Immunology of Infectious Disease Commons^™

Macrophage Heterogeneity And Function In The Lung, Xin Li

Dartmouth College Ph.D Dissertations

Macrophages are critical custodians of the lung, orchestrating immune surveillance, maintaining tissue homeostasis, and coordinating both innate and adaptive responses. This dissertation examines their heterogeneity and specialized functions, focusing on IMs, which reside in the lung interstitium, and AMs, which occupy the airspace. Through comprehensive single-cell transcriptomic profiling of murine and human samples, we identify multiple IM and AM subsets defined by distinct chemokine, cytokine, receptor, and innate immune gene signatures. These subsets display clear divisions of labor, contributing to immune cell recruitment, tertiary lymphoid structure formation, and alveolar homeostasis.

In IMs, coordinated chemokine programs not only recruit inflammatory cells …

Neutrophil Inflammatory Death Regulation By Bacterial Type Iii Secreted Effectors, Arianna D. Reuven

Dartmouth College Ph.D Dissertations

Yersinia and Pseudomonas use a T3SS to secrete effectors into host cells that inhibit phagocytosis and modulate immune responses, such as inflammasome activation. Inflammasomes promote the activation of the proinflammatory protease caspase-1. The activation of an inflammasome sensor in response to a signal or ligand initiates the assembly of the inflammasome leading to activation of caspase-1 which cleaves GSDMD and pro-inflammatory cytokines IL-1β and IL-18 into their mature forms. As neutrophils are recruited in large quantities to sites of infection, they are excellent candidates to drive inflammasome dependent responses. Neutrophils have been shown to produce multiple inflammasomes, like pyrin and …

Sounding The Alarm: Local Cues That Drive Functional Specialization Of Brain Resident Memory T Cells, Shawn Christopher Musial Jr.

Dartmouth College Ph.D Dissertations

Resident memory T cells are a unique subset of memory T cells that persist within tissues throughout the body, including the brain, optimally positioned to exert local immune activation. Broadly, T cells in the CNS are implicated in a range of neurologic disorders, can protect against reinfection, and even participate in normal CNS homeostasis. Despite this, there remain significant gaps in knowledge about how T cells, specifically resident memory T cells (T_RM), are regulated and function in the unique CNS environment. Here, we leverage a mouse model of acute viral infection to dissect the diversity of brain T …

The Immune Modulation On Innate Immunity, From Pathogen Recognition To Fungal Clearance., Ko-Wei Liu

Dartmouth College Ph.D Dissertations

The human lung is not sterile but a complex environment with various microorganisms. Besides commensals in the lung, hundreds to thousands of individual microbiomes enter the lung every day but without causing the symptom. Host innate immunity plays an important role in maintaining homeostasis of the lung environment and as the first defense line against pathogens. Aspergillus fumigatus (A. fumigatus) is a saprophytic filamentous fungus that can cause human disease in immune compromised patients. However, with functional innate immunity, immune cells can quickly recognize pathogen associated molecular patterns (PAMPs) from A. fumigatus through pattern recognition receptors (PRRs). The activation of …

Response And Molecular Control Of Cd8 T Cells During Infection And Cancer, Nicholas K. Preiss Dr.

Dartmouth College Ph.D Dissertations

CD8 T cells are potent immune effector cells capable of vast clonal expansion and clearance of infected or cancerous cells. After control of the pathogenic insult, CD8 T cells develop into quiescent, long-lived memory populations that are poised to mediate rapid protection upon reencounter with cognate antigen. These properties make control of CD8 T cell responses a highly desirable outcome of vaccine strategies and immunotherapy. Therefore, understanding how the effector function and memory differentiation of CD8 T cells are controlled at a molecular level is of great importance. In the context of infection with gammaherpesviruses (γHV), which form a latent …