{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,29]],"date-time":"2026-03-29T10:10:52Z","timestamp":1774779052539,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,12,6]],"date-time":"2019-12-06T00:00:00Z","timestamp":1575590400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Research Foundation, South Africa","award":["104837"],"award-info":[{"award-number":["104837"]}]},{"DOI":"10.13039\/501100001321","name":"National Research Foundation","doi-asserted-by":"publisher","award":["105887"],"award-info":[{"award-number":["105887"]}],"id":[{"id":"10.13039\/501100001321","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001323","name":"Poliomyelitis Research Foundation","doi-asserted-by":"publisher","award":["18\/21"],"award-info":[{"award-number":["18\/21"]}],"id":[{"id":"10.13039\/501100001323","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Infection by oncogenic human papillomavirus (HPV) is the principle cause of cervical cancer and other anogenital cancers. The majority of cervical cancer cases occur in low- and middle-income countries (LMIC). Prophylactic vaccines exist to combat HPV infection but accessibility to these in LMIC is limited. Alternative preventative measures against HPV infection are therefore also needed to control cervical cancer risk. HPV employs multiple mechanisms to evade the host immune response. Therefore, an approach to promote HPV recognition by the immune system can reduce infection. Surfactant proteins A and D (SP-A and SP-D) are highly effective innate opsonins of pathogens. Their function is primarily understood in the lung, but they are also expressed at other sites of the body, including the female reproductive tract (FRT). We hypothesized that raised levels of SP-A and\/or SP-D may enhance immune recognition of HPV and reduce infection. Co-immunoprecipitation and flow cytometry experiments showed that purified human SP-A protein directly bound HPV16 pseudovirions (HPV16-PsVs), and the resulting HPV16-PsVs\/SP-A complex enhanced uptake of HPV16-PsVs by RAW264.7 murine macrophages. In contrast, a recombinant fragment of human SP-D bound HPV16-PsVs weakly and had no effect on viral uptake. To assess if SP-A modulates HPV16-PsVs infection in vivo, a murine cervicovaginal challenge model was applied. Surprisingly, neither na\u00efve nor C57BL\/6 mice challenged with HPV16-PsVs expressed SP-A in the FRT. However, pre-incubation of HPV16-PsVs with purified human SP-A at a 1:10 (w\/w) ratio significantly reduced the level of HPV16-PsV infection. When isolated cells from FRTs of na\u00efve C57BL\/6 mice were incubated with HPV16-PsVs and stained for selected innate immune cell populations by flow cytometry, significant increases in HPV16-PsVs uptake by eosinophils, neutrophils, monocytes, and macrophages were observed over time using SP-A-pre-adsorbed virions compared to control particles. This study is the first to describe a biochemical and functional association of HPV16 virions with the innate immune molecule SP-A. We show that SP-A impairs HPV16-PsVs infection and propose that SP-A is a potential candidate for use in topical microbicides which provide protection against new HPV infections.<\/jats:p>","DOI":"10.3390\/pathogens8040288","type":"journal-article","created":{"date-parts":[[2019,12,6]],"date-time":"2019-12-06T10:41:44Z","timestamp":1575628904000},"page":"288","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":16,"title":["Surfactant Protein A Impairs Genital HPV16 Pseudovirus Infection by Innate Immune Cell Activation in A Murine Model"],"prefix":"10.3390","volume":"8","author":[{"given":"Sylvia","family":"Ujma","sequence":"first","affiliation":[{"name":"Division of Medical Biochemistry and Structural Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7925, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sinead","family":"Carse","sequence":"additional","affiliation":[{"name":"Division of Medical Biochemistry and Structural Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7925, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alisha","family":"Chetty","sequence":"additional","affiliation":[{"name":"Division of Immunology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William","family":"Horsnell","sequence":"additional","affiliation":[{"name":"Division of Immunology, Department of Pathology, University of Cape Town, Cape Town 7925, South