Expression of Progranulin and its related mechanism with exosomes from peripheral blood mononuclear cells CD4 + T cells in patients with thyroid-associated ophthalmopathy

Background: The expression of serum progranulin (PGRN) and the related immunological mechanisms of peripheral blood mononuclear cells (PBMCs) CD4 + T cells exosomes in thyroid-associated ophthalmopathy (TAO) are currently hot topics of research. Material and Method: A total of 27 patients with active TAO and 59 healthy individuals were included in the study for comparison. PBMCs were isolated from the patients' blood, and naïve CD4+ T cells were purified using human naïve CD4 microbeads. One co-culture group was not supplemented with PGRN, serving as the PGRN-untreated group (AG), while another group was supplemented with extracted PGRN, serving as the PGRN-treated group (BG). CD4+ T cells derived from the blood of healthy individuals were used as the control group (CG). Result: The serum PGRN concentration in TAO patients was visibly higher as against the CG; The contents of interleukin (IL-10), IL-4, and IL-17 in BG were visibly lower as against AG; The protein and mRNA expression of cytokines in BG were visibly lower as against AG; The proliferation level of CD4 + T cells was visibly lower, and the apoptosis level was visibly higher in BG as against AG (P < 0.05). Conclusion: PGRN may be implicated in the pathogenesis of TAO. It could modulate the immune response by reducing cytokine release in CD4+ T cell-derived exosomes, inhibiting the proliferation of CD4+ T cells, and promoting their apoptosis.