Genomewide characterization of host pathogen interactions by transcriptomic approaches Molekularbiologie Transkriptomanalyse In vivo In vitro Wirt Erreger Wechselwirkungen chronischer psychischer Streß Infektion Staphylococcus aureus sigB host pathogen interactions chronic psychological stress This thesis contains results from transcriptome studies on different aspects of host pathogen interactions. First liver gene expression profiles from a murine chronic stress model served to elucidate aspects of the influence of stress on metabolism and immune response state. Chronic stress in female BALB c mice was shown to lead to a hypermetabolic syndrome including induction of gluconeogenesis hypercholesteremia and loss of essential amino acids to the induction of the acute phase response but also of immune suppressive pathways and to the repression of hepatic antigen presentation. Increased leukocyte trafficking increased oxidative stress together with counter regulatory gene expression changes and an induction of apoptosis were detected. The influence of intra venous infection on the host kidney gene expression was analyzed in another murine model using the wild type strain Staphylococcus aureus RN1HG and its isogenic sigB mutant. Gene expression profiling indicated a highly reproducible host kidney response to infection. The comparison of infected with non infected samples revealed a strong inflammatory reaction of kidney tissue e. g. Toll like receptor signaling complement system antigen presentation interferon and IL 6 signaling ...