Characteristics of peripheral blood lymphocyte subsets in patients with neuromyelitis optica

Background: Neuromyelitis spectrum disorder (NMOSD) is inflammatory disease of the central nervous system (CNS), mainly affecting the optic nerve and/or spinal cord, and characterized by the presence of aquaporin-4 immunoglobulin G antibody (AQP4-IgG) in the serum. The role and activity of different lymphocyte subsets are crucial for understanding the immune mechanisms and pathogenesis of NMOSD. This study aimed to analyze the levels of lymphocyte subsets in NMOSD patients.Methods: 22 NMOSD patients and 22 individuals without autoimmune diseases were enrolled. Lymphocyte subsets were measured in both groups, including CD3 + cells, CD3 + CD4 + T cells, CD3 + CD8 + T cells, CD19 + B cells, CD3- CD(16/56) + natural killer cells (NK cells), and CD4+/CD8 + ratio, along with the routine peripheral blood lymphocyte percentage. The data were analyzed using SPSS 22.0.Results: The total lymphocyte percentage in routine peripheral blood tests were significantly lower in the NMOSD group compared to controls (p < 0.05). Lymphocyte subset analysis revealed the NMOSD group had a significantly higher proportion of CD3 + CD8 + T cells compared to controls. Additionally, the CD4+/CD8 + T cell ratio was significantly lower in the NMOSD group. No significant differences were observed in the proportions of CD3 + cells, CD3 + CD4 + T cells, CD19 + B cells, or CD3-CD56/16 + NK cells between groups. The total lymphocyte percentage showed a positively correlated with the disease duration(r² = 0.2529, P = 0.017).Conclusion: This study suggests that T cell levels, and CD4/CD8 ratio are connected with the occurrence and development of NMOSD. We observed a reduced total lymphocyte percentage in routine blood tests, an elevated proportion of CD3 + CD8 + T cells and a decreased CD4+/CD8 + T cell ratio compared to controls. These immunological changes show associations with NMOSD status, with the total lymphocyte percentage positively correlating with disease duration. Further investigation of these immune parameters may offer potential avenues for monitoring disease progression and developing adjunctive therapeutic strategies for NMOSD.