The immune systems of various teleost fish have been studied in some detail for
the past several decades. One aspect of fish immunity, that of endogenously produced
modulating factors, has recently received a great deal of attention. Understanding the
functions and roles of endogenous factors that regulate fish immunity is paramount to
expanding the fields of fish immunology and vaccinology. It is know that several
lymphoid cell derived factors are detectable in in vitro cell culture systems and exhibit
immune modulating effects similar to well studied proteins in mammals. However in
comparison, few genes or gene products involved in the modulation of the trout immune
responses have been isolated, cloned and characterized.
The studies described herein were designed to isolate specific genes from rainbow
trout (0ncorhynchus mykiss) and characterize their involvement in the modulation and
regulation of the trout immune system. Two distinct genes were isolated cloned and
sequenced. The first, non-specific cytotoxic cell enhancement factor (NCEF) gene is
closely related to a human gene termed "natural killer enhancement factor" (NKEF) which
is important in the modulation of human natural killer cell activity. The second gene is
closely related to a group of recently characterized mammalian genes involved in the signal
transduction of cytokines termed "STATs". The role of these genes and their respective
protein products will be examined and discussed.
The antigenic structures of the fish proteins (NCEF and STAT5) were examined
by western blot and immunohistochemistry. Monoclonal antibodies derived against the
respective human proteins were found to cross react with the corresponding trout proteins,
demonstrating antigenic relatedness. The monoclonal regents were also used to analyze
the expression of these proteins in fish cells of lymphoid and non lymphoid origin.
In vitro cell culture analysis was used to determine the effects and roles of NCEF
and STAT5 gene products in the trout immune system. The cytolytic and apoptotic killing
activities of spleen, head kidney and peripheral blood leukocytes were found to be
enhanced by NCEF. Mitogenic stimulation of peripheral blood lymphoid cells resulted in
the trout STAT5 protein binding to a know sequences contained with in the promoters of
genes transcriptionally activated in response to cytokine exposure. / Graduation date: 1996
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/34620 |
| Date | 20 March 1996 |
| Creators | Mourich, Dan V. |
| Contributors | Leong, JoAnn C. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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