Dr. Sundick's laboratory is primarily involved in characterizing the function of chicken interleukin-2, a gene they cloned recently. Their studies are directed toward the improvement of poultry husbandry by; 1. Characterizing the effects of IL-2 on avian T, B and NK cells, and 2. utilizing it as an adjuvant in avian vaccines. To these ends, a student in the lab, Jill Kolodsick, optimized a bacterial expression system for producing high yields of biologically active protein. This protein is being used both in their laboratory and elsewhere to determine its in vivo and in vitro effects on the chicken immune system. Other students, Drs. Wanping Hu and Yufang Yang, have been involved in developing a novel vaccine which consists of the IL-2 protein administered with viral protein. This vaccine formulation, and the genes encoding the two proteins inserted into plasmid vectors, are being tested for their protective effects in chickens against viral pathogens. These experimental chicken vaccines may have utility for both the commercial poultry industry and for the development of novel vaccines for human use.

To identify and characterize critical sites on chicken IL-2, Jill Kolodsick produced numerous mutants by PCR mutagenesis, and tested them for their biological effects on activated T cells. Mutants that were biologically inert were then tested for their ability to inhibit the effects of wild-type IL-2. Results obtained in these studies have increased our understanding of chicken IL-2 function and the function of both mammalian IL-2 and IL-15, two genes that developed from a common ancestral gene.

Having developed expertise in the cloning of chicken cytokine genes by expression library screening, Dr. Sundick's laboratory applied this expertise toward the cloning of fish cytokines and chemokines. To this end they optimized in vitro culture conditions for the maintenance and activation of rainbow trout T cells. Then they isolated mRNA from the activated cells, reverse transcribed it into cDNA and constructed a cDNA library in a eukaryotic expression vector. The library was enriched for cytokine and chemokine genes. Sequencing of random clones resulted in the isolation of a novel trout chemokine. Studies are underway to determine the utility of this chemokine as a vaccine adjuvant.