{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T15:01:00Z","timestamp":1772550060406,"version":"3.50.1"},"reference-count":123,"publisher":"Microbiology Society","issue":"2","license":[{"start":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T00:00:00Z","timestamp":1772064000000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2026,2,26]]},"abstract":"<jats:p>\n                    Exposure to microbes is essential to promote the development of the host\u2019s immune system. Commensal microbes (i.e. the microbiota) which are acquired early in life play a vital role in immune priming. Whilst many organisms within the microbiota are harmless, some can be considered opportunistic pathogens. Examples include\n                    <jats:italic>Staphylococcus aureus<\/jats:italic>\n                    ,\n                    <jats:italic>Streptococcus pneumoniae<\/jats:italic>\n                    and\n                    <jats:italic>Pseudomonas aeruginosa<\/jats:italic>\n                    , and these organisms can also contribute to the development of a healthy host immune system. At the extreme end of the spectrum, pathogens which typically do not form part of the microbiota (e.g.\n                    <jats:italic>Mycobacterium tuberculosis<\/jats:italic>\n                    ,\n                    <jats:italic>Bordetella pertussis<\/jats:italic>\n                    and\n                    <jats:italic>Salmonella<\/jats:italic>\n                    Typhimurium) have been shown to provide cross-protection against infectious and non-infectious diseases in mice. Attenuated strains of these pathogens, such as BPZE1, could have clinical applications, whilst Bacillus Calmette\u2013Gu\u00e9rin, a live-attenuated\n                    <jats:italic>Mycobacterium bovis<\/jats:italic>\n                    strain, has been shown to have non-specific effects against cancers and other diseases. A wide range of organisms, from harmless microbiota to potentially life-threatening infections, interact with the host immune system and can prime or modulate the immune response in different ways. In this review, we discuss the important role that pathogens, including opportunistic components of the microbiota, play in the development and maintenance of host immunity to a wide range of infectious and non-infectious diseases.\n                  <\/jats:p>","DOI":"10.1099\/mic.0.001680","type":"journal-article","created":{"date-parts":[[2026,2,26]],"date-time":"2026-02-26T17:15:41Z","timestamp":1772126141000},"source":"Crossref","is-referenced-by-count":0,"title":["Pathogens as commensals: microbial priming of the immune system and heterologous protection"],"prefix":"10.1099","volume":"172","author":[{"given":"Thomas","family":"Belcher","sequence":"first","affiliation":[{"name":"School of Life Sciences, Keele University, Keele, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5299-4401","authenticated-orcid":false,"given":"Emily J.","family":"Stevens","sequence":"additional","affiliation":[{"name":"School of Life Sciences, Keele 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:\/\/www.microbiologyresearch.org\/content\/journal\/micro\/10.1099\/mic.0.001680?crawler=true&mimetype=application\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T11:17:02Z","timestamp":1772536622000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.microbiologyresearch.org\/content\/journal\/micro\/10.1099\/mic.0.001680"}},"subtitle":["&lt;xhtml:span xmlns:xhtml=\"http:\/\/www.w3.org\/1999\/xhtml\" xml:lang=\"en\"&gt;&lt;p&gt;This article is part of our &lt;span style=\"color: rgb(33, 51, 104);\"&gt;&lt;a href=\"\/content\/emerging-investigators-collection-2025-26\"&gt;Emerging Investigators collection&lt;\/a&gt;&lt;\/span&gt;.&lt;\/p&gt;&lt;p style=\"line-height: 1.2;\"&gt;&lt;img src=\"\/upload\/emerging\/Emily_Stevens.png\" alt=\"photograph of Emily Stevens\" class=\"ImageBorder img-responsive eb-people fr-fic fr-dib\" style=\"width: 120px; float: left; margin: 0 10px 10px 0;\" \/&gt;&lt;span style=\"font-size: 12px; font-weight: normal;\"&gt;&lt;strong&gt;Emily Stevens&lt;\/strong&gt; completed their undergraduate degree in Biology at the University of Bath in 2015, before completing their PhD in Microbiology at the University of Bristol in 2019. They worked as a post-doctoral researcher at the University of Oxford until taking up a lectureship position in Microbiology and Immunology at Keele University in 2024. Their research focuses on bacterial pathogenesis and evolution. In particular, they are interested in the evolution of bacterial opportunistic pathogens, with a focus on understanding how these organisms transition from harmless commensals to harmful pathogens. They are also interested in the interactions between opportunistic pathogens and host microbiota, and in the role of microbiota components in protecting against the onset of infectious disease.&amp;#160;&lt;\/span&gt;&lt;\/p&gt;\n&lt;\/xhtml:span&gt;"],"short-title":[],"issued":{"date-parts":[[2026,2,26]]},"references-count":123,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2026,2,26]]}},"URL":"https:\/\/doi.org\/10.1099\/mic.0.001680","relation":{},"ISSN":["1350-0872","1465-2080"],"issn-type":[{"value":"1350-0872","type":"print"},{"value":"1465-2080","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,2,26]]}}}