{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,30]],"date-time":"2026-07-30T15:23:25Z","timestamp":1785425005508,"version":"3.56.0"},"reference-count":34,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T00:00:00Z","timestamp":1784505600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001503","name":"Indian Council of Agricultural Research","doi-asserted-by":"crossref","award":["BGAM-9005"],"award-info":[{"award-number":["BGAM-9005"]}],"id":[{"id":"10.13039\/501100001503","id-type":"DOI","asserted-by":"crossref"}]},{"award":["BGAM-9005"],"award-info":[{"award-number":["BGAM-9005"]}],"id":[{"id":"https:\/\/ror.org\/04fw54a43","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Department of Agricultural Research and Education (DARE), Ministry of Agriculture and Farmers Welfare"},{"id":[{"id":"https:\/\/ror.org\/01d1n9n57","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>Background: Equine herpesvirus type 1 (EHV-1) and equine influenza virus (EIV) are major respiratory pathogens in horses, causing significant economic losses in domesticated horses. Bacterial Artificial Chromosome (BAC) technology can be used to precisely manipulate the EHV-1 genome for the development of live-attenuated vector vaccines. Earlier, our group developed a live-attenuated EHV-1 vaccine by deleting virulence-associated genes using this technology and the mutant EHV-1 has been exploited for expressing foreign gene in the current study. Specifically, in this study, a mutant EHV-1 virus expressing the hemagglutinin (HA) gene of H3N8 EIV (sub-lineage: Florida clade 2) was generated and characterized in vitro. Methods: The HA gene of EIV (Florida clade 2) was used for antigen gene cloning. The expression cassette for the HA gene was commercially synthesized and inserted into the backbone of EHV1\u2206IR6 BAC using an En passant mutagenesis strategy. Recombinant clones were selected using antibiotic selection, PCR, and RFLP. Further, the recombinant virus was regenerated in RK-13 cells via transfection and characterized in vitro for plaque size, growth kinetics and immunofluorescence antibody test (IFAT). Results: PCR and RFLP confirmed the successful insertion of the HA gene into pEHV1\u2206IR6\/gE BAC. The recombinant virus, vEHV1\u2206IR6\/gE-HA(FC2), was successfully rescued in RK13 cells and demonstrated expression of the EIV haemagglutinin proteins by immunofluorescence assay. Although plaque size was reduced in the generated mutant virus in comparison to parental virus, the growth kinetics of the recombinant viruses were comparable to those of vEHV1\u2206IR6\/gE. Conclusions: These findings demonstrate the successful expression of immunodominant hemagglutinin protein of EIV by recombinant EHV-1 and indicate the potential suitability of EHV-1 BAC as a vector platform for foreign gene expression.<\/jats:p>","DOI":"10.3390\/vaccines14070634","type":"journal-article","created":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T10:44:02Z","timestamp":1784544242000},"page":"634","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Recombinant EHV-1 Vector Expressing Immunodominant Hemagglutinin Protein of Equine Influenza Virus H3N8 (Sub-Lineage Florida Clade 2)"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9134-0737","authenticated-orcid":false,"given":"Bidhan Chandra","family":"Bera","sequence":"first","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Manju","family":"Bernela","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aashwina","family":"Madhwal","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"},{"name":"Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly 243122, Uttar Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stephanie S.","family":"Pradhan","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"},{"name":"Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly 243122, Uttar Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Venkataramireddy","family":"Balena","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"},{"name":"Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly 243122, Uttar Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Taruna","family":"Anand","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Supriya","family":"Kandasamy","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"},{"name":"Division of Pathology, ICAR-Indian Veterinary Research Institute, Bareilly 243122, Uttar Pradesh, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Selvaraj","family":"Pavulraj","sequence":"additional","affiliation":[{"name":"Department of Pathobiological Sciences, School of Veterinary Medicine, Louisiana State University, Baton Rouge, LA 70803, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Wandit","family":"Ahlawat","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diksha","family":"Kandpal","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Priya","family":"Mor","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gurmesh","family":"Bishnoi","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nishant","family":"Vasdev","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bhupendra Nath","family":"Tripathi","sequence":"additional","affiliation":[{"name":"Indian Council of Agricultural Research, Krishi Bhawan, New Delhi 110012, Delhi, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4502-1852","authenticated-orcid":false,"given":"Tarun Kumar","family":"Bhattacharya","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5575-3307","authenticated-orcid":false,"given":"Nitin","family":"Virmani","sequence":"additional","affiliation":[{"name":"ICAR-National Research Centre on Equines, Sirsa Road, Hisar 125001, Haryana, India"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"37","DOI":"10.1111\/irv.12349","article-title":"Epidemiological and Virological Findings d9 Multiple Outbreaks of Equine Influenza in South America in 2012","volume":"10","author":"Perglione","year":"2016","journal-title":"Influenza Other Respir. 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