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Elli S, Raffaini G, Guerrini M, Kosakovsky Pond S, Matrosovich M. Molecular modeling and phylogenetic analyses highlight the role of amino acid 347 of the N1 subtype neuraminidase in influenza virus host range and interspecies adaptation. Front Microbiol 2023; 14:1309156. [PMID: 38169695 PMCID: PMC10758481 DOI: 10.3389/fmicb.2023.1309156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 11/29/2023] [Indexed: 01/05/2024] Open
Abstract
The N1 neuraminidases (NAs) of avian and pandemic human influenza viruses contain tyrosine and asparagine, respectively, at position 347 on the rim of the catalytic site; the biological significance of this difference is not clear. Here, we used molecular dynamics simulation to model the effects of amino acid 347 on N1 NA interactions with sialyllacto-N-tetraoses 6'SLN-LC and 3'SLN-LC, which represent NA substrates in humans and birds, respectively. Our analysis predicted that Y347 plays an important role in the NA preference for the avian-type substrates. The Y347N substitution facilitates hydrolysis of human-type substrates by resolving steric conflicts of the Neu5Ac2-6Gal moiety with the bulky side chain of Y347, decreasing the free energy of substrate binding, and increasing the solvation of the Neu5Ac2-6Gal bond. Y347 was conserved in all N1 NA sequences of avian influenza viruses in the GISAID EpiFlu database with two exceptions. First, the Y347F substitution was present in the NA of a specific H6N1 poultry virus lineage and was associated with the substitutions G228S and/or E190V/L in the receptor-binding site (RBS) of the hemagglutinin (HA). Second, the highly pathogenic avian H5N1 viruses of the Gs/Gd lineage contained sporadic variants with the NA substitutions Y347H/D, which were frequently associated with substitutions in the HA RBS. The Y347N substitution occurred following the introductions of avian precursors into humans and pigs with N/D347 conserved during virus circulation in these hosts. Comparative evolutionary analysis of site 347 revealed episodic positive selection across the entire tree and negative selection within most host-specific groups of viruses, suggesting that substitutions at NA position 347 occurred during host switches and remained under pervasive purifying selection thereafter. Our results elucidate the role of amino acid 347 in NA recognition of sialoglycan substrates and emphasize the significance of substitutions at position 347 as a marker of host range and adaptive evolution of influenza viruses.
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Affiliation(s)
- Stefano Elli
- Istituto di Ricerche Chimiche e Biochimiche ‘G. Ronzoni’, Milan, Italy
| | - Giuseppina Raffaini
- Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Milan, Italy
| | - Marco Guerrini
- Istituto di Ricerche Chimiche e Biochimiche ‘G. Ronzoni’, Milan, Italy
| | - Sergei Kosakovsky Pond
- Institute for Genomics and Evolutionary Medicine, Temple University, Philadelphia, PA, United States
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2
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Greene KS, Choi A, Chen M, Yang N, Li R, Qiu Y, Lukey MJ, Rojas KS, Shen J, Wilson KF, Katt WP, Whittaker GR, Cerione RA. Inhibiting Glutamine Metabolism Blocks Coronavirus Replication in Mammalian Cells. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.27.559756. [PMID: 37808692 PMCID: PMC10557708 DOI: 10.1101/2023.09.27.559756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Developing therapeutic strategies against COVID-19 has gained widespread interest given the likelihood that new viral variants will continue to emerge. Here we describe one potential therapeutic strategy which involves targeting members of the glutaminase family of mitochondrial metabolic enzymes (GLS and GLS2), which catalyze the first step in glutamine metabolism, the hydrolysis of glutamine to glutamate. We show three examples where GLS expression increases during coronavirus infection of host cells, and another in which GLS2 is upregulated. The viruses hijack the metabolic machinery responsible for glutamine metabolism to generate the building blocks for biosynthetic processes and satisfy the bioenergetic requirements demanded by the 'glutamine addiction' of virus-infected host cells. We demonstrate how genetic silencing of glutaminase enzymes reduces coronavirus infection and that newer members of two classes of small molecule allosteric inhibitors targeting these enzymes, designated as SU1, a pan-GLS/GLS2 inhibitor, and UP4, which is specific for GLS, block viral replication in mammalian epithelial cells. Overall, these findings highlight the importance of glutamine metabolism for coronavirus replication in human cells and show that glutaminase inhibitors can block coronavirus infection and thereby may represent a novel class of anti-viral drug candidates. Teaser Inhibitors targeting glutaminase enzymes block coronavirus replication and may represent a new class of anti-viral drugs.
