Date Thesis Awarded


Access Type

Honors Thesis -- Access Restricted On-Campus Only

Degree Name

Bachelors of Science (BS)




Patty Zwollo

Committee Members

Mark H. Forsyth

Matthew J. Wawersik

Louis Rossiter


Rainbow trout are farmed worldwide as a popular food source, and represent a critical stage in the evolutionary history of the immune system. Teleosts lack bone marrow, the site of hematopoiesis in mammals. Instead, the anterior kidney of many fish species has been described as the site of early B cell development. This project sought to expand on a previously published model of the B cell populations in trout immune tissues using flow cytometry analysis of the kidney. The model suggests that a maturation gradient exists along the trout kidney, with the earliest B cell precursors in the anterior kidney, and mature B cells residing in the posterior kidney. If the maturation gradient exists, this project hypothesized that detecting B cell populations in the kidney would reveal an inverse relationship between precursor and mature B cell populations along the kidney gradient. Cell size, cell complexity, and antibodies which detect the transcription factors EBF, Pax5, and Xbp-1, as well as anti-IgM and RAG-1 antibodies were used to define precursor and mature B cell populations throughout the kidney of small and large trout. This project confirmed an inverse relationship between the precursor and mature B cell populations along the kidney gradient in large fish, with specialization of the anterior kidney for early B cell development, and the posterior kidney containing many resting mature B cells. Differences were also discovered between large and small fish mature B cell populations and Xbp-1 expression.

Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.


Thesis is part of Honors ETD pilot project, 2008-2013. Migrated from Dspace in 2016.

On-Campus Access Only