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Chen L, Yuan L, Sun T, Liu R, Huang Q, Deng S. The performance of VCS(volume, conductivity, light scatter) parameters in distinguishing latent tuberculosis and active tuberculosis by using machine learning algorithm. BMC Infect Dis 2023; 23:881. [PMID: 38104064 PMCID: PMC10725592 DOI: 10.1186/s12879-023-08531-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2023] [Accepted: 08/11/2023] [Indexed: 12/19/2023] Open
Abstract
BACKGROUND Tuberculosis is a chronic infectious disease caused by mycobacterium tuberculosis (MTB) and is the ninth leading cause of death worldwide. It is still difficult to distinguish active TB from latent TB,but it is very important for individualized management and treatment to distinguish whether patients are active or latent tuberculosis infection. METHODS A total of 220 subjects, including active TB patients (ATB, n = 97) and latent TB patients (LTB, n = 113), were recruited in this study .46 features about blood routine indicators and the VCS parameters (volume, conductivity, light scatter) of neutrophils(NE), monocytes(MO), and lymphocytes(LY) were collected and was constructed classification model by four machine learning algorithms(logistic regression(LR), random forest(RF), support vector machine(SVM) and k-nearest neighbor(KNN)). And the area under the precision-recall curve (AUPRC) and the area under the receiver operating characteristic curve (AUROC) to estimate of the model's predictive performance for dentifying active and latent tuberculosis infection. RESULTS After verification,among the four classifications, LR and RF had the best performance (AUROC = 1, AUPRC = 1), followed by SVM (AUROC = 0.967, AUPRC = 0.971), KNN (AUROC = 0.943, AUPRC = 0.959) in the training set. And LR had the best performance (AUROC = 0.977, AUPRC = 0.957), followed by SVM (AUROC = 0.962, AUPRC = 0.949), RF (AUROC = 0.903, AUPRC = 0.922),KNN(AUROC = 0.883, AUPRC = 0.901) in the testing set. CONCLUSIONS The machine learning algorithm classifier based on leukocyte VCS parameters is of great value in identifying active and latent tuberculosis infection.
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Affiliation(s)
- Lijiao Chen
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, P.R. China
| | - Lingke Yuan
- Science in Computational Finance, Carnegie Mellon University, Pittsburgh, PA, USA
| | - Tingting Sun
- College of Medical Technology, Chongqing Medical and Pharmaceutical College, Chongqing, China
| | - Ruiqing Liu
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, P.R. China
| | - Qing Huang
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, P.R. China.
| | - Shaoli Deng
- Department of Laboratory Medicine, Daping Hospital, Army Medical University, Chongqing, 400042, P.R. China.
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2
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Shekhar S, Brar NK, Håkansson AP, Petersen FC. Treatment of Mouse Infants with Amoxicillin, but Not the Human Milk-Derived Antimicrobial HAMLET, Impairs Lung Th17 Responses. Antibiotics (Basel) 2023; 12:antibiotics12020423. [PMID: 36830333 PMCID: PMC9952748 DOI: 10.3390/antibiotics12020423] [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: 01/16/2023] [Revised: 02/14/2023] [Accepted: 02/18/2023] [Indexed: 02/23/2023] Open
Abstract
Emerging evidence suggests differential effects of therapeutic antibiotics on infant T cell responses to pathogens. In this study, we explored the impact of the treatment of mouse infants with amoxicillin and the human milk-derived antimicrobial HAMLET (human alpha-lactalbumin made lethal to tumor cells) on T cell responses to Streptococcus pneumoniae. Lung cells and splenocytes were isolated from the infant mice subjected to intranasal administration of amoxicillin, HAMLET, or a combination of HAMLET and amoxicillin, and cultured with S. pneumoniae to measure T cell responses. After in-vitro stimulation with S. pneumoniae, lung cells from amoxicillin- or amoxicillin plus HAMLET-treated mice produced lower levels of Th17 (IL-17A), but not Th1 (IFN-γ), cytokine than mice receiving HAMLET or PBS. IL-17A/IFN-γ cytokine levels produced by the stimulated splenocytes, on the other hand, revealed no significant difference among treatment groups. Further analysis of T cell cytokine profiles by flow cytometry showed that lung CD4+, but not CD8+, T cells from amoxicillin- or HAMLET plus amoxicillin-treated mice expressed decreased levels of IL-17A compared to those from HAMLET-exposed or control mice. Collectively, these results indicate that exposure of infant mice to amoxicillin, but not HAMLET, may suppress lung Th17 responses to S. pneumoniae.
