Identifying the potential therapeutic targets of tertiary lymphoid structure in IgA nephropathy based on bioinformatics

Studies have found that there is tertiary lymphoid structure (TLS) in IgA nephropathy (IgAN), and the existence of TLS has an impact on renal function, creatinine, and proteinuria in patients. We aim to explore the potential molecular mechanisms and therapeutic targets of TLS in IgA nephropathy by bioinformatics methods, hoping to provide treatment methods. The datasets GSE226840, GSE237120, and GSE116626 from the Gene Expression Omnibus (GEO) database were employed to investigate the potential therapeutic targets of TLS in IgAN. The R was used to obtain the differentially expressed genes (DEGs) of three datasets, and the Venny was used to intersect the above three parts of the DEGs to obtain the common DEGs. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed on obtained genes using Metascape. Protein-Protein interaction (PPI) network was constructed. The intersection of the above common differential genes and IgAN differential genes was obtained by Venny tool. The Nephroseq platform was used to screen core genes and explore their relationship with clinical features. Meanwhile, CIBERSORT was utilized to further delve into the correlation between core genes and immune cells. 92 TLS-related genes and 486 IgAN related genes were obtained, and 6 common genes were obtained after crossing the two genes. The intersection genes were verified by Nephroseq, and CDKN1A, CD83, DUSP6, and CD48 were identified as core genes. At the same time, there were differences in the composition of immune cells between the disease group and the control group when the immune infiltration analysis was performed. And by further analyzing the correlation between core genes and immune cells, the study found that the four genes were positively correlated with T cells, B cells, plasma cells, and other immune cells. By exploring the relationship between core genes and clinical features, CDKN1A and DUSP6 were negatively correlated with Glomerular Filtration Rate (GFR) and positively correlated with proteinuria in IgAN patients. CD48 was negatively correlated with GFR and positively correlated with Blood Urea Nitrogen (BUN). The four genes highly associated with TLS and IgAN were screened using GEO database in study. And CDKN1A, CD83, DUSP6 and CD48 may provide potential therapeutic targets for the treatment of TLS in IgAN. At the same time, studies have found that T cells, B cells, and macrophages may be involved in the formation of TLS in IgAN.