Biology ETDs

Publication Date

Summer 7-17-2024

Abstract

This dissertation investigates host-microbial interactions within the teleost brain, previously considered sterile. Reviewing current literature highlights significant gaps in understanding teleost brain immunity, despite prevalent neurotropic diseases. We mapped the immune profiles of rainbow trout brains and meninges, revealing the olfactory bulbs as the immune effector part of the brain and the optic tectum as a nod2 expression hub. High il6 and il10 levels were noted in the telencephalon. A persistent bacterial community within healthy salmonid brains shares diversity with gut and blood microbiota. Brain bacterial isolates exhibit genomic signatures for brain colonization and polyamine biosynthesis. The microbiota shifts across the host's life cycle, becoming dysbiotic in mature Chinook salmon. Translocated microbiota induce sickness behaviors in trout, with il1b and tnfa expression in the telencephalon uncoupled from il6 during systemic inflammation. Polyamine metabolism alterations are telencephalon specific. Disrupting bacterial polyamine metabolism prevents behavioral fever and inflammation, highlighting polyamines' role in neurobehavioral responses to systemic insults.

Project Sponsors

National Science Foundation

Language

English

Keywords

Brain microbiome, CNS immune responses, Behavioral fever, Polyamines, Gut-brain axis, Neuroimmunology

Document Type

Dissertation

Degree Name

Biology

Level of Degree

Doctoral

Department Name

UNM Biology Department

First Committee Member (Chair)

Dr. Irene Salinas

Second Committee Member

Dr. Erin Milligan

Third Committee Member

Dr. Vincent Martinson

Fourth Committee Member

Dr. Marlies Meisel

Download

Share

COinS