Association between immune cell subtypes and membranous nephropathy: A bidirectional Mendelian randomization study

Area of Science:

• Immunology
• Nephrology
• Genetics

Background:

• Membranous nephropathy (MN) is a kidney disease with complex etiology.
• The role of immune cells in MN pathogenesis is increasingly recognized.
• Understanding causal relationships between specific immune cell subtypes and MN is crucial for targeted therapies.

Purpose of the Study:

• To investigate the causal relationships between 731 immune cell subtypes and membranous nephropathy (MN) using a bidirectional two-sample Mendelian randomization (MR) approach.
• To identify specific immune cell subtypes that causally influence the risk or progression of MN.
• To provide robust genetic evidence for immune cell contributions to MN.

Main Methods:

• Utilized genome-wide association study (GWAS) data for 731 immune cell subtypes and MN.
• Employed inverse variance weighting (IVW) as the primary MR analysis method.
• Conducted sensitivity analyses using MR-Egger, weighted median, weighted mode, and heterogeneity tests to ensure robustness and rule out horizontal pleiotropy.

Main Results:

• Forward MR analysis revealed significant causal associations for 17 immune cell subtypes positively correlated with MN and 29 subtypes negatively correlated with MN (P < .05).
• Reverse MR analysis indicated significant associations between MN and 2 positively correlated immune cell subtypes and 4 negatively correlated subtypes (P < .05).
• No significant horizontal pleiotropy was detected, supporting the validity of the identified causal links.

Conclusions:

• This comprehensive bidirectional MR study establishes robust causal links between specific immune cell subtypes and membranous nephropathy.
• Findings underscore the intricate interplay between distinct immune cell populations and MN pathogenesis.
• Identified causal immune subtypes may represent novel therapeutic targets for managing MN.