GutMGene-Guided Peripheral Blood Transcriptomics Identifies an FLNA-Associated Host-Gene Signal in Diabetic Retinopathy.

Diabetic retinopathy (DR) reflects retinal microvascular injury and systemic immune-metabolic stress, and most public DR transcriptomic datasets lack paired microbiome/metabolomic profiles. We used gutMGene v2.0 as a curated microbe/metabolite-host gene prior and integrated it with peripheral blood transcriptomics from GSE221521. Candidate genes were refined by weighted gene co-expression network analysis (WGCNA), repeated resampling, cross-dataset assessment, mechanism scoring, peripheral blood mononuclear cell (PBMC) single-cell localization and filamin A (FLNA)-centered single-cell gene regulatory network (GRN) virtual knockout. The gutMGene prior contained 238 host genes; 15 DR-associated genes overlapped this prior, and WGCNA retained ten candidate gut microbe and microbial metabolite-related genes (GMMRGs): FLNA, AKT1, IRAK1, BCL10, CDK6, CTSD, JUP, CXCL1, CXCR2 and IL4R. Resampling prioritized FLNA as the most consistent candidate. Cross-dataset assessment localized the strongest signal to type 2 diabetes (T2D) PBMCs, retinal endothelial cells and advanced proliferative diabetic retinopathy with diabetic macular edema (PDR + DME) retinal tissue, with weaker separation in whole blood, broad retinal tissue and six-donor type 1 diabetes (T1D) PBMCs. FLNA virtual knockout predicted cell-context-dependent perturbation of immune-related transcriptional programs, including IL4R in DR B cells and CTSD in DR monocytes/NK cells. This prior-guided study identifies FLNA within a ten-gene GMMRG set as a circulating host-response signal that links curated microbe/metabolite-host records to immune-vascular and cytoskeletal remodeling in DR.