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AbuBakar U, Amrani L, Kamarulzaman FA, Karsani SA, Hassandarvish P, Khairat JE. Avian Influenza Virus Tropism in Humans. Viruses 2023; 15:833. [PMID: 37112812 PMCID: PMC10142937 DOI: 10.3390/v15040833] [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: 02/04/2023] [Revised: 03/12/2023] [Accepted: 03/17/2023] [Indexed: 03/29/2023] Open
Abstract
An influenza pandemic happens when a novel influenza A virus is able to infect and transmit efficiently to a new, distinct host species. Although the exact timing of pandemics is uncertain, it is known that both viral and host factors play a role in their emergence. Species-specific interactions between the virus and the host cell determine the virus tropism, including binding and entering cells, replicating the viral RNA genome within the host cell nucleus, assembling, maturing and releasing the virus to neighboring cells, tissues or organs before transmitting it between individuals. The influenza A virus has a vast and antigenically varied reservoir. In wild aquatic birds, the infection is typically asymptomatic. Avian influenza virus (AIV) can cross into new species, and occasionally it can acquire the ability to transmit from human to human. A pandemic might occur if a new influenza virus acquires enough adaptive mutations to maintain transmission between people. This review highlights the key determinants AIV must achieve to initiate a human pandemic and describes how AIV mutates to establish tropism and stable human adaptation. Understanding the tropism of AIV may be crucial in preventing virus transmission in humans and may help the design of vaccines, antivirals and therapeutic agents against the virus.
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Affiliation(s)
- Umarqayum AbuBakar
- Institute of Biological Sciences (ISB), Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Lina Amrani
- Institute of Biological Sciences (ISB), Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Farah Ayuni Kamarulzaman
- Institute of Biological Sciences (ISB), Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Saiful Anuar Karsani
- Institute of Biological Sciences (ISB), Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Pouya Hassandarvish
- Tropical Infectious Diseases Research and Education Center, Universiti Malaya, Kuala Lumpur 50603, Malaysia
| | - Jasmine Elanie Khairat
- Institute of Biological Sciences (ISB), Faculty of Science, Universiti Malaya, Kuala Lumpur 50603, Malaysia
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4
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Saso W, Yamasaki M, Nakakita SI, Fukushi S, Tsuchimoto K, Watanabe N, Sriwilaijaroen N, Kanie O, Muramatsu M, Takahashi Y, Matano T, Takeda M, Suzuki Y, Watashi K. Significant role of host sialylated glycans in the infection and spread of severe acute respiratory syndrome coronavirus 2. PLoS Pathog 2022; 18:e1010590. [PMID: 35700214 PMCID: PMC9197039 DOI: 10.1371/journal.ppat.1010590] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 05/13/2022] [Indexed: 12/23/2022] Open
Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been transmitted across all over the world, in contrast to the limited epidemic of genetically- and virologically-related SARS-CoV. However, the molecular basis explaining the difference in the virological characteristics among SARS-CoV-2 and SARS-CoV has been poorly defined. Here we identified that host sialoglycans play a significant role in the efficient spread of SARS-CoV-2 infection, while this was not the case with SARS-CoV. SARS-CoV-2 infection was significantly inhibited by α2-6-linked sialic acid-containing compounds, but not by α2–3 analog, in VeroE6/TMPRSS2 cells. The α2-6-linked compound bound to SARS-CoV-2 spike S1 subunit to competitively inhibit SARS-CoV-2 attachment to cells. Enzymatic removal of cell surface sialic acids impaired the interaction between SARS-CoV-2 spike and angiotensin-converting enzyme 2 (ACE2), and suppressed the efficient spread of SARS-CoV-2 infection over time, in contrast to its least effect on SARS-CoV spread. Our study provides a novel molecular basis of SARS-CoV-2 infection which illustrates the distinctive characteristics from SARS-CoV. SARS-CoV-2, which has been highly transmissible and rapidly spreading worldwide, has caused approximately 458 million confirmed cases of COVID-19 with more than 6 million deaths by March 2022. Here we found that SARS-CoV-2 infection was significantly inhibited by α2-6-linked sialic acid-containing compounds and by depletion of cell surface sialic acid with only a minor effect on SARS-CoV infection. We identified that SARS-CoV-2 spike S1 subunit directly binds to α2-6-linked sialoglycans for efficient attachment to host cell surface. Our finding indicated that host sialoglycans play a significant role in the efficient infection of SARS-CoV-2, which provides a novel understanding of the molecular basis explaining the rapid spread of SARS-CoV-2 over SARS-CoV.
