title: Tick saliva regulates migration, phagocytosis, and gene expression in the macrophage-like cell line, IC-21.
abstract: We studied the effects of tick saliva on cell migration, cell signaling, phagocytosis, and gene expression in the murine macrophage cell line, IC-21. Saliva increased both basal- and platelet-derived growth factor (PDGF)-stimulated migration in IC-21 cells. However, saliva did not affect PDGF-stimulated extracellular signal-regulated kinase (ERK) activity. Zymosan-mediated interleukin-1 receptor associated kinase (IRAK) activity increased when cells were pretreated with saliva. Saliva suppressed phagocytosis of zymosan particles by IC-21 cells. An RT(2) Profiler™ PCR Array revealed that saliva regulates gene expression in a manner consistent with an immune response skewed toward a Th2 reaction, which is characterized by production of anti-inflammatory cytokines IL-4 and IL-10. Our results using IC-21 cells suggest that Dermacentor variabilis has evolved a mechanism for regulating macrophage function, which may contribute to the tick's ability to modulate immune function.
authors.affiliation: Department of Biological Sciences, The University of Memphis, Memphis, TN 38152, United States. cdkramer@memphis.edu
authors.forename: Carolyn D
authors.initials: CD
authors.lastname: Kramer
authors.forename: Nina M
authors.initials: NM
authors.lastname: Poole
authors.forename: Lewis B
authors.initials: LB
authors.lastname: Coons
authors.forename: Judith A
authors.initials: JA
authors.lastname: Cole
mesh_terms: D000818:Animals; D001096:Arachnid Vectors / Q000502:physiology*; D002460:Cell Line; D002465:Cell Movement; D002634:Chemotaxis, Leukocyte; D003870:Dermacentor / Q000502:physiology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D048049:Extracellular Signal-Regulated MAP Kinases / Q000502:physiology; D005260:Female; D015870:Gene Expression; D008264:Macrophages / Q000276:immunology / Q000502:physiology*; D008297:Male; D051379:Mice; D010587:Phagocytosis; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology; D016133:Polymerase Chain Reaction; D011817:Rabbits; D012463:Saliva / Q000502:physiology; D013047:Specific Pathogen-Free Organisms
chemical_list: D010982:Platelet-Derived Growth Factor; D048049:Extracellular Signal-Regulated MAP Kinases