Identification of Biomarker in Ankylosing Spondylitis via Multi-Chip Integration Analysis of Gene Differential Expression.

Background: Ankylosing spondylitis (AS) is a chronic inflammatory autoimmune disease that affects axial joints such as the spine. Early diagnosis is essential to improve treatment outcomes. The purpose of this study is to uncover underlying genetic diagnostic features of AS.

Methods: We downloaded gene expression data from the Gene Expression Omnibus (GEO) database for three studies of groups of healthy and AS samples. After preprocessing and normalizing the data, we employed linear models to identify significant differentially expressed genes (DEGs) and further integrated the differential genes to acquire reliable differential transcriptional markers. Gene functional enrichment analysis was conducted to obtain enriched pathways and regulatory gene interactions were extracted from pathways to further elucidate pathway networks. Seventy-three reliably differentially expressed genes (DEGs) were integrated by differential analysis. Utilizing the regulatory relationships of the 21 Kyoto Encyclopedia of Genes and Genomes (KEGG) Pathway genes that were enriched in the analysis, a regulatory network of 622 genes was constructed and its topological properties were further analyzed.

Results: Functional enrichment analysis found 73 DEGs that were strongly associated with immune pathways like Th17, Th1 and Th2 cell differentiation. Using KEGG combined with DEGs, six hub genes (, , , , , and ) were suggested from the network. Of these, the gene was significantly differentially expressed compared with the normal control.

Conclusion: (Interleukin-2 receptor beta) is strongly associated with the onset and progression of autoimmune joint diseases, and may be used as a potential biomarker of AS. This study offers new characteristics that can help in the diagnosis and individualized therapy of AS.