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Affiliation(s)
| | | | - Anders P. Håkansson
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, 21428 Malmö, Sweden
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3
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Chiou JT, Shi YJ, Lee YC, Wang LJ, Chen YJ, Chang LS. Carboxyl group-modified α-lactalbumin induces TNF-α-mediated apoptosis in leukemia and breast cancer cells through the NOX4/p38 MAPK/PP2A axis. Int J Biol Macromol 2021; 187:513-527. [PMID: 34310992 DOI: 10.1016/j.ijbiomac.2021.07.133] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 07/19/2021] [Accepted: 07/20/2021] [Indexed: 12/30/2022]
Abstract
To clarify the mechanism of semicarbazide-modified α-lactalbumin (SEM-LA)-mediated cytotoxicity, we investigated its effect on human U937 leukemia cells and MCF-7 breast cancer cells in the current study. SEM-LA induced apoptosis in U937 cells, which showed increased NOX4 expression, procaspase-8 degradation, and t-Bid production. FADD depletion inhibited SEM-LA-elicited caspase-8 activation, t-Bid production, and cell death, indicating that SEM-LA activated death receptor-mediated apoptosis in U937 cells. SEM-LA stimulated Ca2+-mediated Akt activation, which in turn increased Sp1- and p300-mediated NOX4 transcription. The upregulation of NOX4 expression promoted ROS-mediated p38 MAPK phosphorylation, leading to protein phosphatase 2A (PP2A)-regulated tristetraprolin (TTP) degradation. Remarkably, TTP downregulation increased the stability of TNF-α mRNA, resulting in the upregulation of TNF-α protein expression. Abolishment of Ca2+-NOX4-ROS axis-mediated p38 MAPK activation attenuated SEM-LA-induced TNF-α upregulation and protected U937 cells from SEM-LA-mediated cytotoxicity. The restoration of TTP expression alleviated the effect of TNF-α upregulation and cell death induced by SEM-LA. Altogether, the data in this study demonstrate that SEM-LA activates TNF-α-mediated apoptosis in U937 cells through the NOX4/p38 MAPK/PP2A axis. We think that a similar pathway can also explain the death of MCF-7 human breast cancer cells after SEM-LA treatment.
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Affiliation(s)
- Jing-Ting Chiou
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Yi-Jun Shi
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Yuan-Chin Lee
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Liang-Jun Wang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan
| | - Ying-Jung Chen
- Department of Fragrance and Cosmetic Science, Kaohsiung Medical University, Kaohsiung 807, Taiwan
| | - Long-Sen Chang
- Institute of Biomedical Sciences, National Sun Yat-Sen University, Kaohsiung 804, Taiwan; Department of Biotechnology, Kaohsiung Medical University, Kaohsiung 807, Taiwan.
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4
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Simmons JD, Van PT, Stein CM, Chihota V, Ntshiqa T, Maenetje P, Peterson GJ, Reynolds A, Benchek P, Velen K, Fielding KL, Grant AD, Graustein AD, Nguyen FK, Seshadri C, Gottardo R, Mayanja-Kizza H, Wallis RS, Churchyard G, Boom WH, Hawn TR. Monocyte metabolic transcriptional programs associate with resistance to tuberculin skin test/interferon-γ release assay conversion. J Clin Invest 2021; 131:e140073. [PMID: 34111032 DOI: 10.1172/jci140073] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Accepted: 06/03/2021] [Indexed: 12/14/2022] Open
Abstract
After extensive exposure to Mycobacterium tuberculosis (Mtb), most individuals acquire latent Mtb infection (LTBI) defined by a positive tuberculin skin test (TST) or interferon-γ release assay (IGRA). To identify mechanisms of resistance to Mtb infection, we compared transcriptional profiles from highly exposed contacts who resist TST/IGRA conversion (resisters, RSTRs) and controls with LTBI using RNAseq. Gene sets related to carbon metabolism and free fatty acid (FFA) transcriptional responses enriched across 2 independent cohorts suggesting RSTR and LTBI monocytes have distinct activation states. We compared intracellular Mtb replication in macrophages treated with FFAs and found that palmitic acid (PA), but not oleic acid (OA), enhanced Mtb intracellular growth. This PA activity correlated with its inhibition of proinflammatory cytokines in Mtb-infected cells. Mtb growth restriction in PA-treated macrophages was restored by activation of AMP kinase (AMPK), a central host metabolic regulator known to be inhibited by PA. Finally, we genotyped AMPK variants and found 7 SNPs in PRKAG2, which encodes the AMPK-γ subunit, that strongly associated with RSTR status. Taken together, RSTR and LTBI phenotypes are distinguished by FFA transcriptional programs and by genetic variation in a central metabolic regulator, which suggests immunometabolic pathways regulate TST/IGRA conversion.
