ABSTRACT
Objective To explore the expression level and clinical significance of multifunctional CD8 T cells in patients with tuberculosis (TB). Methods The expression levels of MTB antigen specific and non-specific multifunctional CD8 T cells among peripheral blood mononuclear cells (PBMCs) and pleural fluid mononuclear cells (PFMCs) in TB patients, latent tuberculosis infection patients (LTBI) and healthy controls (HC) were measured by flow cytometry. Results The expression level of multifunctional CD8 T cells (IL-2+IFN-γ+TNF-α+CD8 T cells) among PBMCs stimulated by non-specific MTB antigen in TB patients was (5.72 ± 4.32)%, which was significantly lower than those in HC and LTBI [(22.3 ± 15.7)%, q=7.455, P<0.001;(14.2 ± 7.72)%, q=3.110, P<0.05]. Under the stimulation by specific MTB antigen, the expression level of multifunctional CD8 T cells among PBMCs in TB patients was (0.33 ± 0.83)%, which was significantly higher than those in HC and LTBI [(0.017 ± 0.03)%, q=3.97, P<0.05;(0.019 ± 0.035)%, q=3.39, P<0.05]. In patients with tuberculous pleurisy, the expression level of multifunctional CD8 T cells among PFMCs was (0.623 ± 1.033)%, which was significantly higher than that among PBMCs [(0.034 ± 0.066)%, P<0.001]. The expression level of multifunctional CD8 T cells in TB patients was negatively correlated with HRCT score (r=-0.265 8, P=0.015 8). Conclusion The expression level of multifunctional CD8 T cells was contributed to discriminate TB patients from latent tuberculosis infection patients , and was closely related to the degree of damage in lung.