The role of plasmacytoid dendritic cells as a new immune cells in the pathogenesis of chronic hepatitis C, chronic hepatitis B and HIV

The objective. To establish the nature and degree of participation of plasmacytoid dendritic cells (pDCs) in the immunogenesis of chronic hepatitis C, hepatitis b and HIV infection, by comparative determination of the number and functional activity of pDCs in these infections. Patients and methods. We examined 123 persons. 62 patients of them with chronic hepatitis C, 21 with chronic hepatitis B, 28 HIV patients and 12 healthy individuals. The pDC number was enumerated by flow cytometry. In vitro IFN production in the whole blood in response to pDC-specific stimulus unmethylated CpG oligonucleotides was determined by ELISA. Results. It was found that the percentage and absolute number of pDCs of all patients was below the same indicators of healthy individuals (p < 0.05). In the CHC patients as an absolute (8.3 ± 0.7) and relative (0.2 ± 0.015) pDCs content was significantly higher than in hepatitis B (4,3 ± 0.7 and 0.11 ± 0.02) (p < 0.0001 and p = 0.002 respectively) and HIV patients (5.25 ± 0.7 and 0.13 ± 0.015); (p = 0.003 and p = 0.003). Production of IFN pDCs was higher in HCV and chronic hepatitis B patients against the indicators of healthy individuals. However, we have not established reliable differences between the quantitative content of pDCs in patients with hepatitis B and HIV-infected patients (p = 0.35 and p = 0.5 respectively), which may play a crucial role in the escape mechanisms of these infections from the action of the immune system. A particularly important role in the pathogenesis of these infections plays the functional state of pDCs. Shown stimulation of IFN production of pDCs in response to viral infection in patients with CHC and CHB vs index in healthy individuals. While patients with CHC production of IFN is significantly higher (203.7 ± 54.4) than in chronic hepatitis B (7.9 ± 1.9; p = 0.007), whereas in patients with HIV infection it is not detected and does not differ from that in healthy individuals. Conclusion. It is shown that the characteristics of the state of pDCs with infectious diseases of various etiologies have significant differences. The reduction of the content of pDCs compared with healthy individuals noted in chronic infections, however, the level of decrease depends on the etiology of the pathogen and stage of the disease. In such infectious diseases as viral hepatitis B and HIV infection there quantitative defect was marked in this cell population. Functional activity (interferonogenesis) in pDCs is maximally expressed when HCV is less significant with CHB, whereas in HIV-infected patients in General, paralyzed and does not differ from that of healthy people. These data demonstrate the close relationship activities of plasmacytoid dendritic cells with the pathogenesis and course of the studied infections, it is important to find new approaches to their treatment.