title: Unique gene expression profiles of human macrophages and dendritic cells to phylogenetically distinct parasites.
abstract: Monocyte-derived dendritic cells (DCs) and macrophages (Ms) generated in vitro from the same individual blood donors were exposed to 5 different pathogens, and gene expression profiles were assessed by microarray analysis. Responses to Mycobacterium tuberculosis and to phylogenetically distinct protozoan (Leishmania major, Leishmania donovani, Toxoplasma gondii) and helminth (Brugia malayi) parasites were examined, each of which produces chronic infections in humans yet vary considerably in the nature of the immune responses they trigger. In the absence of microbial stimulation, DCs and Ms constitutively expressed approximately 4000 genes, 96% of which were shared between the 2 cell types. In contrast, the genes altered transcriptionally in DCs and Ms following pathogen exposure were largely cell specific. Profiling of the gene expression data led to the identification of sets of tightly coregulated genes across all experimental conditions tested. A newly devised literature-based clustering algorithm enabled the identification of functionally and transcriptionally homogenous groups of genes. A comparison of the responses induced by the individual pathogens by means of this strategy revealed major differences in the functionally related gene profiles associated with each infectious agent. Although the intracellular pathogens induced responses clearly distinct from the extracellular B malayi, they each displayed a unique pattern of gene expression that would not necessarily be predicted on the basis of their phylogenetic relationship. The association of characteristic functional clusters with each infectious agent is consistent with the concept that antigen-presenting cells have prewired signaling patterns for use in the response to different pathogens.
authors.affiliation: Laboratory of Parasitic Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892, USA.
authors.forename: Damien
authors.initials: D
authors.lastname: Chaussabel
authors.forename: Roshanak Tolouei
authors.initials: RT
authors.lastname: Semnani
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: McDowell
authors.forename: David
authors.initials: D
authors.lastname: Sacks
authors.forename: Alan
authors.initials: A
authors.lastname: Sher
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Nutman
mesh_terms: D000818:Animals; D017951:Antigen Presentation / Q000235:genetics; D017178:Brugia malayi; D003199:Computer Systems; D003713:Dendritic Cells / Q000378:metabolism* / Q000382:microbiology / Q000469:parasitology; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D006801:Humans; D007893:Leishmania donovani; D008264:Macrophages / Q000378:metabolism* / Q000382:microbiology / Q000469:parasitology; D009000:Monocytes / Q000166:cytology; D009169:Mycobacterium tuberculosis; D020411:Oligonucleotide Array Sequence Analysis; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D014122:Toxoplasma; D014158:Transcription, Genetic
chemical_list: D012333:RNA, Messenger