A group of investigators at the University of Georgia requests funds for a Balzers high pressure freezer to take advantage of the unique opportunities provided by this instrument in addressing a variety of relevant biological problems. The group has extensive prior experience with freeze substitution under standard conditions, plus preliminary data showing the efficacy of high pressure freezing in their systems. The freezer will support a wide range of research projects, e.g. host-pathogen interactions (Hussey, Fuller and Mims), desiccation acclimation in algae (Lingle), cytoskeletal organization during plant cell development and differentiation (Palevitz), extracellular space in frog retina (Karwoski) and ultrastructure of protozoal pathogens (Paulin). The projects entail examination of thin sections as well as additional applications such as electron immunocytochemistry. Our combined requirements of excellent ultrastructural preservation, retention of soluble components and antigenicity, and elimination of artifacts due to the slow action of fixatives under aqueous conditions or ice crystal formation in thick specimens require high pressure freeing followed by freeze substitution. The University of Georgia is committed to fostering ultrastructural research on campus and is prepared to provide 50% of the cost of the high pressure freezer.
