Dengue virus serotype-2 impairs proliferation of healthy donors' T lymphocytes.
OBJECTIVE
T lymphocytes are not infected by dengue virus (DENV), nevertheless it is possible that exposure to DENV may affect their function. T lymphocytes from DENV-infected individuals are impaired in their proliferative capacity, although this effect has been attributed to altered function of antigen-presenting cells rather than to an intrinsic defect on T lymphocytes. Here we analyzed whether T lymphocytes from healthy donors became impaired in their proliferative capacity following in vitro exposure to DENV serotype-2 (DENV-2), as well as the possible mechanisms for this.


METHODS
Isolated CD4+ and CD8+ T lymphocytes from healthy donors were in vitro exposed to DENV-2, before polyclonal activation, cell proliferation, IL-2 synthesis. IL-2Rα expression, nuclear translocation of NF-AT and NF-κB, and intracellular calcium flux were assessed.


RESULTS
In vitro exposure of both CD4+ and CD8+ T lymphocytes from healthy donors to DENV-2 impairs cell proliferation, IL-2 synthesis, and IL-2Rα (CD25) cell membrane expression. Signalling wise, exposure to DENV-2 impairs the nuclear translocation of NF-AT, downstream of intracellular calcium mobilization, as well as that of NF-κB.


CONCLUSIONS
In the course of a dengue infection, direct exposure of T lymphocytes to DENV could affect cell-mediated immune responses.
Departamento de Inmunología, Escuela Nacional de Ciencias Biológicas, Instituto Politécnico Nacional, México D.F., México.
C J
CJ
Fuentes-Miranda
F J
FJ
Sánchez-García
A R
AR
Coker
O
O
Rojas-Espinosa
R
R
Salinas-Tobón
M M B
MM
Moreno-Altamirano
D049109:Cell Proliferation; D002478:Cells, Cultured; D003716:Dengue Virus / Q000276:immunology*; D054884:Host-Pathogen Interactions; D006801:Humans; D057131:Immune Evasion; D007376:Interleukin-2 / Q000378:metabolism; D016328:NF-kappa B / Q000378:metabolism; D050778:NFATC Transcription Factors / Q000378:metabolism; D015375:Receptors, Interleukin-2 / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000276:immunology* / Q000821:virology*
D007376:Interleukin-2; D016328:NF-kappa B; D050778:NFATC Transcription Factors; D015375:Receptors, Interleukin-2