Date of Award


Level of Access Assigned by Author

Campus-Only Thesis

Degree Name

Master of Science (MS)




Carol H. Kim

Second Committee Member

Paul J. Millard

Third Committee Member

Mary E. Rumpho


The impact of environmental toxicants on innate immunity was the focus of this thesis. The innate immune response constitutes the first line of defense against invading pathogens and consists of a variety of immune defense mechanisms. The focus of this work concentrates on arsenic, which is an environmental contaminant that causes many health issues in the state of Maine. The zebrafish is widely used as a model system for biomedical research because of its rapid rate of reproduction, the optical clarity of its embryos, and the wealth of genetic information that is available. To study the effects of arsenic on the zebrafish, a bioassay that provides biological relevance to cytokine expression data had to be developed. To this end, an assay that measures the respiratory burst of phagocytes was developed as a reliable measure of the immune response of a host. Numerous assays have been developed to measure this response in a variety of mammal and fish species, however, no respiratory burst assay has been available for the zebrafish. The first part of this thesis describes the development of a respiratory burst assay for the zebrafish, which is especially difficult because of the small size of the zebrafish. The second part of this thesis, examines the effects of arsenic on the innate immune response of zebrafish embryos. The respiratory burst response upon arsenic exposure is examined with the newly developed assay. Other effects of arsenic, such as baseline cytokine expression and induction of cytokines upon viral infection are examined as well.