Unconjugated
Chronic viral hepatitis C still remains the clinical challenge. Attempts of the immune system to cope with this infection are unsatisfactory. There is a conviction that the main site of interaction between virus (Hepatitis C virus, HCV) and immune system is in situ, i.e., in liver. Natural killer (NK) cells appeared relevant in the acute hepatitis. Less is known about the immune response in the chronic HCV infection. The aim of this study was to evaluate the prevalence of various cytotoxic cell subsets in chronic HCV+ liver tissue and to seek links between them and laboratory data of patients. Sections from paraffin blocks of liver biopsy tissues of HCV+ untreated patients were subjected to the reaction with antibodies vs. cytotoxic cell subsets and immunohistochemistry. Positive cells were searched in cellular infiltrates in portal areas and in liver parenchyma. They were classified on the “Yes” or “No” basis. Majority of liver biopsies exhibited cellular infiltrates in portal spaces and as single cells in liver parenchyma. Infiltrates consisted of CD8+ T cells, CD56+ NK ones, including CD158i+ and CD158b+. The latter were rarely seen. There were also granzyme B+ cells. The most abundant were NKG2D+ cells, much more common than NK CD56+ ones. It implied that NKG2D was also expressed on T cells. Prevalence of NKG2D+ cells correlated with high activity of liver enzymes such as alanine aminotransferase, aspartate aminotransferase and a greater histological severity of liver injury. NKG2D+ cells form the bulk of cells infiltrating HCV-infected human liver. Correlation of NKG2D+ cells with some laboratory parameters of patients suggests their role in hepatitis C pathogenesis.
BACKGROUND:
Periodontal disease is chronic inflammatory process that affects the attachment structures of the teeth and constitutes a significant cause of tooth loss in adults. Although different bacteria play an important role in the triggering of this condition, the progression and severity of the disease are strongly affected by the host immune response, which is under the control of different immune regulatory mechanisms, including T regulatory (Treg) cells. The aim of this study was to assess the frequency and function of CD69+ Treg lymphocytes in patients with chronic periodontal disease.
METHODS:
Peripheral blood samples (n = 33) and gingival tissue (n = 9) were obtained from patients with chronic periodontal disease. Blood samples from 25 healthy individuals were also studied. Levels of CD69+ Treg lymphocytes in peripheral blood and gingival tissue were determined by six-color multiparametric flow cytometry, immunofluorescence, and immunohistochemistry. The immune regulatory function of CD69+ Treg cells was tested by an in vitro assay of inhibition of lymphocyte activation.
RESULTS:
Percentages of CD69+ Treg cells were significantly higher in the peripheral blood from patients with active periodontal disease compared to healthy controls, and these percentages inversely correlated with the periodontal attachment loss. Increased numbers of these Treg cells were detected in the gingival tissue from active PD patients compared to their peripheral blood. However, the suppressive function of CD69+ Treg cells was significantly diminished in patients with periodontal disease compared to healthy controls.
CONCLUSIONS:
Our data suggest that CD69+ Treg cells seem to be another important piece in the complex immunopathogenesis of periodontal disease.
© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.