title: TLR3- and MyD88-dependent signaling differentially influences the development of West Nile virus-specific B cell responses in mice following immunization with RepliVAX WN, a single-cycle flavivirus vaccine candidate.
abstract: Recognition of conserved pathogen-associated molecular patterns (PAMPs) by host pattern recognition receptors (PRRs) results in the activation of innate signaling pathways that drive the innate immune response and ultimately shape the adaptive immune response. RepliVAX WN, a single-cycle flavivirus (SCFV) vaccine candidate derived from West Nile virus (WNV), is intrinsically adjuvanted with multiple PAMPs and induces a vigorous anti-WNV humoral response. However, the innate mechanisms that link pattern recognition and development of vigorous antigen-specific B cell responses are not completely understood. Moreover, the roles of individual PRR signaling pathways in shaping the B cell response to this live attenuated SCFV vaccine have not been established. We examined and compared the role of TLR3- and MyD88-dependent signaling in the development of anti-WNV-specific antibody-secreting cell responses and memory B cell responses induced by RepliVAX WN. We found that MyD88 deficiency significantly diminished B cell responses by impairing B cell activation, development of germinal centers (GC), and the generation of long-lived plasma cells (LLPCs) and memory B cells (MBCs). In contrast, TLR3 deficiency had more effect on maintenance of GCs and development of LLPCs, whereas differentiation of MBCs was unaffected. Our data suggest that both TLR3- and MyD88-dependent signaling are involved in the intrinsic adjuvanting of RepliVAX WN and differentially contribute to the development of vigorous WNV-specific antibody and B cell memory responses following immunization with this novel SCFV vaccine.
authors.affiliation: Department of Microbiology and Immunology, University of Texas Medical Branch (UTMB), Galveston, Texas, USA.
authors.forename: Jingya
authors.initials: J
authors.lastname: Xia
authors.forename: Evandro R
authors.initials: ER
authors.lastname: Winkelmann
authors.forename: Summer R
authors.initials: SR
authors.lastname: Gorder
authors.forename: Peter W
authors.initials: PW
authors.lastname: Mason
authors.forename: Gregg N
authors.initials: GN
authors.lastname: Milligan
mesh_terms: D056704:Adaptive Immunity / Q000276:immunology*; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood; D000921:Antibody-Producing Cells / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology*; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D005260:Female; D005434:Flow Cytometry; D007114:Immunization; D008213:Lymphocyte Activation / Q000276:immunology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D053594:Myeloid Differentiation Factor 88 / Q000502:physiology*; D015398:Signal Transduction; D051196:Toll-Like Receptor 3 / Q000502:physiology*; D014901:West Nile Fever / Q000276:immunology* / Q000517:prevention & control; D053060:West Nile Virus Vaccines / Q000276:immunology* / Q000627:therapeutic use; D014902:West Nile virus / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; C507780:Myd88 protein, mouse; D053594:Myeloid Differentiation Factor 88; C519703:TLR3 protein, mouse; D051196:Toll-Like Receptor 3; D053060:West Nile Virus Vaccines