C5AR1 and type 2 diabetes mellitus: Bioinformatics and transcriptomic analyses have identified five key hub genes including TLR4, ITGAM (Integrin alpha M), C5AR1 (Complement component 5a receptor 1), FCER1G (High affinity immunoglobulin epsilon receptor subunit gamma), and FCGR2A (Fc gamma receptor IIA) that are upregulated in both H. pylori infection and T2DM, suggesting these genes mediate shared inflammatory and immune pathways implicated in disease progression [147,148].