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Affiliation(s)
- Jason D Simmons
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Phu T Van
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | - Catherine M Stein
- Department of Population & Quantitative Health Sciences and.,Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Violet Chihota
- School of Public Health, University of Witwatersrand, Johannesburg, South Africa.,The Aurum Institute, Parktown, South Africa
| | | | | | - Glenna J Peterson
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Anthony Reynolds
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | | | | | - Katherine L Fielding
- School of Public Health, University of Witwatersrand, Johannesburg, South Africa.,TB Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Alison D Grant
- School of Public Health, University of Witwatersrand, Johannesburg, South Africa.,TB Centre, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Africa Health Research Institute, School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa
| | - Andrew D Graustein
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Felicia K Nguyen
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Chetan Seshadri
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
| | - Raphael Gottardo
- Fred Hutchinson Cancer Research Center, Seattle, Washington, USA
| | | | | | | | - W Henry Boom
- Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA
| | - Thomas R Hawn
- TB Research and Training Center, Department of Medicine, University of Washington, Seattle, Washington, USA
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5
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Morrin ST, Buck RH, Farrow M, Hickey RM. Milk-derived anti-infectives and their potential to combat bacterial and viral infection. J Funct Foods 2021. [DOI: 10.1016/j.jff.2021.104442] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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6
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Vansarla G, Håkansson AP, Bergenfelz C. HAMLET a human milk protein-lipid complex induces a pro-inflammatory phenotype of myeloid cells. Eur J Immunol 2021; 51:965-977. [PMID: 33348422 PMCID: PMC8248127 DOI: 10.1002/eji.202048813] [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: 06/15/2020] [Revised: 11/06/2020] [Accepted: 12/18/2020] [Indexed: 12/15/2022]
Abstract
HAMLET is a protein‐lipid complex with a specific and broad bactericidal and tumoricidal activity, that lacks cytotoxic activity against healthy cells. In this study, we show that HAMLET also has general immune‐stimulatory effects on primary human monocyte‐derived dendritic cells and macrophages (Mo‐DC and Mo‐M) and murine RAW264.7 macrophages. HAMLET, but not its components alpha‐lactalbumin or oleic acid, induces mature CD14low/–CD83+ Mo‐DC and M1‐like CD14+CD86++ Mo‐M surface phenotypes. Concomitantly, inflammatory mediators, including IL‐2, IL‐6, IL‐10, IL‐12 and MIP‐1α, were released in the supernatant of HAMLET‐stimulated cells, indicating a mainly pro‐inflammatory phenotype. The HAMLET‐induced phenotype was mediated by calcium, NFκB and p38 MAPK signaling in Mo‐DCs and calcium, NFκB and ERK signaling in Mo‐M as inhibitors of these pathways almost completely blocked the induction of mature Mo‐DCs and M1‐like Mo‐M. Compared to unstimulated Mo‐DCs, HAMLET‐stimulated Mo‐DCs were more potent in inducing T cell proliferation and HAMLET‐stimulated macrophages were more efficient in phagocytosis of Streptococcus pneumoniae in vitro. This indicates a functionally activated phenotype of HAMLET‐stimulated DCs and macrophages. Combined, we propose that HAMLET has a two‐fold anti‐bacterial activity; one inducing direct cytotoxic activity, the other indirectly mediating elimination of bacteria by activation of immune cells of the myeloid lineage.