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Affiliation(s)
- Wakana Saso
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Masako Yamasaki
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
- Department of Applied Biological Sciences, Tokyo University of Science, Noda, Japan
| | - Shin-ichi Nakakita
- Department of Functional Glycomics, Life Science Research Center, Kagawa University, Kagawa, Japan
| | - Shuetsu Fukushi
- Department of Virology I, National Institute of Infectious Diseases, Tokyo, Japan
| | - Kana Tsuchimoto
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
| | - Noriyuki Watanabe
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Nongluk Sriwilaijaroen
- Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani, Thailand
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Osamu Kanie
- Micro/Nano Technology Center and Department of Applied Biochemistry, Tokai University, Kanagawa, Japan
| | - Masamichi Muramatsu
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yoshimasa Takahashi
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
| | - Tetsuro Matano
- The Institute of Medical Science, The University of Tokyo, Tokyo, Japan
- AIDS Research Center, National Institute of Infectious Diseases, Tokyo, Japan
| | - Makoto Takeda
- Department of Virology III, National Institute of Infectious Diseases, Tokyo, Japan
| | - Yasuo Suzuki
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
- * E-mail: (Y.S); (K.W)
| | - Koichi Watashi
- Department of Virology II, National Institute of Infectious Diseases, Tokyo, Japan
- Department of Applied Biological Sciences, Tokyo University of Science, Noda, Japan
- Research Center for Drug and Vaccine Development, National Institute of Infectious Diseases, Tokyo, Japan
- Institute for Frontier Life and Medical Sciences, Kyoto University, Kyoto, Japan
- MIRAI, JST, Saitama, Japan
- * E-mail: (Y.S); (K.W)
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Sriwilaijaroen N, Suzuki Y. Roles of Sialyl Glycans in HCoV-OC43, HCoV-HKU1, MERS-CoV and SARS-CoV-2 Infections. Methods Mol Biol 2022; 2556:243-271. [PMID: 36175638 DOI: 10.1007/978-1-0716-2635-1_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Ongoing seasonal HCoV-OC43 and HCoV-HKU1 (common cold), an ongoing zoonotic infection of highly lethal MERS-CoV in humans (MERS disease), and an ongoing pandemic SARS-CoV-2 (COVID-19) with high mutability giving some variants causing severe illness and death have been reported to attach to sialyl receptors via their spike (S) glycoproteins and via additional short spikes, hemagglutinin-esterase (HE) glycoproteins, for HCoV-OC43 and HCoV-HKU1. There is lack of zoonotic viruses that are origins of HCoV-HKU1 and the first recorded pandemic CoV (SARS-CoV-2) for studies. In this chapter, we review current knowledge of the roles of sialyl glycans in infections with these viruses in distinct infection stages. Determination of the similarities and differences in roles of sialyl glycans in infections with these viruses could lead to a better understanding of the pathogenesis and transmission that is essential for combating infections with CoVs that recognize sialyl glycans.
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Affiliation(s)
- Nongluk Sriwilaijaroen
- Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani, Thailand
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | - Yasuo Suzuki
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan.