Africa"},{"name":"Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa"},{"name":"Institute of Microbiology and Infection, University of Birmingham, Birmingham B15 2TT, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Howard","family":"Clark","sequence":"additional","affiliation":[{"name":"Institute for Women\u2019s Health, University College London, London WC1E 6BT, UK"},{"name":"Child Health, Division of Clinical and Experimental Sciences, Department of Child Health, University of Southampton, Southampton SO17 1BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jens","family":"Madsen","sequence":"additional","affiliation":[{"name":"Institute for Women\u2019s Health, University College London, London WC1E 6BT, UK"},{"name":"Child Health, Division of Clinical and Experimental Sciences, Department of Child Health, University of Southampton, Southampton SO17 1BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Rose-Marie","family":"Mackay","sequence":"additional","affiliation":[{"name":"Child Health, Division of Clinical and Experimental Sciences, Department of Child Health, University of Southampton, Southampton SO17 1BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6735-2567","authenticated-orcid":false,"given":"Alastair","family":"Watson","sequence":"additional","affiliation":[{"name":"Child Health, Division of Clinical and Experimental Sciences, Department of Child Health, University of Southampton, Southampton SO17 1BJ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mark","family":"Griffiths","sequence":"additional","affiliation":[{"name":"National Heart &amp; Lung Institute, Imperial College London, London SW7 2AZ, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Arieh A.","family":"Katz","sequence":"additional","affiliation":[{"name":"Division of Medical Biochemistry and Structural Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7925, South Africa"},{"name":"Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa"},{"name":"SAMRC\/UCT Gynaecological Cancer Research Centre (GCRC), Cape Town 7925, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1044-3828","authenticated-orcid":false,"given":"Georgia","family":"Sch\u00e4fer","sequence":"additional","affiliation":[{"name":"Division of Medical Biochemistry and Structural Biology, Department of Integrative Biomedical Sciences, University of Cape Town, Cape Town 7925, South Africa"},{"name":"Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town 7925, South Africa"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,12,6]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2592","DOI":"10.3390\/v7052592","article-title":"Interaction of human tumor viruses with host cell surface receptors and cell entry","volume":"7","author":"Blumenthal","year":"2015","journal-title":"Viruses"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"342","DOI":"10.1038\/nrc798","article-title":"Papillomaviruses and cancer: From basic studies to clinical application","volume":"2","year":"2002","journal-title":"Nat. Rev. Cancer"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"E359","DOI":"10.1002\/ijc.29210","article-title":"Cancer incidence and mortality worldwide: Sources, methods and major patterns in globocan 2012","volume":"136","author":"Ferlay","year":"2015","journal-title":"Int. J. Cancer"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"F32","DOI":"10.1016\/j.vaccine.2012.07.092","article-title":"The burden of human papillomavirus infections and related diseases in sub-saharan africa","volume":"31","author":"Alemany","year":"2013","journal-title":"Vaccine"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"579","DOI":"10.3390\/jcm4040579","article-title":"The interaction between human immunodeficiency virus and human papillomaviruses in heterosexuals in africa","volume":"4","author":"Williamson","year":"2015","journal-title":"J. Clin. Med."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"728","DOI":"10.1245\/s10434-014-4344-8","article-title":"Control of cancer of the cervix in low- and middle-income countries","volume":"22","author":"Denny","year":"2015","journal-title":"Ann. Surg. Oncol."},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Buck, C.B., Thompson, C.D., Roberts, J.N., Muller, M., Lowy, D.R., and Schiller, J.T. (2006). Carrageenan is a potent inhibitor of papillomavirus infection. PLoS Pathog., 2.","DOI":"10.1371\/journal.ppat.0020069"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"857","DOI":"10.1038\/nm1598","article-title":"Genital transmission of hpv in a mouse model is potentiated by nonoxynol-9 and inhibited by carrageenan","volume":"13","author":"Roberts","year":"2007","journal-title":"Nat. Med."