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Affiliation(s)
- Goutham Vansarla
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, Malmö, SE-214 28, Sweden
| | - Anders P Håkansson
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, Malmö, SE-214 28, Sweden
| | - Caroline Bergenfelz
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, Malmö, SE-214 28, Sweden
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7
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Zhang J, Li R, Liu Q, Zhou J, Huang H, Huang Y, Zhang Z, Wu T, Tang Q, Huang C, Zhao Y, Zhang G, Mo L, Li Y, He J. SB431542-Loaded Liposomes Alleviate Liver Fibrosis by Suppressing TGF-β Signaling. Mol Pharm 2020; 17:4152-4162. [PMID: 33089693 DOI: 10.1021/acs.molpharmaceut.0c00633] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Jinhang Zhang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Rui Li
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Qinhui Liu
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Jian Zhou
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Hui Huang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Ya Huang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Zijing Zhang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Tong Wu
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Qin Tang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Cuiyuan Huang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yingnan Zhao
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Guorong Zhang
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Li Mo
- Center of Gerontology and Geriatrics, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Yanping Li
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
| | - Jinhan He
- Laboratory of Clinical Pharmacy and Adverse Drug Reaction, West China Hospital of Sichuan University, Chengdu 610041, China
- Department of Pharmacy, West China Hospital of Sichuan University, Chengdu 610041, China
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8
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α-Lactalbumin, Amazing Calcium-Binding Protein. Biomolecules 2020; 10:biom10091210. [PMID: 32825311 PMCID: PMC7565966 DOI: 10.3390/biom10091210] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 02/06/2023] Open
Abstract
α-Lactalbumin (α-LA) is a small (Mr 14,200), acidic (pI 4–5), Ca2+-binding protein. α-LA is a regulatory component of lactose synthase enzyme system functioning in the lactating mammary gland. The protein possesses a single strong Ca2+-binding site, which can also bind Mg2+, Mn2+, Na+, K+, and some other metal cations. It contains several distinct Zn2+-binding sites. Physical properties of α-LA strongly depend on the occupation of its metal binding sites by metal ions. In the absence of bound metal ions, α-LA is in the molten globule-like state. The binding of metal ions, and especially of Ca2+, increases stability of α-LA against the action of heat, various denaturing agents and proteases, while the binding of Zn2+ to the Ca2+-loaded protein decreases its stability and causes its aggregation. At pH 2, the protein is in the classical molten globule state. α-LA can associate with membranes at neutral or slightly acidic pH at physiological temperatures. Depending on external conditions, α-LA can form amyloid fibrils, amorphous aggregates, nanoparticles, and nanotubes. Some of these aggregated states of α-LA can be used in practical applications such as drug delivery to tissues and organs. α-LA and some of its fragments possess bactericidal and antiviral activities. Complexes of partially unfolded α-LA with oleic acid are cytotoxic to various tumor and bacterial cells. α-LA in the cytotoxic complexes plays a role of a delivery carrier of cytotoxic fatty acid molecules into tumor and bacterial cells across the cell membrane. Perhaps in the future the complexes of α-LA with oleic acid will be used for development of new anti-cancer drugs.
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Pedersen JN, Frislev HKS, Pedersen JS, Otzen D. Structures and mechanisms of formation of liprotides. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2020; 1868:140505. [PMID: 32721568 DOI: 10.1016/j.bbapap.2020.140505] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/16/2020] [Indexed: 12/11/2022]
Abstract
Many proteins form complexes called liprotides with oleic acid and other cis-fatty acids under conditions where the protein is partially unfolded. The complexes vary in structure depending on the ratio of protein and lipid, but the most common structural organization is the core-shell structure, in which a layer of dynamic, partially unfolded and extended proteins surrounds a micelle-like fatty acid core. This structure, first reported for α-lactalbumin together with OA, resembles complexes formed between proteins and anionic surfactants like SDS. Liprotides first rose to fame through their anti-carcinogenic properties which still remains promising for topical applications though not yet implemented in the clinic. In addition, liprotides show potential in drug delivery thanks to the ability of the micelle core to solubilize and stabilize hydrophobic compounds, though applications are challenged by their sensitivity to acidic pH and dynamic exchange of lipids which makes them easy prey for serum "hoovers" such as albumin. However, liprotides are also of fundamental interest as a generic "protein complex structure", demonstrating the many and varied structural consequences of protein-lipid interactions. Here we provide an overview of the different types of liprotide complexes, ranging from quasi-native complexes via core-shell structures to multi-layer structures, and discuss the many conditions under which they form. Given the many variable types of complexes that can form, rigorous biophysical analysis (stoichiometry, shape and structure of the complexes) remains crucial for a complete understanding of the mechanisms of action of this fascinating group of protein-lipid complexes both in vitro and in vivo.
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Affiliation(s)
- Jannik Nedergaard Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Henriette Kristina Søster Frislev
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Novo Nordisk, Hallas Alle 1, DK-4400 Kalundborg, Denmark
| | - Jan Skov Pedersen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark
| | - Daniel Otzen
- Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus C, Denmark; Department of Molecular Biology and Genetics, Aarhus University, Gustav Wieds Vej 10C, 8000 Aarhus C, Denmark.
