Dengue virus specific T cells are involved in the pathogenesis of dengue virus infection / 第三军医大学学报

ABSTRACT

Objective To study the roles of dengue (DEN) virus specific T cells in the pathogenesis of DEN virus infection. Methods 2D42 cells, DEN virus specific CD8 + cell clones, were employed to investigate their in vivo function in DEN virus infection using an animal model. HepG2 was implanted into mice with severe combined immunodeficiency disease (HepG2-SCID) for the establishment of HepG2-SCID model. The animals were divided into 3 groups Group A HepG2-SCID mice were inoculated with 2D42 cells and then infected with DEN virus type 2 (DEN2) intraperitoneally; Group B HepG2-SCID mice were inoculated with normal mouse thymuscytes (NMT) and then intraperitoneally infected with DEN2; Group C HepG2-SCID mice were intraperitoneally infected with DEN2 alone. The mortality, viremia, and frequency of histopathological changes in the major organs of mice in the three groups were observed after infection. Results After inoculation of 2D42 cells, 80% infected mice showed severe clinical signs and died at the average 12.8 d after infection. The others only had transient manifestations, and then recovered from the disease and survived for more than 3 months. In contrast, after inoculation of NMT and /or DEN2 alone, 100% mortality rate was noted in these two groups. High viremia and frequency of histopathological changes in the major organs were observed in the mice in groups A and B. Conclusion Our data support both protective and pathogenic roles for DEN-specific CD8 + T cells in DEN virus infection.