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"1219","DOI":"10.3851\/IMP1890","article-title":"The effectiveness of carraguard, a vaginal microbicide, in protecting women against high-risk human papillomavirus infection","volume":"16","author":"Marais","year":"2011","journal-title":"Antivir. Ther."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"358","DOI":"10.1128\/AAC.05461-11","article-title":"Zinc acetate\/carrageenan gels exhibit potent activity in vivo against high-dose herpes simplex virus 2 vaginal and rectal challenge","volume":"56","author":"Abraham","year":"2012","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1977","DOI":"10.1016\/S0140-6736(08)61842-5","article-title":"Efficacy of carraguard for prevention of hiv infection in women in South Africa: A randomised, double-blind, placebo-controlled trial","volume":"372","author":"Ramjee","year":"2008","journal-title":"Lancet"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1186\/1750-9378-5-19","article-title":"Hpv\u2014Immune response to infection and vaccination","volume":"5","author":"Stanley","year":"2010","journal-title":"Infect. Agents Cancer"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1159\/000492974","article-title":"Surfactant proteins a and d: Trimerized innate immunity proteins with an affinity for viral fusion proteins","volume":"11","author":"Watson","year":"2019","journal-title":"J. Innate Immun."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"7005","DOI":"10.1128\/IAI.01402-06","article-title":"Surfactant protein d increases fusion of mycobacterium tuberculosis-containing phagosomes with lysosomes in human macrophages","volume":"74","author":"Ferguson","year":"2006","journal-title":"Infect. Immun."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"5343","DOI":"10.4049\/jimmunol.155.11.5343","article-title":"Pulmonary surfactant protein a mediates enhanced phagocytosis of mycobacterium tuberculosis by a direct interaction with human macrophages","volume":"155","author":"Gaynor","year":"1995","journal-title":"J. Immunol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"2009","DOI":"10.1086\/315134","article-title":"Surfactant protein a binds to the fusion glycoprotein of respiratory syncytial virus and neutralizes virion infectivity","volume":"180","author":"Ghildyal","year":"1999","journal-title":"J. Infect. Dis."},{"key":"ref_17","first-page":"L1156","article-title":"Mechanisms of anti-influenza activity of surfactant proteins a and d: Comparison with serum collectins","volume":"273","author":"Hartshorn","year":"1997","journal-title":"Am. J. Physiol."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1165\/rcmb.2003-0107OC","article-title":"Surfactant protein-d enhances phagocytosis and pulmonary clearance of respiratory syncytial virus","volume":"31","author":"LeVine","year":"2004","journal-title":"Am. J. Respir. Cell Mol. Biol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"3934","DOI":"10.4049\/jimmunol.165.7.3934","article-title":"Distinct effects of surfactant protein a or d deficiency during bacterial infection on the lung","volume":"165","author":"LeVine","year":"2000","journal-title":"J. Immunol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"5868","DOI":"10.4049\/jimmunol.167.10.5868","article-title":"Surfactant protein d enhances clearance of influenza a virus from the lung in vivo","volume":"167","author":"LeVine","year":"2001","journal-title":"J. Immunol."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"3171","DOI":"10.1128\/iai.65.8.3171-3179.1997","article-title":"Binding of pulmonary surfactant proteins a and d to aspergillus fumigatus conidia enhances phagocytosis and killing by human neutrophils and alveolar macrophages","volume":"65","author":"Madan","year":"1997","journal-title":"Infect. Immun."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Thawer, S., Auret, J., Schnoeller, C., Chetty, A., Smith, K., Darby, M., Roberts, L., Mackay, R.M., Whitwell, H.J., and Timms, J.F. (2016). Surfactant protein-d is essential for immunity to helminth infection. PLoS Pathog., 12.","DOI":"10.1371\/journal.ppat.1005461"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"3","DOI":"10.1159\/000451026","article-title":"Non-pulmonary immune functions of surfactant proteins a and d","volume":"9","author":"Ujma","year":"2017","journal-title":"J. Innate Immun."