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6
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Sriwilaijaroen N, Suzuki Y. Roles of Glycans and Non-glycans on the Epithelium and in the Immune System in H1-H18 Influenza A Virus Infections. Methods Mol Biol 2022; 2556:205-242. [PMID: 36175637 DOI: 10.1007/978-1-0716-2635-1_16] [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] [Indexed: 06/16/2023]
Abstract
The large variation of influenza A viruses (IAVs) in various susceptible hosts and their rapid evolution, which allows host/tissue switching, host immune escape, vaccine escape, and drug resistance, are difficult challenges for influenza control in all countries worldwide. Access and binding of the IAV to actual receptors at endocytic sites is critical for the establishment of influenza infection. In this chapter, the progress in identification of and roles of glycans and non-glycans on the epithelium and in the immune system in H1-H18 IAV infections are reviewed. The first part of the review is on current knowledge of H1-H16 IAV receptors on the epithelium including sialyl glycans, other negatively charged glycans, and annexins. The second part of the review focuses on H1-H16 IAV receptors in the immune system including acidic surfactant phospholipids, Sia on surfactant proteins, the carbohydrate recognition domain (CRD) of surfactant proteins, Sia on mucins, Sia and C-type lectins on macrophages and dendritic cells, and Sia on NK cells. The third part of the review is about a possible H17-H18 IAV receptor. Binding of these receptors to IAVs may result in inhibition or enhancement of IAV infection depending on their location, host cell type, and IAV strain. Among these receptors, host sialyl glycans are key determinants of viral hemagglutinin (HA) lectins for H1-H16 infections. HA must acquire mutations to bind to sialyl glycans that are dominant on a new target tissue when switching to a new host for efficient transmission and to bind to long sialyl glycans found in the case of seasonal HAs with multiple glycosylation sites as a consequence of immune evasion. Although sialyl receptors/C-type lectins on immune cells are decoy receptors/pathogen recognition receptors for capturing viral HA lectin/glycans protecting HA antigenic sites, some IAV strains do not escape, such as by release with neuraminidase, but hijack these molecules to gain entry and replication in immune cells. An understanding of the virus-host battle tactics at the receptor level might lead to the establishment of novel strategies for effective control of influenza.
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Affiliation(s)
- Nongluk Sriwilaijaroen
- Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani, Thailand.
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan.
| | - Yasuo Suzuki
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
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7
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Matrosovich MN, Gambaryan AS. Characterization of Influenza Virus Binding to Receptors on Isolated Cell Membranes. Methods Mol Biol 2022; 2556:149-168. [PMID: 36175633 DOI: 10.1007/978-1-0716-2635-1_12] [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] [Indexed: 06/16/2023]
Abstract
An interplay between receptor-binding properties of influenza viruses (IVs) and spectrum of sialic acid-containing receptors on target cells in birds and mammals determine viral host range, tissue tropism, and pathogenicity. Here, we describe method that allows to characterize binding of IVs to biologically relevant cellular receptors using a conventional solid-phase enzyme-linked assay. In this method, we isolate plasma membranes from respiratory and intestinal epithelial cells of animal origin (Subheading 3.2). We adsorb the membranes in the wells of 96-well ELISA plates, incubate the membrane-coated wells with serially diluted IVs, and determine amounts of IVs attached to the membranes using viral ability to bind peroxidase-labeled sialoglycoprotein fetuin. Based on the concentration dependence of IV binding to the membrane, we estimate binding avidity and number of binding sites. We describe two variants of the assay in Subheadings 3.6 and 3.7 and provide examples.
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Affiliation(s)
| | - Alexandra S Gambaryan
- Chumakov Federal Scientific Center for Research and Development of Immune-and-Biological Products, Russian Academy of Sciences, Moscow, Russia
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8
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Abstract
Depending on the strain, influenza A virus causes animal, zoonotic, pandemic, or seasonal influenza with varying degrees of severity. Two surface glycoprotein spikes, hemagglutinin (HA) and neuraminidase (NA), are the most important influenza A virus antigens. NA plays an important role in the propagation of influenza virus by removing terminal sialic acid from sialyl decoy receptors and thereby facilitating the release of viruses from traps such as in mucus and on infected cells. Some NA inhibitors have become widely used drugs for treatment of influenza. However, attempts to develop effective and safe NA inhibitors that can be used for treatment of anti-NA drugs-resistant influenza viruses have continued. In this chapter, we describe the following updates on influenza A NA inhibitor development: (i) N-acetylneuraminic acid (Neu5Ac)-based derivatives, (ii) covalent NA inhibitors, (iii) sulfo-sialic acid analogs, (iv) N-acetyl-6-sulfo-β-D-glucosaminide-based inhibitors, (v) inhibitors targeting the 150-loop of group 1 NAs, (vi) conjugation inhibitors, (vii) acylhydrazone derivatives, (viii) monoclonal antibodies, (ix) PVP-I, and (x) natural products. Finally, we provide future perspectives on the next-generation anti-NA drugs.
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Affiliation(s)
- Nongluk Sriwilaijaroen
- Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani, Thailand
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan
| | | | - Hiromasa Kiyota
- Graduate School of Environmental and Life Science, Okayama University, Okayama, Japan
| | - Yasuo Suzuki
- Department of Medical Biochemistry, School of Pharmaceutical Sciences, University of Shizuoka, Shizuoka, Japan.
