Life Sciences Commons^™

Aging Effects On Acute Lung Inflammation After Burn Injury, Vanessa Nomellini

Dissertations

The risk of complications and death after a moderate sized burn injury is significantly higher in persons over the age of 65, while almost non-existant in young, healthy individuals. The studies outlined below use a murine model to determine the mechanisms behind the development of pulmonary complications that frequently occur in aged individuals following burn injury. We hypothesized that, since aged mice maintain an elevated proinflammatory state prior to injury, they are at an even greater risk of pulmonary inflammation than young mice given a comparable sized wound. We found that neutrophils continue to accumulate in the lungs of aged …

Ethanol Impairs Mechanisms Of Macrophage Phagocytosis And Cytokine Production, John Karavitis

Dissertations

Extensive evidence indicates that alcohol (ethanol) consumption affects human health by altering normal physiological functions of the immune system. This study investigated the effect of a single in vivo exposure of macrophages to clinically relevant levels of ethanol (1.2 and 2.2 g/kg). Following 3 hour exposure, both doses of ethanol decreased ex vivo TNFα production by splenic and alveolar macrophages (AMs). Interestingly, the higher dose of ethanol resulted in sustained suppression of LPS-induced TNFα production at 3 and 6 hours post ethanol administration, as well as decreased IL-6 and IL-12 production after 6 hours, compared control treated groups. LPS or …

Functional And Phenotypical Analysis Of The Effects Of Aging On B Cells And Their Bone Marrow Microenvironment, Nicole May Ziegler

Master's Theses

Aging impacts multiple organ systems, and specifically causes the immune system to lose its ability to efficiently fight off infections. Regarding immunity, aging research predominantly focuses on the adaptive immune system. B cells, which mediate the humoral arm of the adaptive immune system, develop throughout life in the bone marrow where microenvironmental `niches' are important. The bone marrow does not exactly `atrophy' with age; however, studies comparing young and old mice demonstrate an age-related change in the bone marrow B cell subpopulations.

The overall goal was to determine if femoral and sternum bone marrow have different plasma cell composition and …

Phenotypical And Functional Analysis Of Peripheral T Cells In Foxn1 Transgenic Mice: Effects Of Aging, Paulette Krishack

Master's Theses

The thymus is the primary organ for the development and production of TCRαβ naive T cells. However, with increasing age thymic involution occurs, causing a decline in the output of naïve T cells. The decline in naïve T cell production results in a contraction in the peripheral naïve and expansion of the memory T cell pools. Not only are the production and compositions of peripheral T cells altered with age, T cell functions such as T cell proliferation and production of cytokines required for cell proliferation are also declined. Currently, it is not known if restoring the decline in the …

Phospholipase D Signaling In T Cells, Uma Chandrasekaran

Dissertations

Antigen stimulation of T lymphocytes induces the activation of phospholipase D (PLD) signaling. Phospholipase D (PLD) is a phosphodiesterase that catalyzes the conversion of phosphatidyl choline (PC) to phosphatidic acid (PA). PA is an important lipid second messenger and is known to mediate a variety of cellular functions. However, the specific role of PA in T lymphocytes has not been established. Previous studies indicated differential requirement for TCR induced PLD signaling in regulatory and non-regulatory T cells. Inhibition of TCR induced PLD signal preferentially suppressed the growth of non-regulatory T cells while allowing the proliferation of regulatory T cells in …

B Lymphocyte Development In Galt, Venkata Arunachalam Yeramilli

Dissertations

In rabbits, the primary antibody repertoire is generated in the gut-associated lymphoid tissues (GALT), where bone marrow (BM)-derived B cells undergo a proliferative expansion and somatically diversify the immunoglobulin genes. Unlike in other species, B lymphopoiesis in rabbit arrests a few months after birth, and it is unclear how the peripheral B cell compartment is maintained when there is no influx of newly-made B cells from the BM.

For my dissertation, I investigated how B cells develop in the GALT of rabbits, and how they are maintained in adults after the arrest of lymphopoiesis. To identify cellular signals that promote …