Identification of biomarkers associated with macrophage infiltration in non-obstructive azoospermia using single-cell...

Area of Science:

• Male reproductive health
• Infertility research
• Immunology of reproduction

Background:

• Non-obstructive azoospermia (NOA) is a frequent cause of male infertility.
• The role of macrophages in NOA pathogenesis is not well understood.
• Macrophages are implicated in testicular function, but their specific involvement in NOA requires investigation.

Purpose of the Study:

• To investigate the significance of macrophage infiltration in NOA.
• To identify macrophage-related biomarkers for NOA.
• To explore the functional roles of identified genes in NOA.

Main Methods:

• Utilized gene expression microarray (GSE45885) and single-cell transcriptomic data (GSE149512).
• Performed single-sample gene set enrichment analysis (ssGSEA) for immune cell proliferation.
• Applied Seurat for single-cell analysis, limma for differential gene expression, WGCNA for module identification, and LASSO/SVM-RFE for biomarker selection.
• Verified key genes using real-time quantitative polymerase chain reaction (RT-qPCR).

Main Results:

• Identified C9orf72 and CRTAP as hub genes for NOA with high diagnostic potential (AUCs 0.861 and 0.917, respectively).
• RT-qPCR confirmed the critical expression of C9orf72 and CRTAP in NOA samples.
• Macrophage infiltration was found to be significant across different NOA subtypes.

Conclusions:

• Macrophage infiltration plays a significant role in various subtypes of non-obstructive azoospermia.
• C9orf72 and CRTAP are hypothesized to be critical in NOA due to their high expression in macrophages.
• These genes represent potential diagnostic biomarkers for non-obstructive azoospermia.