Immunity Commons^™

Ecoimmunology Of Dirty Physella Acuta Snails, Kevin Arthur Mcquirk

Biology ETDs

Research on Physella acuta, an invasive freshwater snail, reveals insights into its parasitology, fitness, and molecular biology. Morphological and molecular analyses revealed two distinct mitogenomic lineages, local (B) and invasive (A) strains of native P. acuta, both having comparable trematode infection rates, suggesting that the low infection rates observed from A in invaded regions result from "enemy release" rather than immune incompatibility. Fitness assessments showed that while lineages A and B performed similarly under laboratory conditions, rewilding experiments revealed significantly higher fitness in lineage A. Transcriptomic profiling supported these differences, with A snails showing greater immune-related gene expression and …

Immune Regulation In Fungal Airway Inflammation And Host Defense, Ruoning Wang

Biomedical Sciences ETDs

Asthma is a chronic inflammatory disease of the lungs characterized by complex pathophysiological mechanisms and diverse endotypes, primarily categorized as T helper type 2 cell (Th2)-high and Th2-low asthma. Despite significant advances in understanding asthma pathogenesis, the mechanisms governing the pulmonary immune system’s response to external challenges have not been fully understood. To address these gaps, this comprehensive project was designed to investigate the interplay between fungal infections and specific CD4⁺ T cell populations in asthma. Our findings suggest that fungal infections can contribute to neutrophilic asthma by promoting the migration of platelet-myeloid aggregates into the lungs. We also …

Host-Microbiome Interactions In The Teleost Brain, Amir Mani Varnoosfaderani

Biology ETDs

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 …

Mucosal Immune System Of African Lungfish, Ryan D. Heimroth

Biology ETDs

Conquering land was an apex moment in the evolution of vertebrates. Physiologically, the first vertebrates to transition to life on land had to adapt in order to survive in an oxygen-rich environment where gravitational forces and limited water prevailed. Several extant vertebrates including anurans and lungfish, survive droughts by undergoing aestivation. Unfavorable environmental conditions trigger lungfish to aestivate. Aestivation is a process of metabolic torpor wherein the fish will encase itself in a mucus cocoon and not move until favorable environmental conditions (food and water) are reintroduced. Aestivation can be reproduced in laboratory settings and, thus, lungfish can be used …

The Role Of Adaptive Immunity In Chronic Hypoxia-Induced Pulmonary Hypertension, Levi David Maston

Biomedical Sciences ETDs

Inflammation is a prominent pathologic feature in pulmonary arterial hypertension as demonstrated by pulmonary vascular infiltration of inflammatory cells, including T and B lymphocytes. However, the contribution of the adaptive immune system is not well characterized in pulmonary hypertension (PH) caused by chronic hypoxia (CH). Inflammatory cells, through various mechanisms, have the capability to increase pulmonary vascular resistance in various disease states. CD4⁺T cells have the potential to play a significant role in the disease process initiated by hypoxia. CD4⁺T cells are largely responsible for orchestrating downstream immune processes and are critical in focusing and amplifying …

Determining Mediators Of Naive T Cell Motility And Dc Association In The Lymph Node, Janie Rae Byrum

Biomedical Sciences ETDs

To become activated and perform effector functions, naive T cells move within lymph nodes to scan dendritic cells presenting antigen. Previous work has shown naive T cell activation is promoted by interleukin 7 in vivo, and it does so by regulating the T cell:dendritic cell interaction. Our work identifies a novel role for IL-7 in mediating naive T cell motility in the lymph node and promoting T cell association with DCs. Additionally, we have developed a method for analyzing microscopy images, regionalized normalized mutual information, to assess intercellular associations between T cells and other cells within the lymph node. Dendritic …

Physella Acuta, Comparative Immunology And Evolutionary Aspects Of Gastropod Immune Function, Jonathan H. Schultz

Biology ETDs

Gastropod immunobiology has benefitted from investigations focused on the planorbid snail Biomphalaria glabrata, intermediate host for the human parasite Schistosoma mansoni. Though such concentrated efforts have elucidated fascinating aspects of invertebrate immunity, they have not provided full knowledge regarding the evolution of immune function among other gastropod species. This dissertation presents the importance of making strategic choices regarding which organisms to select for comparative immunology. Herein, the choice was made to investigate the immunobiology of Physella acuta, a freshwater snail species of the Physidae, a sister family to Planorbidae to which B. glabrata belongs. Benefiting greatly from …

From Olfaction To Immunity: Characterization Of Nasal Immunity In Bony Fish, Ali Sepahi

Biology ETDs

The olfactory system is a common route pathogen entry in vertebrates. As a consequence, the nasopharynx-associated lymphoid tissue (NALT) needs to rapidly clear infections without compromising the sense of olfaction. NALT is present in teleost fish but its cellular and molecular mechanisms of action have not been investigated to this date. This dissertation focuses on three aims: 1. investigating the role of CCL19-like as a primordial chemokine in vertebrate nasal immunity, 2. determining the presence of tissue microenvironments within the olfactory organ (OO) of rainbow trout, and 3. understanding the immune contributions of olfactory sensory neurons (OSNs) in teleosts against …

Regulations Of Pathogenic Cd4+ T Helper Lymphocytes In Inflammatory Diseases, Handong Zheng

Biomedical Sciences ETDs

In this comprehensive project, three interrelated studies with distinct foci were employed to understand the regulations of specific CD4⁺ T helper cell population in inflammatory diseases.

Pathogenic TH17 cells play an essential role in the initiation and development of both human multiple sclerosis (MS) and animal experimental autoimmune encephalomyelitis (EAE). Nevertheless, the underlying mechanism by which the pathogenicity of TH17 cells is controlled in the autoimmune neuro-inflammation remains unclear. In aim 1, we revealed that lumican (Lum), an extracellular matrix (ECM) protein, negatively regulates encephalitic TH17 cell responses. Our findings highlighted a TH17 cell-intrinsic effect of Lum in suppressing …