The role of immune cell signatures in the pathogenesis of ovarian-related diseases: a causal inference based on mendelian randomization

Background: Immune cells play a pivotal role in maintaining ovarian function. However, the specific contributions of different immune cell phenotypes to the pathogenesis of specific ovarian-related diseases remain poorly understood. We aim to investigate the correlation between 731 immunophenotypes and ovarian-related diseases. Materials and Methods: Utilizing publicly available genetic data, we undertook a series of quality control measures to identify instrumental variables (IVs) associated with exposure. Subsequently, we conducted two-sample Mendelian randomization (MR) using inverse variance weighting to explore the causal relationships between 731 immune cell features and six ovarian-related diseases: ovarian cysts, ovarian dysfunction, premature ovarian failure (POF), polycystic ovary syndrome (PCOS), benign neoplasm of ovary, and malignant neoplasm of ovary at the genetic level. Sensitivity analyses, including leave-one-out and other MR analysis models, were performed. Finally, Bayesian colocalization (COLOC) analysis was employed to identify specific co-localized genes, thereby validating the MR results. Results: At the significance level corrected by Bonferroni, four immune phenotypes, including CD25 on IgD- CD38- B cells, were associated with ovarian cysts; four immune phenotypes, including CD39+ CD4+ T cell Absolute Count, were associated with ovarian dysfunction; eight immune phenotypes, including SSC-A on HLA DR+ CD8+ T cells, were associated with POF; five immune phenotypes, including CD20- CD38- B cell Absolute Count, were associated with PCOS; five immune phenotypes, including CD4+ CD8dim T cell Absolute Count, were associated with benign ovarian tumors; and three immune phenotypes, including BAFF-R on IgD- CD38+ B cells, were associated with malignant ovarian tumors. Sensitivity analysis indicated robust results. COLOC analysis identified four immune cell co-localized variants (rs150386792, rs117936291, rs75926368, rs575687159) with ovarian diseases. Conclusion: Our study elucidates the close genetic associations between immune cells and six ovarian-related diseases, thereby providing valuable insights for future research endeavors and clinical applications.