title: Contribution of FcɛRI-associated vesicles to mast cell-macrophage communication following Francisella tularensis infection.
abstract: Understanding innate immune intercellular communication following microbial infection remains a key biological issue. Using live cell imaging, we demonstrate that mast cells actively extend cellular projections to sample the macrophage periphery during Francisella tularensis LVS infection. Mast cell MHCII(hi) expression was elevated from less than 1% to 13% during LVS infection. Direct contact during co-culture with macrophages further increased mast cell MHCII(hi) expression to approximately 87%. Confocal analyses of the cellular perimeter revealed mast cell caspase-1 was localized in close proximity with FcɛRI in uninfected mast cells, and repositioned to clustered regions upon LVS infection. Importantly, mast cell FcɛRI-encompassed vesicles are transferred to macrophages by trogocytosis, and macrophage caspase-1 expression is further up-regulated upon direct contact with mast cells. Our study reveals direct cellular interactions between innate cells that may impact the function of caspase-1, a known sensor of microbial danger and requirement for innate defense against many pathogenic microbes including F. tularensis.
authors.affiliation: RCMI, Biophotonics Core, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA.
authors.forename: Annette R
authors.initials: AR
authors.lastname: Rodriguez
authors.affiliation: South Texas Center for Emerging Infectious Diseases, Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA.
authors.forename: Jieh-Juen
authors.initials: JJ
authors.lastname: Yu
authors.affiliation: Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA.
authors.forename: Christopher
authors.initials: C
authors.lastname: Navara
authors.affiliation: South Texas Center for Emerging Infectious Diseases, Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA.
authors.forename: James P
authors.initials: JP
authors.lastname: Chambers
authors.affiliation: South Texas Center for Emerging Infectious Diseases, Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA.
authors.forename: M Neal
authors.initials: MN
authors.lastname: Guentzel
authors.affiliation: South Texas Center for Emerging Infectious Diseases, Department of Biology, University of Texas at San Antonio, One UTSA Circle, San Antonio, TX, USA bernard.arulanandam@utsa.edu.
authors.forename: Bernard P
authors.initials: BP
authors.lastname: Arulanandam
mesh_terms: D000818:Animals; D020170:Caspase 1 / Q000378:metabolism*; D002450:Cell Communication; D022081:Cell Surface Extensions / Q000378:metabolism / Q000473:pathology; D002478:Cells, Cultured; D018920:Coculture Techniques; D022162:Cytoplasmic Vesicles / Q000378:metabolism*; D005604:Francisella tularensis / Q000276:immunology*; D007113:Immunity, Innate; D008264:Macrophages / Q000276:immunology* / Q000382:microbiology; D008407:Mast Cells / Q000276:immunology* / Q000382:microbiology; D051379:Mice; D008810:Mice, Inbred C57BL; D018613:Microscopy, Confocal; D021381:Protein Transport; D017455:Receptors, IgE / Q000378:metabolism*; D014406:Tularemia / Q000276:immunology*
chemical_list: D017455:Receptors, IgE; D020170:Caspase 1
keywords: FcɛRI; Francisella; macrophages; mast cells; trogocytosis