title: A sensitive high-throughput assay for evaluating host-pathogen interactions in Cryptococcus neoformans infection.
abstract: BACKGROUND
  Cryptococcus neoformans causes serious disease in immunocompromised individuals, leading to over 600,000 deaths per year worldwide. Part of this impact is due to the organism's ability to thwart what should be the mammalian hosts' first line of defense against cryptococcal infection: internalization by macrophages. Even when C. neoformans is engulfed by host phagocytes, it can survive and replicate within them rather than being destroyed; this ability is central in cryptococcal virulence. It is therefore critical to elucidate the interactions of this facultative intracellular pathogen with phagocytic cells of its mammalian host.
  
  
  RESULTS
  To accurately assess initial interactions between human phagocytic cells and fungi, we have developed a method using high-throughput microscopy to efficiently distinguish adherent and engulfed cryptococci and quantitate each population. This method offers significant advantages over currently available means of assaying host-fungal cell interactions, and remains statistically robust when implemented in an automated fashion appropriate for screening. It was used to demonstrate the sensitivity of human phagocytes to subtle changes in the cryptococcal capsule, a major virulence factor of this pathogen.
  
  
  CONCLUSIONS
  Our high-throughput method for characterizing interactions between C. neoformans and mammalian phagocytic cells offers a powerful tool for elucidating the relationship between these cell types during pathogenesis. This approach will be useful for screens of this organism and has potentially broad applications for investigating host-pathogen interactions.
authors.affiliation: Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America.
authors.forename: Deepa
authors.initials: D
authors.lastname: Srikanta
authors.forename: Meng
authors.initials: M
authors.lastname: Yang
authors.forename: Matthew
authors.initials: M
authors.lastname: Williams
authors.forename: Tamara L
authors.initials: TL
authors.lastname: Doering
mesh_terms: D000818:Animals; D001331:Automation; D002448:Cell Adhesion; D002478:Cells, Cultured; D003453:Cryptococcosis / Q000276:immunology / Q000382:microbiology*; D003455:Cryptococcus neoformans / Q000472:pathogenicity* / Q000502:physiology; D005260:Female; D057166:High-Throughput Screening Assays; D054884:Host-Pathogen Interactions; D006801:Humans; D007546:Isoquinolines; D008264:Macrophages / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D009000:Monocytes / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D010586:Phagocytes / Q000276:immunology / Q000382:microbiology*; D010587:Phagocytosis; D014774:Virulence
chemical_list: D007546:Isoquinolines; C017475:lucifer yellow