Dr. Chitko-McKown is a veterinary immunologist whose research focuses on understanding how the innate immune response of food animal species responds to infectious agents.  To investigate the host-pathogen interactions, projects are designed using techniques ranging from classical cellular assays to analyses at the genomic level.  One ongoing project involves the identification of genetic variation in cattle populations within the bovine NOS2A gene and the relationship between nucleotide polymorphisms and bactericidal activity in monocyte-derived macrophages - a cell type that forms the first line of defense against numerous pathogens.  An additional area of study is the response of bovine macrophages upon exposure to pathogens.  Using microarray technology, we have identified alterations in the expression of over 40 genes due to exposure to E. coli O157:H7 lipopolysaccharide; 15 of these genes had never been described in cattle.  Results from these experiments will help direct us to promising areas of intervention or prevention of infectious diseases by allowing the selection of more resistant animals in breeding programs or by identifying target genes or pathways that may be conducive to pharmacological treatment.