More than 40%of HIV infections occur via female reproductive tract(FRT)through heterosexual transmission.Epithelial cells that line the female genital mucosa are the first line of defense against HIV-1 and other sexua...More than 40%of HIV infections occur via female reproductive tract(FRT)through heterosexual transmission.Epithelial cells that line the female genital mucosa are the first line of defense against HIV-1 and other sexually transmitted pathogens.These sentient cells recognize and respond to external stimuli by induction of a range of carefully balanced innate immune responses.Previously,we have shown that in response to HIV-1 gp120,the genital epithelial cells(GECs)from upper reproductive tract induce an inflammatory response that may facilitate HIV-1 translocation and infection.In this study,we report that the endometrial and endocervical GECs simultaneously induce biologically active interferon-β(IFNβ)antiviral responses following exposure to HIV-1 that act to protect the epithelial tight junction barrier.The innate antiviral response was directly induced by HIV-1 envelope glycoprotein gp120 and addition of gp120 neutralizing antibody inhibited IFNβproduction.Interferon-βwas induced by gp120 in upper GECs through Toll-like receptor 2 signaling and required presence of heparan sulfate on epithelial cell surface.The induction of IFNβwas dependent upon activation of transcription factor IRF3(interferon regulatory factor 3).The IFNβwas biologically active,had a protective effect on epithelial tight junction barrier and was able to inhibit HIV-1 infection in TZM-bl indicator cells and HIV-1 replication in T cells.This is the first report that recognition of HIV-1 by upper GECs leads to induction of innate antiviral pathways.This could explain the overall low infectivity of HIV-1 in the FRT and could be exploited for HIV-1 prophylaxis.展开更多
Salmonella enterica serovar Typhi is a pathogen that only infects humans.Currently,there is no animal model for studying this pathogen.Recently,alymphoid RAG2^(-/-)/γc^(-/-) mice engrafted with human leukocytes,known...Salmonella enterica serovar Typhi is a pathogen that only infects humans.Currently,there is no animal model for studying this pathogen.Recently,alymphoid RAG2^(-/-)/γc^(-/-) mice engrafted with human leukocytes,known as humanized mice,have been successfully utilized to develop experimental models for several human-specific viral infections,including HIV,human-like dengue fever and hepatitis C virus.Little is known about the usefulness and feasibility of the humanized mouse model for the study of human-specific bacterial pathogens,such as S.typhi.The aim of this study was to determine if Salmonella enterica serovar Typhi could establish productive infection in humanized mice.Here we report that intravenous inoculation of S.typhi into humanized mice,but not controls,established S.typhi infections.High bacterial loads were found in the liver,spleen,blood and bone marrow of mice reconstituted with human leukocytes,but not in the unreconstituted control mice.Importantly,S.typhi-infected humanized mice lost significant body weight,and some of the infected mice displayed neurological symptoms.Our data suggest,for the first time,that humanized mice are susceptible to S.typhi challenge and that this model can be utilized to study the pathogenesis of S.typhito develop novel therapeutic strategies.展开更多
基金by grants from the Canadian Institutes of Health Research(CIHR)Operating Grant FRN 126019(to CK)CIHR Team Grant on Mucosal Immunology of HIV Vaccine Development FRN 138657(to CK)+1 种基金the Ontario HIV Treatment Network(OHTN)Applied HIV Research Chair AHRC 779(to CK)VHF was supported by CIHR Banting Scholarship.
文摘More than 40%of HIV infections occur via female reproductive tract(FRT)through heterosexual transmission.Epithelial cells that line the female genital mucosa are the first line of defense against HIV-1 and other sexually transmitted pathogens.These sentient cells recognize and respond to external stimuli by induction of a range of carefully balanced innate immune responses.Previously,we have shown that in response to HIV-1 gp120,the genital epithelial cells(GECs)from upper reproductive tract induce an inflammatory response that may facilitate HIV-1 translocation and infection.In this study,we report that the endometrial and endocervical GECs simultaneously induce biologically active interferon-β(IFNβ)antiviral responses following exposure to HIV-1 that act to protect the epithelial tight junction barrier.The innate antiviral response was directly induced by HIV-1 envelope glycoprotein gp120 and addition of gp120 neutralizing antibody inhibited IFNβproduction.Interferon-βwas induced by gp120 in upper GECs through Toll-like receptor 2 signaling and required presence of heparan sulfate on epithelial cell surface.The induction of IFNβwas dependent upon activation of transcription factor IRF3(interferon regulatory factor 3).The IFNβwas biologically active,had a protective effect on epithelial tight junction barrier and was able to inhibit HIV-1 infection in TZM-bl indicator cells and HIV-1 replication in T cells.This is the first report that recognition of HIV-1 by upper GECs leads to induction of innate antiviral pathways.This could explain the overall low infectivity of HIV-1 in the FRT and could be exploited for HIV-1 prophylaxis.
基金This study was supported by a grant from CIHR to Ali A Ashkar.AAA is a recipient of a Career Award in Health Sciences from Rx&D/CIHR.
文摘Salmonella enterica serovar Typhi is a pathogen that only infects humans.Currently,there is no animal model for studying this pathogen.Recently,alymphoid RAG2^(-/-)/γc^(-/-) mice engrafted with human leukocytes,known as humanized mice,have been successfully utilized to develop experimental models for several human-specific viral infections,including HIV,human-like dengue fever and hepatitis C virus.Little is known about the usefulness and feasibility of the humanized mouse model for the study of human-specific bacterial pathogens,such as S.typhi.The aim of this study was to determine if Salmonella enterica serovar Typhi could establish productive infection in humanized mice.Here we report that intravenous inoculation of S.typhi into humanized mice,but not controls,established S.typhi infections.High bacterial loads were found in the liver,spleen,blood and bone marrow of mice reconstituted with human leukocytes,but not in the unreconstituted control mice.Importantly,S.typhi-infected humanized mice lost significant body weight,and some of the infected mice displayed neurological symptoms.Our data suggest,for the first time,that humanized mice are susceptible to S.typhi challenge and that this model can be utilized to study the pathogenesis of S.typhito develop novel therapeutic strategies.