title: Burkholderia pseudomallei Rapidly Infects the Brain Stem and Spinal Cord via the Trigeminal Nerve after Intranasal Inoculation.
abstract: Infection with Burkholderia pseudomallei causes melioidosis, a disease with a high mortality rate (20% in Australia and 40% in Southeast Asia). Neurological melioidosis is particularly prevalent in northern Australian patients and involves brain stem infection, which can progress to the spinal cord; however, the route by which the bacteria invade the central nervous system (CNS) is unknown. We have previously demonstrated that B. pseudomallei can infect the olfactory and trigeminal nerves within the nasal cavity following intranasal inoculation. As the trigeminal nerve projects into the brain stem, we investigated whether the bacteria could continue along this nerve to penetrate the CNS. After intranasal inoculation of mice, B. pseudomallei caused low-level localized infection within the nasal cavity epithelium, prior to invasion of the trigeminal nerve in small numbers. B. pseudomallei rapidly invaded the trigeminal nerve and crossed the astrocytic barrier to enter the brain stem within 24 h and then rapidly progressed over 2,000 μm into the spinal cord. To rule out that the bacteria used a hematogenous route, we used a capsule-deficient mutant of B. pseudomallei that does not survive in the blood and found that it also entered the CNS via the trigeminal nerve. This suggests that the primary route of entry is via the nerves that innervate the nasal cavity. We found that actin-mediated motility could facilitate initial infection of the olfactory epithelium. Thus, we have demonstrated that B. pseudomallei can rapidly infect the brain and spinal cord via the trigeminal nerve branches that innervate the nasal cavity.
authors.affiliation: Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia.
authors.forename: James A
authors.initials: JA
authors.lastname: St John
authors.affiliation: Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia.
authors.forename: Heidi
authors.initials: H
authors.lastname: Walkden
authors.affiliation: Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia.
authors.forename: Lynn
authors.initials: L
authors.lastname: Nazareth
authors.affiliation: Institute for Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia.
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Beagley
authors.affiliation: School of Medical Science, Griffith University, Gold Coast, Queensland, Australia Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia.
authors.forename: Glen C
authors.identifier: 0000-0002-9638-8091
authors.initials: GC
authors.lastname: Ulett
authors.affiliation: Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Batzloff
authors.affiliation: Institute for Glycomics, Griffith University, Gold Coast, Queensland, Australia i.beacham@griffith.edu.au jekberg@bond.edu.au.
authors.forename: Ifor R
authors.initials: IR
authors.lastname: Beacham
authors.affiliation: Eskitis Institute for Drug Discovery, Griffith University, Brisbane, Queensland, Australia Faculty of Health Sciences and Medicine, Bond University, Gold Coast, Queensland, Australia Institute for Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Queensland, Australia i.beacham@griffith.edu.au jekberg@bond.edu.au.
authors.forename: Jenny A K
authors.initials: JA
authors.lastname: Ekberg
mesh_terms: D000281:Administration, Intranasal / Q000379:methods; D000818:Animals; D001933:Brain Stem / Q000382:microbiology*; D016957:Burkholderia pseudomallei / Q000472:pathogenicity*; D008554:Melioidosis / Q000382:microbiology; D051379:Mice; D009296:Nasal Cavity / Q000382:microbiology*; D013116:Spinal Cord / Q000382:microbiology*; D014276:Trigeminal Nerve / Q000382:microbiology*