Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2026 Mar 14;208(5):252.
doi: 10.1007/s00203-026-04792-y.

LAW_RS03650: a species-specific novel antigen of Lawsonia intracellularis revealed via pangenomic reverse vaccinology method and serologically validated

Xuanwei Yin  1 , Xinglong Yu  2 , Chenyue Yan  1 , Yuezheng Xiao  3 , Yue Shen  1 , Yanlin Wang  4 , Wenyun Zheng  5 , Xingyuan Ma  6
Affiliations

LAW_RS03650: a species-specific novel antigen of Lawsonia intracellularis revealed via pangenomic reverse vaccinology method and serologically validated

Xuanwei Yin et al. Arch Microbiol. .

Abstract

Lawsonia Intracellularis (L. intracellularis) is an obligate intracellular bacterium that causes porcine proliferative enteropathy. In this study, a pan-RV (reverse vaccinology based on pangenome analysis) approach was applied to analyze the whole-genome sequences of 9 L. intracellularis strains downloaded from the National Center of Biotechnology Information (NCBI) server. Pangenome analysis revealed a closed pangenome and a core genome consisting of 1372 genes, while reverse vaccinology further revealed 16 candidate proteins with higher in silico immunogenicity parameters, including predicted antigenicity, "outer membrane protein" or "extracellular protein" by subcellular localization analysis and no more than 2 transmembrane regions by transmembrane helices prediction. Three of the 16 proteins that showed no homology with proteins of other species according to BLAST (Basic Local Alignment Search Tool) were selected for serological validation. The Western blotting results revealed that the 3 proteins did not cross-react with anti-Shigella and anti-Salmonella sera, with 1 protein (LAW_RS03650) showed antigenicity when it reacted with positive wild-type anti-L. intracellularis serum. The immunofluorescence of infected cells employing anti-LAW_RS03650 serum indicated a wide distribution of LAW_RS03650 protein in the host cells and L. intracellularis itself. This study identified a novel L. intracellularis antigen, LAW_RS03650, as a candidate for future recombinant vaccine development or species-specific serodiagnostic reagents.

Keywords: L. intracellularis; antigenic protein; pangenome analysis; reverse vaccinology; serology validation.

PubMed Disclaimer

Conflict of interest statement

Declarations. Conflict of interests: The authors declare no competing interests. Ethical approval: This study complied with the ARRIVE guidelines and the NIH Guide for the Care and Use of Laboratory Animals, following approval by the Biomedical Research Ethics Committee of Hunan Agricultural University and the Animal Ethics Committee of ProMab Biotechnologies Inc (Ethics ID-202510151553000586919). The sex of the animals is indicated in the methods section.

References

    1. Argemi X et al (2018) Comparative genomic analysis of Staphylococcus lugdunensis shows a closed pan-genome and multiple barriers to horizontal gene transfer. BMC Genomics. https://doi.org/10.1186/s12864-018-4978-1 - DOI - PubMed - PMC
    1. Arnold M, Crienen A, Swam H, von Berg S, Jolie R, Nathues H (2019) Prevalence of Lawsonia intracellularis in pig herds in different European countries. Porcine Health Manage. https://doi.org/10.1186/s40813-019-0137-6 - DOI
    1. Aves KL et al (2025) Outer membrane proteins as vaccine targets against lawsonia intracellularis in piglets. Vaccines https://doi.org/10.3390/vaccines13020207
    1. Baldasso DZ et al (2023) Development and validation of a flow cytometry antibody test for Lawsonia intracellularis. Front Immunol. https://doi.org/10.3389/fimmu.2023.1145072 - DOI - PubMed - PMC
    1. Bin P et al (2018) Intestinal microbiota mediates Enterotoxigenic Escherichia coli-induced diarrhea in piglets. BMC Vet Res. https://doi.org/10.1186/s12917-018-1704-9 - DOI - PubMed - PMC

MeSH terms