Date of Graduation

Summer 2015

Document Type

Honors Research Project

Degree Name

Bachelor of Science



Research Sponsor

Dr. James Holda

First Reader

Dr. Jordan Renna

Second Reader

Dr. Donald Ott


Chronic inflammation can result in pathophysiological changes to numerous organs of the body such as heart tissue (atherosclerosis) and damage to bone. Sources of inflammation can include autoimmune disease, cancer, and chronic infections such as those triggered by HIV or Mycobacterium tuberculosis. Most of the damage associated with chronic inflammation can be associated with chemical mediators, cytokines, given off by cells of the innate immune system. One measure of an active innate immune system can be assessed by quantifying nitric oxide (NO) production by bone marrow (BM) cells.

The purpose of these experiments is to determine if zymosan, a known inflammatory molecule associated with yeast cell wall, could stimulate cells of the innate immune response to produce cytokines capable of inducing NO production by BM cells. In these experiments mouse spleen cells were used as a source of innate immune cells and BM cells as the NO producing cell. In vitro, SpC and BM were cultured with yeast and NO production measured by the Greiss assay. In vivo mice were injected with yeast in the footpad and 48 hours later BM was removed and cultured and tested for NO production.

In vitro and in vivo experiments show that yeast could stimulate cells of the innate immune system to produce cytokines that could activate NO production. The levels NO produced were low but significant. The results show that yeast can activate cells of the innate immune system and potentially be a source of chronic inflammation.