Date of Award
5-30-2019
Document Type
Dissertation
Degree Name
Molecular Biosciences, Ph.D.
First Advisor
Maureen Dolan
Committee Members
Carole Cramer; Elizabeth Hood; Jianfeng Xu; Rebecca Lochmann
Call Number
LD 251 .A566d 2019 E46
Abstract
As the world population increases and wild caught fisheries decline, aquaculture offers an important sustainable solution addressing this global challenge. In fact, aquaculture now provides more than half the world’s food fish. With this rapid rise in production, has come the problem of disease management. Current options are limited and there is a great need for innovative solutions to this problem. The cytokine interleukin-22 (IL-22) has emerged as a therapeutic target for fish and is correlated with protection under pathogen challenge. Plant bioproduction has the potential to effectively manufacture recombinant IL-22 and offer advantages of low cost for commodity markets, ready scalability, and is environmentally friendly. Recombinant catfish IL-22 (cfIL-22) was expressed using the Agro-mediated transient tobacco production system and purified for establishing functional activity of this therapeutant to trigger the fish’s immune system. As IL-22 is known to induce production of natural antimicrobials and tissue repair proteins, it may provide an alternative to antibiotics or function as a disease preventative in aquaculture production. To assess activity of cfIL-22, in vitro bioassays using a catfish ovary cultured cell line were established. The cell proliferation assay and gene expression analysis that detected a suite of antimicrobial and tissue repair genes strongly support that the plant-made cfIL-22 protein is functional. The recombinant cfIL-22 was also tested in vivo in catfish fingerlings. This preliminary study of treated and untreated fish, which evaluated gene expression of key marker genes in gill and liver tissues and histology of gut tissue further validated recombinant cfIL-22 activity. Additional tools including an antibody were developed along with establishing other bioassay platforms (e.g. antimicrobial assay, wounding assay) that have utility in validating IL-22 activity as well as assessing other novel immune biologics in fish. If successful, this recombinant protein therapeutant may offer economic benefits to the aquaculture industry in providing a safer therapy with less/no negative impact on the environment and a better regulatory and consumer acceptance of antibiotic-free farm fish products.
Rights Management
This work is licensed under a Creative Commons Attribution 4.0 International License.
Recommended Citation
Elkins, Lana, "Recombinant Production of Catfish Interleukin-22 As A Natural Immune Stimulant for Improving Aquaculture Fish Health" (2019). Student Theses and Dissertations. 454.
https://arch.astate.edu/all-etd/454
