TWENTY-FOURTH ANNUAL EASTERN FISH HEALTH WORKSHOP Royal Pavilion Resort, Atlantic Beach, NC MARCH 9-11, 1999 Fish Antibody Structural Diversity: Implications For Isotype-Like Functional Diversity Steven L. Kaattari1, J. V. Klemer1, and D. A. Evans2 1Dept. of Environmental Sciences, School of Marine Science, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062; 2Dept. of Physical Sciences, School of Marine Science, Virginia Institute of Marine Science, College of William and Mary, Gloucester Point, VA 23062 Teleost fish are generally thought to possess only one Ig isotype, a tetrameric IgM. We and other investigators have noted that this IgM molecule is not uniformly polymerized as are mammalian IgMs. Thus, the end product is a structurally and, perhaps, functionally diverse population of IgM molecules, derived from a single CH gene. Evidence also suggests that the molecule may be polymerized in a random process late in the secretory pathway, perhaps the secretory vesicle, as opposed to the ER. The existence of this assembly process may be important for the generation of antibody functional diversity and offer an alternate route for mediating antibody effector function rather than reliance on CH gene-encoded isotypic diversity. Return to 24th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page