. Understanding how specific airway pathogens initiate and regulate innate immune signaling, and whether this response is excessive, leading to host-induced pathology may guide future immunomodulatory therapy. We will focus on three of the most important causes of health care-associated pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, and review the mechanisms through which an inappropriate or damaging innate immune response is stimulated, as well as describe how airway pathogens cause persistent infection by evading immune activation.
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Affiliation(s)
- Dane Parker
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Danielle Ahn
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Taylor Cohen
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
| | - Alice Prince
- Departments of Pediatrics and Pharmacology, Columbia University, New York, New York
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Sadaka A, Durand ML, Sisk R, Gilmore MS. Staphylococcus aureus and its Bearing on Ophthalmic Disease. Ocul Immunol Inflamm 2015; 25:111-121. [PMID: 26679534 DOI: 10.3109/09273948.2015.1075559] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
PURPOSE To review antibiotic resistance associated with S. aureus endophthalmitis and the virulence of S. aureus. METHODS Review of the current and prospective approaches for treating S. aureus endophthalmitis. RESULTS Bacterial endophthalmitis remains to be a major threat for vision. S. aureus endophthalmitis specifically, carries a poor visual prognosis making early diagnosis and treatment crucial. Methicillin resistant Staphylococcus aureus (MRSA) endophthalmitis represents a significant number of S. aureus endophthalmitis cases. MRSA with reduced susceptibility to glycopeptide antibiotics such as vancomycin (vancomycin intermediate S. aureus, VISA) have also emerged in the ocular infections, and there has been a rise in S. aureus resistance to new and old generation fluoroquinolones that are commonly used for prophylaxis after intravitreal injections and intraocular surgeries. CONCLUSIONS With the rise in the number of penetrating procedures in the ophthalmology practice and the parallel rise in antibiotic resistance, prophylaxis and awareness of the antimicrobial resistance profiles remain crucial and the identification of novel antimicrobials is essential.
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Affiliation(s)
- Ama Sadaka
- a Cincinnati Eye Institute, University of Cincinnati College of Medicine , Department of Ophthalmology , Cincinnati , Ohio , USA.,b Department of Ophthalmology , Massachusetts Eye and Ear Infirmary , Boston , Massachusetts , USA
| | - Marlene L Durand
- b Department of Ophthalmology , Massachusetts Eye and Ear Infirmary , Boston , Massachusetts , USA.,c Division of Infectious Diseases, Department of Medicine , Massachusetts General Hospital , Boston , Massachusetts , USA
| | - Robert Sisk
- a Cincinnati Eye Institute, University of Cincinnati College of Medicine , Department of Ophthalmology , Cincinnati , Ohio , USA
| | - Michael S Gilmore
- b Department of Ophthalmology , Massachusetts Eye and Ear Infirmary , Boston , Massachusetts , USA.,d Department of Ophthalmology , Harvard Medical School , Boston , Massachusetts , USA.,e Department of Microbiology and Molecular Genetics , Harvard Medical School , Boston , Massachusetts , USA
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Aguayo S, Donos N, Spratt D, Bozec L. Nanoadhesion of Staphylococcus aureus onto Titanium Implant Surfaces. J Dent Res 2015; 94:1078-84. [PMID: 26130256 DOI: 10.1177/0022034515591485] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Adhesion of bacteria to dental implant surfaces is the critical initial step in the process of biofilm colonization; however, the specific nanoadhesive interactions occurring during the first contact between bacterial cells and biomaterial substrates remain poorly understood. In this report, we utilize single-cell force spectroscopy to characterize the dynamics of the initial interaction between living Staphylococcus aureus cells and machined titanium surfaces at the nanoscale. Values for maximum adhesion force were found to increase from 0-s (-0.27 ± 0.30 nN) to 60-s (-9.15 ± 0.78 nN) surface delays, with similar results observed for total adhesion work (7.39 ± 2.38 and 988.06 ± 117.08 aJ, respectively). Single unbinding events observed at higher surface delays were modeled according to the wormlike chain model, obtaining molecular contour-length predictions of 314.06 ± 9.27 nm. Average single-bond rupture forces of -0.95 ± 0.04 nN were observed at increased contact times. Short- and long-range force components of bacterial adhesion were obtained by Poisson analysis of single unbinding event peaks, yielding values of -0.75 ± 0.04 and -0.58 ± 0.15 nN, respectively. Addition of 2-mg/mL chlorhexidine to the buffer solution resulted in the inhibition of specific adhesive events but an increased overall adhesion force and work. These results suggest that initial attachment of S. aureus to smooth titanium is mostly mediated by short-range attractive forces observed at higher surface delays.
