Wałecka-Zacharska E, Kosek-Paszkowska K, Bania J, Staroniewicz Z, Bednarski M, Wieliczko A
Pol J Vet Sci. 2015;18(4):697-702. doi: 10.1515/pjvs-2015-0090.
Animals are important reservoir of Listeria monocytogenes, a pathogen causing serious infections in both humans and livestock. However, data on invasiveness of L. monocytogenes strains of animal origin is very scarce. Ability of 18 L. monocytogenes strains of animal origin to invade HT-29 cells was investigated. Plaque forming assay was used to assess invasiveness and ability of the pathogen to spread in the cell line. Almost 40% of L. monocytogenes strains were weakly invasive. It was shown that strains from serogroup 4b exhibited the highest invasiveness, whereas serogroup 1/2b consisted of strains of invasiveness below 0.0001%. Analysis of translated inlA and inlB gene sequences revealed no premature stop codons. Lineage-specific mutations in low invasive strains were identified within inlA and inlB sequences. Our results demonstrate high incidence of low invasive animal L. monocytogenes strains, which may be at least partly explained by unique point mutations in the InlA and InlB.
动物是单核细胞增生李斯特菌的重要宿主，该病原体可在人类和牲畜中引发严重感染。然而，关于动物源单核细胞增生李斯特菌菌株侵袭性的数据非常稀少。本研究调查了18株动物源单核细胞增生李斯特菌侵袭HT-29细胞的能力。采用噬斑形成试验评估病原体在细胞系中的侵袭性和传播能力。近40%的单核细胞增生李斯特菌菌株侵袭性较弱。结果表明，4b血清型菌株的侵袭性最高，而1/2b血清型菌株的侵袭性低于0.0001%。对inlA和inlB基因序列的翻译分析未发现提前终止密码子。在低侵袭性菌株的inlA和inlB序列中鉴定出谱系特异性突变。我们的结果表明，低侵袭性动物源单核细胞增生李斯特菌菌株的发生率很高，这可能至少部分归因于InlA和InlB中的独特点突变。
