The role of endocervical immunity in HPV persistence

Objective: We aimed to evaluate systemic inflammatory markers, peripheral blood and endocervical cytobrush derived immune cells with flow cytometry in Human papillomavirus (HPV) persistent and nonpersistent patient populations. Method: Premenopausal 19 patients with HPV persistence and 22 patients with HPV clearance who applied to Akdeniz University Faculty of Medicine, obstetrics and gynecology outpatient clinic were included in the study. Peripheral venous blood and endocervical cytobrush samples taken simultaneously from these patients were subjected to immunophenotyping analysis with multicolor flow cytometry , and lymphocyte percentages and phenotypes were compared. Systemic inflammation markers were also analyzed from peripheral venous blood. Results: Peripheral venous blood absolute lymphocyte count was found to be lower in the HPV persistence group than in the clearance group (1.9 vs 2.5 x103 / µl, p.004). Neutrophil/lymphocyte ratio (NLR) was higher in the persistence group than in the clearance group. (2.4 vs1.6, p.024). The percentage of CD3+CD8+ T lymphocytes was found to be lower in the persistence group than in the clearance group (24.5 vs 35.8 %, p .014). The percentage of CD8+ cells in Gammadelta T lymphocyte (GDT) was found to be lower in the persistence group than in the clearance group ( 22.6 vs 32.2 %, p .021). The percentage of CD3-GDT was higher in the clearance group (3.4 vs 11.5 %, p .013). In the endocervical cytobrush analysis, total CD3+T lymphocyte, CD3+CD8+ T lymphocyte, CD8+GDT, CD4-CD8- ratio in GDT, CD8+ ratio in GDT were lower in the persistence group. (52 vs 73.6 %, p.004), (9.8 vs 20.2 %, p .013), (7.2 vs 15.1 % , p .030), (51.1 vs 69.6%, p.041), (9 vs 15 %, p.048) respectively. The percentage of CD3+CD4+ T lymphocyte and CD4+GDT was found to be higher in the persistence group than in the clearance group. (37.6 vs 14.1 %, p.002), (38.6 vs 15.0 %, p .004) respectively. Conclusion: There are significant differences in systemic and local immunity in HPV persistence. This difference is clearly against CD8+ lymphocytes and in favor of CD4+ lymphocytes in endocervical mucosa. The difference in endocervical mucosa is mainly due to GDT cells.