摘要Background:The previous research has confirmed the existence of idiosyncratic drug-induced liver injury(IDILI)caused by Polygonum multiflorum(PM-IDILI),and demonstrated that PM-IDILI is an immune-mediated injury,with HLA-B*35:01 identified as a genetic suscep-tibility marker.Additionally,emodin-8-O-β-D-glucoside(EG)and 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside have been pro-posed as potential contributory ingredients in the pathogenesis of PM-IDILI.However,the precise mechanisms through which these susceptible factors contribute to the development of PM-IDILI remain unclear.Objectives:This study aims to explore the molecular characteristics of HLA-B*35:01 that contribute to PM-DILI and to propose a mechanistic hypothesis based on our previous research on PM-induced protein adducts.Methods:Key differences between HLA-B*35:01 and general Chinese HLA-B alleles were identified by comparing protein sequences,peptide binding motifs,and protein structures.Molecular docking was employed to assess whether PM-induced haptenated peptides can be presented by HLA-B*35:01 and other related alleles.Additionally,a simplified dipeptide model was used to evaluate the binding affinity of HLA-B*35:01 to EG-haptenated peptides.Results:Our findings revealed significant differences in the residues of the B and F peptide binding pockets of HLA-B*35:01 compared to general Chinese HLA-B alleles.Further analysis suggested that the F pocket of HLA-B*35:01 was capable of binding EG-cysteine adducts and might be a key feature in the PM-IDILI pathogenesis.Peptide docking using DINC and molecular dynamics simulations indicated that HLA-B*35:01 could form stable complexes with EG-haptenated peptides.Molecular dynamics simulations also highlighted the critical roles of both the B and F pockets in peptide binding.Specifically,the F pocket binds the EG-modified residue in haptenated peptides,while the B pocket,despite lacking shared features among PM-IDILI patients,may indirectly influence the inci-dence of PM-IDILI by filtering haptenated peptides.The binding affinity of HLA-B*35:01 to EG-modified cysteine residues was experi-mentally validated through a dipeptide-based assay,confirming that HLA-B*35:01 could bind EG-haptenated peptides.Conclusions:This study identified the unique B and F binding pockets of HLA-B*35:01 as key factors in PM-IDILI pathogenesis and demonstrated that HLA-B*35:01 could bind EG-haptenated peptides.These findings suggest that PM-IDILI may be a hapten-based drug hypersensitivity reaction driven by EG,providing a theoretical framework for further research aimed at elucidating the molecular mechanisms underlying PM-IDILI.