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1016\/j.jaci.2008.10.014","article-title":"Protective role of the lung collectins surfactant protein a and surfactant protein d in airway inflammation","volume":"122","author":"Haczku","year":"2008","journal-title":"J. Allergy Clin. Immunol."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1293","DOI":"10.1016\/j.molimm.2005.08.004","article-title":"Surfactant proteins sp-a and sp-d: Structure, function and receptors","volume":"43","author":"Kishore","year":"2006","journal-title":"Mol. Immunol."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1129","DOI":"10.2741\/4168","article-title":"Ligands and receptors of lung surfactant proteins sp-a and sp-d","volume":"18","author":"Qaseem","year":"2013","journal-title":"Front. Biosci."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"58","DOI":"10.1038\/nri1528","article-title":"Immunoregulatory functions of surfactant proteins","volume":"5","author":"Wright","year":"2005","journal-title":"Nat. Rev. Immunol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"348","DOI":"10.1095\/biolreprod.108.068338","article-title":"Surfactant protein a signaling pathways in human uterine smooth muscle cells","volume":"79","author":"Tanfin","year":"2008","journal-title":"Biol. Reprod."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"149","DOI":"10.1093\/molehr\/gah022","article-title":"Surfactant protein d in the female genital tract","volume":"10","author":"Floridon","year":"2004","journal-title":"Mol. Hum. Reprod."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1111\/j.1365-2567.2004.01782.x","article-title":"Surfactant protein a, an innate immune factor, is expressed in the vaginal mucosa and is present in vaginal lavage fluid","volume":"111","author":"MacNeill","year":"2004","journal-title":"Immunology"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"197","DOI":"10.1016\/j.molimm.2015.03.001","article-title":"Decidual expression and localization of human surfactant protein sp-a and sp-d, and complement protein c1q","volume":"66","author":"Madhukaran","year":"2015","journal-title":"Mol. Immunol."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"601","DOI":"10.4049\/jimmunol.181.1.601","article-title":"Surfactant protein a binds to hiv and inhibits direct infection of cd4+ cells, but enhances dendritic cell-mediated viral transfer","volume":"181","author":"Gaiha","year":"2008","journal-title":"J. Immunol."},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Madsen, J., Gaiha, G.D., Palaniyar, N., Dong, T., Mitchell, D.A., and Clark, H.W. (2013). Surfactant protein d modulates hiv infection of both t-cells and dendritic cells. PLoS ONE, 8.","DOI":"10.1371\/journal.pone.0059047"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"861","DOI":"10.1093\/molehr\/gah117","article-title":"Surfactant protein d is present in the human female reproductive tract and inhibits chlamydia trachomatis infection","volume":"10","author":"Oberley","year":"2004","journal-title":"Mol. Hum. Reprod."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"S12","DOI":"10.1016\/j.ygyno.2010.04.004","article-title":"Current understanding of the mechanism of hpv infection","volume":"118","author":"Schiller","year":"2010","journal-title":"Gynecol. Oncol."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"551","DOI":"10.1016\/j.imbio.2009.09.005","article-title":"The human lung surfactant proteins a (sp-a) and d (sp-d) interact with apoptotic target cells by different binding mechanisms","volume":"215","author":"Jakel","year":"2010","journal-title":"Immunobiology"},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Roberts, J.N. (2007). Infection of murine vaginal or endocervical mucosa with human papillomavirus pseudovirions. Nat. Protoc.","DOI":"10.1038\/nprot.2007.235"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"13125","DOI":"10.1128\/JVI.77.24.13125-13135.2003","article-title":"Different heparan sulfate proteoglycans serve as cellular receptors for human papillomaviruses","volume":"77","author":"Handisurya","year":"2003","journal-title":"J. Virol."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"639","DOI":"10.2174\/157016209789973682","article-title":"Increased ccl2 expression and macrophage\/monocyte migration during microbicide-induced vaginal irritation","volume":"7","author":"Alt","year":"2009","journal-title":"Curr. HIV Res."