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Affiliation(s)
- S Aguayo
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK
| | - N Donos
- Periodontology Unit, UCL Eastman Dental Institute, University College London, London, UK
| | - D Spratt
- Division of Microbial Diseases, UCL Eastman Dental Institute, University College London, London, UK
| | - L Bozec
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, University College London, London, UK
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Minai-Fleminger Y, Gangwar RS, Migalovich-Sheikhet H, Seaf M, Leibovici V, Hollander N, Feld M, Moses AE, Homey B, Levi-Schaffer F. The CD48 receptor mediates Staphylococcus aureus human and murine eosinophil activation. Clin Exp Allergy 2015; 44:1335-46. [PMID: 25255823 DOI: 10.1111/cea.12422] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 06/22/2014] [Accepted: 08/01/2014] [Indexed: 12/12/2022]
Abstract
BACKGROUND Allergy is characterized by eosinophilia and an increased susceptibility to microbial infection. Atopic dermatitis (AD) is typically associated with Staphylococcus aureus (SA) colonization. Some of the mechanisms by which SA and its exotoxins interact with eosinophils remain elusive. CD48, a glycosylphosphatidylinositol-anchored receptor belonging to the CD2 family, participates in mast cells-SA stimulating cross-talk, facilitates the formation of the mast cell/eosinophils effector unit and as expressed by eosinophils, mediates experimental asthma. OBJECTIVE To investigate the role of CD48 expressed on human peripheral blood and mouse bone marrow-derived eosinophils (BMEos) in their interaction with heat-killed SA and its three exotoxins, Staphylococcal enterotoxin B (SEB), protein A (PtA) and peptidoglycan (PGN). METHODS Eosinophils were obtained from human peripheral blood and BM of WT and CD48-/- mice. SA was heat killed and eosinophils-SA/exotoxins interactions were analyzed by confocal microscopy, adhesion and degranulation, cell viability, cytokine release and cell signalling. In addition, peritonitis was induced by SEB injection into CD48-/- and WT mice. CD48 expression was studied in AD patients' skin and as expressed on their leucocytes in the peripheral blood. RESULTS We provide evidence for the recognition and direct physical interaction between eosinophils and SA/exotoxins. Skin of AD patients showed a striking increase of eosinophil-associated CD48 expression while on peripheral blood leucocytes it was down-regulated. SA/exotoxins enhanced CD48 eosinophil expression, bound to CD48 and caused eosinophil activation and signal transduction. These effects were significantly decreased by blocking CD48 on human eosinophils or in BMEos from CD48-/- mice. We have also explored the role of CD48 in a SEB-induced peritonitis model in CD48-/- mice by evaluating inflammatory peritoneal cells, eosinophil numbers and activation. CONCLUSIONS These data demonstrate the important role of CD48 in SA/exotoxins-eosinophil activating interactions that can take place during allergic responses and indicate CD48 as a novel therapeutic target for allergy and especially of AD.
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Affiliation(s)
- Y Minai-Fleminger
- Pharmacology & Experimental Therapeutics, Institute for Drug Research, School of Pharmacy, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, Israel
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Weber J, Haberkorn U, Mier W. Cancer stratification by molecular imaging. Int J Mol Sci 2015; 16:4918-46. [PMID: 25749472 PMCID: PMC4394457 DOI: 10.3390/ijms16034918] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2014] [Revised: 02/13/2015] [Accepted: 02/17/2015] [Indexed: 12/29/2022] Open
Abstract
The lack of specificity of traditional cytotoxic drugs has triggered the development of anticancer agents that selectively address specific molecular targets. An intrinsic property of these specialized drugs is their limited applicability for specific patient subgroups. Consequently, the generation of information about tumor characteristics is the key to exploit the potential of these drugs. Currently, cancer stratification relies on three approaches: Gene expression analysis and cancer proteomics, immunohistochemistry and molecular imaging. In order to enable the precise localization of functionally expressed targets, molecular imaging combines highly selective biomarkers and intense signal sources. Thus, cancer stratification and localization are performed simultaneously. Many cancer types are characterized by altered receptor expression, such as somatostatin receptors, folate receptors or Her2 (human epidermal growth factor receptor 2). Similar correlations are also known for a multitude of transporters, such as glucose transporters, amino acid transporters or hNIS (human sodium iodide symporter), as well as cell specific proteins, such as the prostate specific membrane antigen, integrins, and CD20. This review provides a comprehensive description of the methods, targets and agents used in molecular imaging, to outline their application for cancer stratification. Emphasis is placed on radiotracers which are used to identify altered expression patterns of cancer associated markers.
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Affiliation(s)
- Justus Weber
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
| | - Uwe Haberkorn
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
| | - Walter Mier
- Heidelberg University Hospital, Department of Nuclear Medicine, Im Neuenheimer Feld 400, 69120 Heidelberg, Germany.
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50
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LaCava J, Molloy KR, Taylor MS, Domanski M, Chait BT, Rout MP. Affinity proteomics to study endogenous protein complexes: pointers, pitfalls, preferences and perspectives. Biotechniques 2015; 58:103-19. [PMID: 25757543 PMCID: PMC4465938 DOI: 10.2144/000114262] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2015] [Accepted: 02/17/2015] [Indexed: 01/13/2023] Open
Abstract
Dissecting and studying cellular systems requires the ability to specifically isolate distinct proteins along with the co-assembled constituents of their associated complexes. Affinity capture techniques leverage high affinity, high specificity reagents to target and capture proteins of interest along with specifically associated proteins from cell extracts. Affinity capture coupled to mass spectrometry (MS)-based proteomic analyses has enabled the isolation and characterization of a wide range of endogenous protein complexes. Here, we outline effective procedures for the affinity capture of protein complexes, highlighting best practices and common pitfalls.
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Affiliation(s)
- John LaCava
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York
- Institute for Systems Genetics, New York University School of Medicine, New York, NY
| | - Kelly R. Molloy
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY
| | - Martin S. Taylor
- High Throughput Biology Center and Department of Pharmacology and Molecular Sciences, Johns Hopkins University School of Medicine, Baltimore, MD
| | - Michal Domanski
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York
- Centre for mRNP Biogenesis and Metabolism, Department of Molecular Biology and Genetics, Aarhus University, Aarhus, Denmark
| | - Brian T. Chait
- Laboratory of Mass Spectrometry and Gaseous Ion Chemistry, The Rockefeller University, New York, NY
| | - Michael P. Rout
- Laboratory of Cellular and Structural Biology, The Rockefeller University, New York
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