Dengue virus inoculation to human skin explants: an effective approach to assess in situ the early infection and the effects on cutaneous dendritic cells.
Although dengue virus (DV) enters through skin while mosquitoes feed, early contacts remain unexplored regarding the cutaneous viral fate and in situ immune responses. We addressed this by exposing healthy, non-cadaveric, freshly obtained human skin explants to a human DV2 isolate. We demonstrated negative-strand DV-RNA and non-structural protein-1, both suggestive of viral replication in skin. Although control, mock-infected and DV-infected explants showed less (MHC-CII(+)/CD1a(+)/Langerin+) Langerhans cells, deranged morphology and decreased frequency were more apparent in DV-infected explants. Whereas DV+ cells were infrequent in epidermis and completely absent in dermis, some areas of basal epidermis were clearly DV+, presumably keratinocytes, cells where TUNEL positivity revealed apoptosis. Unlike fresh, control and mock-infected skin, DV-infected explants expressed CD80 and CD83, indicative of dendritic cell (DC) activation and maturation, respectively. However, sequential sections indicated that these cells were not DV+, suggesting that activated/mature DCs capable of priming T cells, probably, were not infected. Alternatively, the occasionally infected epidermal DC might not have reached maturation. Interestingly, skin DV infection apparently uncouples the DC activation/maturation process from another crucial DC function, the subsequent migration into dermis. This was suggested, because upon cutaneous DV infection, the few emerging CD83+ (mature) DCs remained within the outer epidermis, while no dermal CD83+ DCs were observed. These paradoxical effects might represent unknown DV subversion strategies. This approach is relatively easy, quick (results in 48 h), economical for developing countries where dengue is re-emerging and advantageous to evaluate in situ viral biology, immunity and immunopathology and potential antiviral strategies.
Limon-Flores
Alberto Yairh
AY
Department of Experimental Pathology, Center for Advanced Research, CINVESTAV-IPN, Mexico City, Mexico. leflores@cinvestav.mx
Perez-Tapia
Mayra
M
Estrada-Garcia
Iris
I
Vaughan
Gilberto
G
Escobar-Gutierrez
Alejandro
A
Calderon-Amador
Juana
J
Herrera-Rodriguez
Sara Elisa
SE
Brizuela-Garcia
Adriana
A
Heras-Chavarria
Monica
M
Flores-Langarica
Adriana
A
Cedillo-Barron
Leticia
L
Flores-Romo
Leopoldo
L
D017209:Apoptosis; D003713:Dendritic Cells / Q000276:immunology* / Q000821:virology; D003715:Dengue / Q000276:immunology*; D003716:Dengue Virus / Q000472:pathogenicity*; D004817:Epidermis / Q000276:immunology* / Q000473:pathology / Q000821:virology; D005260:Female; D006801:Humans; D017403:In Situ Hybridization; D012367:RNA, Viral / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D046509:Tissue Culture Techniques; D014611:Vaccination / Q000379:methods; D017361:Viral Nonstructural Proteins / Q000032:analysis; D014773:Virology / Q000379:methods; D014779:Virus Replication
C079340:NS1 protein, Dengue virus type 2; D012367:RNA, Viral; D017361:Viral Nonstructural Proteins