Hairy cell (HC) transformation of human peripheral blood lymphocytes (PBL) by Coxiella burnetii was studied to clarify the significance of persistency of C. burnetii in a hairy cell line (designated "TOL"). TOL cells which exhibited HC characteristics in hairy cell leukemia (HCL) were persistently infected with C. burnetii. Two strains of C. burnetii, our isolate from TOL cells and the original isolate in 1935, the Nine Mile strain from American Type Culture Collection (ATCC, U.S.A), were inoculated to PBL cultures. HC transformation not only by our isolates (87%) but also by Nine Mile strain (100%) was demonstrated in an average of 20 days. The original observation that Coxiella induced HC transformation in vitro was also confirmed in experiments with PBL exposed to C. burnetii in vivo. Spontaneous development of HC were observed in cultures of PBL only from coxiellemic cases (12/24) but not from C. burnetii negative cases (0/57). All HC cell lines (34) as determined by their morphology and cytochemical markers of HC in HCL remained infected with C. burnetii invariably.
Blood Cells/*microbiology/*ultrastructure ; Cell Line ; *Cell Transformation, Neoplastic ; Coxiella burnetii/isolation & purification/*physiology ; Human ; Leukemia, Hairy Cell/microbiology/*pathology ; Lymphocytes/*microbiology/*ultrastructure ; Microscopy, Electron, Scanning ; Support, Non-U.S. Gov't

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, 099pg/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.
Cells, Cultured ; Dendritic Cells/cytology/*immunology/*microbiology ; Human ; Interleukin-12/metabolism/secretion ; Lymphocyte Culture Test, Mixed ; Microscopy, Electron ; Phagocytosis/immunology ; Receptors, Cell Surface/immunology/metabolism ; Support, Non-U.S. Gov't ; Syphilis/*immunology ; T-Lymphocytes/immunology ; Treponema pallidum/*immunology/ultrastructure