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"145","DOI":"10.1177\/1753425909360552","article-title":"Surfactant protein-a enhances ureaplasmacidal activity in vitro","volume":"17","author":"Chesko","year":"2011","journal-title":"Innate Immun."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"L296","DOI":"10.1152\/ajplung.00440.2003","article-title":"Surfactant proteins a and d enhance the phagocytosis of chlamydia into thp-1 cells","volume":"287","author":"Oberley","year":"2004","journal-title":"Am. J. Physiol. Lung Cell. Mol. Physiol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"43254","DOI":"10.1074\/jbc.M305628200","article-title":"Crystal structure of trimeric carbohydrate recognition and neck domains of surfactant protein a","volume":"278","author":"Head","year":"2003","journal-title":"J. Biol. Chem."},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"2898","DOI":"10.4049\/jimmunol.1502626","article-title":"Surfactant protein a inhibits growth and adherence of uropathogenic escherichia coli to protect the bladder from infection","volume":"198","author":"Hashimoto","year":"2017","journal-title":"J. Immunol."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"863","DOI":"10.1093\/molehr\/gam074","article-title":"Regulation of surfactant protein d in the mouse female reproductive tract in vivo","volume":"13","author":"Oberley","year":"2007","journal-title":"Mol. Hum. Reprod."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1016\/j.imbio.2015.09.019","article-title":"Expression of surfactant proteins sp-a and sp-d in murine decidua and immunomodulatory effects on decidual macrophages","volume":"221","author":"Madhukaran","year":"2016","journal-title":"Immunobiology"},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"116","DOI":"10.1016\/j.rmed.2017.03.030","article-title":"Recurrent respiratory papillomatosis: A state-of-the-art review","volume":"126","author":"Fortes","year":"2017","journal-title":"Respir. Med."},{"key":"ref_47","first-page":"445","article-title":"Generation of hpv pseudovirions using transfection and their use in neutralization assays","volume":"119","author":"Buck","year":"2005","journal-title":"Methods Mol. Med."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1016\/j.imbio.2016.10.015","article-title":"Novel expression of a functional trimeric fragment of human sp-a with efficacy in neutralisation of rsv","volume":"222","author":"Watson","year":"2017","journal-title":"Immunobiology"},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"1585","DOI":"10.1128\/IAI.01239-15","article-title":"Crystal structure of a complex of surfactant protein d (sp-d) and haemophilus influenzae lipopolysaccharide reveals shielding of core structures in sp-d-resistant strains","volume":"84","author":"Clark","year":"2016","journal-title":"Infect. Immun."},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"e00307-17","DOI":"10.1128\/JVI.00307-17","article-title":"Vimentin modulates infectious internalisation of hpv16 pseudovirions","volume":"91","author":"Graham","year":"2017","journal-title":"J. Virol."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"455","DOI":"10.1111\/j.1600-0854.2011.01320.x","article-title":"Human papillomavirus l2 facilitates viral escape from late endosomes via sorting nexin 17","volume":"13","author":"Ozbun","year":"2012","journal-title":"Traffic"},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"4558","DOI":"10.1128\/JVI.77.8.4558-4565.2003","article-title":"Progesterone increases susceptibility and decreases immune responses to genital herpes infection","volume":"77","author":"Kaushic","year":"2003","journal-title":"J. Virol."}],"container-title":["Pathogens"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-0817\/8\/4\/288\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T13:40:50Z","timestamp":1760190050000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-0817\/8\/4\/288"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2019,12,6]]},"references-count":52,"journal-issue":{"issue":"4","published-online":{"date-parts":[[2019,12]]}},"alternative-id":["pathogens8040288"],"URL":"https:\/\/doi.org\/10.3390\/pathogens8040288","relation":{},"ISSN":["2076-0817"],"issn-type":[{"value":"2076-0817","type":"electronic"}],"subject":[],"published":{"date-parts":[[2019,12,6]]}}}