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Bell TAS, Velappan N, Gleasner CD, Xie G, Starkenburg SR, Waldo G, Banerjee S, Micheva-Viteva SN. Non-classical autophagy activation pathways are essential for production of infectious Influenza A virus in vitro. Mol Microbiol 2021; 117:508-524. [PMID: 34931347 PMCID: PMC9305535 DOI: 10.1111/mmi.14865] [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] [Received: 12/07/2021] [Accepted: 12/15/2021] [Indexed: 11/28/2022]
Abstract
Autophagy is a critical mechanism deployed by eukaryotic cells in response to stress, including viral infection, to boost the innate antimicrobial responses. However, an increasing number of pathogens hijack the autophagic machinery to facilitate their own replication. Influenza A virus (IAV), responsible for several global pandemics, has an intricate dependence on autophagy for successful replication in mammalian cells. To elucidate key chokepoints in the host stress responses facilitating IAV replication, we constructed a meta‐transcriptome of IAV and host gene expression dynamics during early (1–3 hpi), mid (4–6 hpi), and late (8–12 hpi) stages of the viral replication cycle at two multiplicities of infection (MOI): 1 and 5. We supplemented the global transcriptome study with phosphoproteomic analysis of stress‐activated protein kinase (SAPK/JNK) signaling in lung carcinoma (predominantly used as an in vitro model of IAV replication) and normal human bronchial epithelial cells. We report significant differences in the activation profiles of autophagy regulating genes upon IAV infection at the two MOI as well as divergent dependence on ULK1 signaling within the normal and cancer cells. Regardless of the cell model, JNK‐Thr187 signaling was crucial for the production of infectious viral particles.
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Affiliation(s)
- Tisza A S Bell
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Nileena Velappan
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Cheryl D Gleasner
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Gang Xie
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Shawn R Starkenburg
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Geoffrey Waldo
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
| | - Shounak Banerjee
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
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Chen L, Lei Y, Zhang L. Role of C-X-C motif chemokine ligand 14 promoter region DNA methylation and single nucleotide polymorphism in influenza A severity. Respir Med 2021; 185:106462. [PMID: 34082276 DOI: 10.1016/j.rmed.2021.106462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/06/2021] [Accepted: 05/06/2021] [Indexed: 01/11/2023]
Abstract
OBJECTIVE The purpose of our experiment is to discuss the function of DNA methylation and single nucleotide polymorphism (SNP) in C-X-C motif chemokine ligand 14 (CXCL14) promoter region in influenza A (H1N1) severity. METHODS Clinic data and blood samples from H1N1 patients were collected. Blood routine indexes were measured. Levels of T lymphocytes were assessed. Importantly, CXCL14 expression and methylation in H1N1 patients and A549 cells were detected through functional assays. Additionally, rs2237061, rs2237062 and rs2547 of CXCL14 were genotyped to analyze the relation of CXCL14 SNP and H1N1 severity. RESULTS The number of leukocytes, neutrophils and lymphocytes as well as T lymphocytes in H1N1 patients was lower than that in healthy subjects, and that was decreased in severe H1N1 patients compared with the mild H1N1 patients. In HIN1 patients, CXCL14 expression was decreased, while CXCL14 methylation was increased, and CXCL14 expression was further decreased and CXCL14 methylation was further increased in severe H1N1 patients. CXCL14 methylation was negatively correlated with T lymphocytes in H1N1 patients. CXCL14 methylation was elevated in H1N1-infected A549 cells. GA and AA genotypes of rs2547 in CXCL14 were risky genotypes for H1N1, and AA genotype was risky genotype for severe H1N1. Number of T lymphocytes was lower in H1N1 patients carrying AA genotype of rs2547 than that in GA + GG genotype. CONCLUSION CXCL14 promoter region DNA methylation and SNP were correlated with H1N1 severity.
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Affiliation(s)
- Liang Chen
- Department of Infectious Disease, Beijing Jishuitan Hospital, 4th Medical College of Peking University, Beijing 100096, China
| | - Yan Lei
- North District Department of Respiration, Air Force 986th Hospital, Xi'an, Shaanxi Province 710054, China
| | - Lingling Zhang
- Clinical Laboratory, Hospital of Chengdu University of Traditional Chinese Medicine, Chengdu, Sichuan Province 610072, China.
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