Abstract
Antibiotic resistance, bioterrorism and microbial induced autoimmune disorders have made bacterial infections a growing concern in our society. To confront these challenges, numerous studies over the past decade have focused on improving our understanding of the early immune response against microbial pathogens. Results from these investigations have demonstrated that the mammalian host recognizes infectious organisms through pattern recognition receptors (PRRs) that subsequently activate signal transduction pathways leading to gene transactivation. Global gene expression analyses have revealed that PRRs induce a large number of different immunomodulatory genes that can be divided into gene programs; sets of genes involved in initiating specific immunological functions. This review will focus on the Toll-like receptor (TLR) family of PRRs with respect to microbial recognition, signaling specificity and regulation of selected gene programs. Furthermore, the ability of bacterially expressed virulence factors to interfere with TLR-mediated responses will be addressed.
Keywords: autoimmune disorders, immunomodulatory genes, bioterrorism, pattern recognition receptors (PRRs)