Immunity Commons^™

Toxin-Like Proteins In The Venom Of Drosophila Parasitoids, Lady V. Cardenas

Dissertations and Theses

The figitid parasitoid wasps of Drosophila are gaining importance in agriculture due to their ability to kill the resilient soft-fruit pest Drosophila suzukii. Their success and infection strategies vary, and the mechanisms underlying these differences are largely unknown. Some of their venom proteins have been shown to be important in suppressing host defense. Here, we report that Ganaspis brasiliensis, a parasitoid of D. suzukii survives well on Drosophila yakuba, a host species with a strong cellular immunity, and infected flies are unable to mount a strong immune response. To predict possible toxin-like proteins in Ganaspis venoms that might suppress cellular …

Explorations Of Dna-Single-Walled Carbon Nanotube Interactions To Develop Multiplexed Molecularly Specific Biosensors For Inflammation, Amelia K. Ryan

Dissertations and Theses

Inflammatory cytokines such as interleukin-6 (IL-6) and interleukin-12 (IL-12) are central regulators of immune signaling and key biomarkers of disease, yet existing assays for their detection remain slow, invasive, and lack multiplexing ability. This dissertation advances the development of single-walled carbon nanotube (SWCNT) optical nanosensors capable of real-time, multiplexed, and molecularly specific cytokine detection through innovative use of single-stranded DNA (ssDNA) interfaces.

First, an IL-6-specific DNA aptamer was employed as both a dispersing agent and recognition probe for SWCNT fluorescence sensing. Sequence modifications, including anchor domains, truncations, and thermally induced refolding, were systematically tested to optimize sensitivity and selectivity. The …

Atm-/-Ung-/- Mice Present Reduced Levels Of Switched Immunoglobulin Isotypes Igg1 And Igg3, Lyric M. Haughton

Dissertations and Theses

B cells excise and recombine the immunoglobulin heavy chain gene locus during class switch recombination (CSR). CSR is mediated by activation induced cytidine deaminase (AID) and results in a new immunoglobulin isotype that B cells will secrete and present. AID produces mutations that convert cytosines to uracils within the intronic switch regions that precede and follow the target immunoglobulin isotype coding sequence. To resolve the mutations, B cells conduct either base excision repair (BER) or mismatch repair (MMR). Inactivating genetic mutations in BER or MMR reduce CSR. For example, a knock-out of uracil DNA glycosylase (UNG) causes a 50% reduction …

Molecular And Genetic Studies On A Sipd/Ipad-Related Virulence Spike Protein From Immune-Suppressive Particles Of A Drosophila Parasitoid, Carlo Miguel A. Sevilla

Dissertations and Theses

Parasitoid wasps are effective biological control agents that have evolved intricate host immune suppression strategies to overcome host immune defenses. The most important anti-parasite defense mechanism is encapsulation, where the host’s blood cells surround the wasp egg. In the Drosophila/Leptopilina host-parasitoid system, extracellular vesicles (EVs) are oviposited along with the wasp egg. The EVs possess spikes and contain hundreds of proteins, some of which enable wasp eggs to escape encapsulation by changing the morphology and function of hemocytes, or killing them. Previous studies have identified an abundant surface/spike protein (SSp40) from Leptopilina heterotoma EVs. While p40, a predicted …

Bone Marrow Derived Progenitor Cells And Their Contributions To The Thymic Stroma, Mohammed Hoque

Dissertations and Theses

The thymus serves as the primary lymphoid organ responsible for the development and selection of a self-tolerant T cell repertoire. In paradox to its critical functions for the adaptive immune response, the thymus undergoes a profound age associated decline beginning in early adult life resulting in significant decline in T-cell function.Thymic epithelial cells (TECs) are the most critical component of the thymic microenvironment and undergo rapid turn-over, so understanding the cellular mechanisms responsible for the maintenance of TEC number and organization will be critical in counteracting age associated involution, particularly in cancer patients, due to enhanced degeneration in response to …