The effects of Treponema pallidum on human dendritic cells.
Cell mediated immune responses play a prominent role in syphilis, which is caused by Treponema pallidum. The role of dendritic cells (DC) in the syphilitic infection is not well understood in human. In the present study, we studied interaction of T. pallidum with DC, generated from human peripheral blood mononuclear cells with GM-CSF and IL-4. After adding T. pallidum for 16 hours to immature DC at culture day 7, the change of surface antigens on DC was monitored by flow cytometry, the amount of IL-12 in culture supernatant of DC was measured by ELISA and T cell stimulatory capacity of DC was checked in mixed lymphocyte reaction (MLR). We have observed an efficient phagocytosis of T. pallidum by electron microscopy as early as 2 hours after addition of T. pallidum to DC. Interaction of DC with T. pallidum resulted in increased surface expression of CD83 which was proportionally increased according to the number of T. pallidum. Expressions of CD80, CD86 and HLA-DR on DC were slightly increased. The amount of IL-12 in the culture supernatant of DC was increased (1,099 pg/ml) after the addition of T. pallidum. T. pallidum-infected DC also displayed enhanced T cell stimulatory capacity in MLR. As seen from the above, we observed phagocytosis of T. pallidum by DC as early as 2 hours after addition of T. pallidum to DC and found that T. pallidum can stimulate DC maturation which mean that DC modulate an protective immune response during T. pallidum infection.
Shin
Jong Lan
JL
Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, BK21 Project for Medical Science, Yonsei University, 134 Shinchon-dong, Seodaemun-gu, Seoul 120-752, Korea.
Chung
Kee Yang
KY
Kang
Jin Moon
JM
Lee
Tae Hyung
TH
Lee
Min Geol
MG
D002478:Cells, Cultured; D003713:Dendritic Cells / Q000166:cytology / Q000276:immunology* / Q000382:microbiology*; D006801:Humans; D018664:Interleukin-12 / Q000378:metabolism; D007959:Lymphocyte Culture Test, Mixed; D008854:Microscopy, Electron; D010587:Phagocytosis / Q000276:immunology; D011956:Receptors, Cell Surface / Q000276:immunology / Q000378:metabolism; D013587:Syphilis / Q000276:immunology*; D013601:T-Lymphocytes / Q000276:immunology; D014210:Treponema pallidum / Q000276:immunology* / Q000648:ultrastructure
D011956:Receptors, Cell Surface; D018664:Interleukin-12