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Roche-Hakansson H, Vansarla G, Marks LR, Hakansson AP. The human milk protein-lipid complex HAMLET disrupts glycolysis and induces death in Streptococcus pneumoniae. J Biol Chem 2019; 294:19511-19522. [PMID: 31694917 DOI: 10.1074/jbc.ra119.009930] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/29/2019] [Indexed: 12/25/2022] Open
Abstract
HAMLET is a complex of human α-lactalbumin (ALA) and oleic acid and kills several Gram-positive bacteria by a mechanism that bears resemblance to apoptosis in eukaryotic cells. To identify HAMLET's bacterial targets, here we used Streptococcus pneumoniae as a model organism and employed a proteomic approach that identified several potential candidates. Two of these targets were the glycolytic enzymes fructose bisphosphate aldolase (FBPA) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). Treatment of pneumococci with HAMLET immediately inhibited their ATP and lactate production, suggesting that HAMLET inhibits glycolysis. This observation was supported by experiments with recombinant bacterial enzymes, along with biochemical and bacterial viability assays, indicating that HAMLET's activity is partially inhibited by high glucose-mediated stimulation of glycolysis but enhanced in the presence of the glycolysis inhibitor 2-deoxyglucose. Both HAMLET and ALA bound directly to each glycolytic enzyme in solution and solid-phase assays and effectively inhibited their enzymatic activities. In contrast, oleic acid alone had little to no inhibitory activity. However, ALA alone also exhibited no bactericidal activity and did not block glycolysis in whole cells, suggesting a role for the lipid moiety in the internalization of HAMLET into the bacterial cells to reach its target(s). This was verified by inhibition of enzyme activity in whole cells after HAMLET but not ALA exposure. The results of this study suggest that part of HAMLET's antibacterial activity relates to its ability to target and inhibit glycolytic enzymes, providing an example of a natural antimicrobial agent that specifically targets glycolysis.
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Affiliation(s)
- Hazeline Roche-Hakansson
- Department of Microbiology and Immunology, University at Buffalo, State University of New York, Buffalo, New York 14203
| | - Goutham Vansarla
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, SE-21428 Malmö, Sweden
| | - Laura R Marks
- Department of Medicine, Barnes-Jewish Hospital, Washington University, St. Louis, Missouri 63110
| | - Anders P Hakansson
- Division of Experimental Infection Medicine, Department of Translational Medicine, Lund University, SE-21428 Malmö, Sweden
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11
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HAMLET, a protein complex from human milk has bactericidal activity and enhances the activity of antibiotics against pathogenic Streptococci. Antimicrob Agents Chemother 2019:AAC.01193-19. [PMID: 31591115 DOI: 10.1128/aac.01193-19] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
HAMLET is a protein-lipid complex derived from human milk that was first described for its tumoricidal activity. Later studies showed that HAMLET also has direct bactericidal activity against select species of bacteria, with highest activity against Streptococcus pneumoniae Additionally, HAMLET in combination with various antimicrobial agents can make a broader range of antibiotic-resistant bacterial species sensitive to antibiotics. Here, we show that HAMLET has direct antibacterial activity not only against pneumococci, but also against Streptococcus pyogenes (GAS) and Streptococcus agalactiae (GBS). Analogous to pneumococci, HAMLET-treatment of GAS and GBS resulted in depolarization of the bacterial membrane followed by membrane permeabilization and death that could be inhibited by calcium and sodium transport inhibitors. Treatment of clinical antibiotic-resistant isolates of S. pneumoniae, GAS, and GBS with sublethal concentrations of HAMLET in combination with antibiotics decreased the minimal inhibitory concentrations of the respective antibiotic into the sensitive range. This effect could also be blocked by ion transport inhibitors, suggesting that HAMLET's bactericidal and combination treatment effects used similar mechanisms. Finally, we show that HAMLET potentiated the effects of erythromycin against erythromycin-resistant bacteria more effectively than it potentiated killing by penicillin G of bacteria resistant to penicillin G. These results show for the first time that HAMLET effectively kills three different species of pathogenic Streptococci using similar mechanisms and also potentiate the activity of macrolides and lincosamides more effectively than combination treatment with beta-lactams. These findings suggest a potential therapeutic role for HAMLET in repurposing antibiotics currently causing treatment failures in patients.
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