Apolipoprotein A-I As a Molecular Target of the Immunomodulatory Peptide Jusvinza: Mechanistic Insights from Affinity and in Silico Studies.

Jusvinza is an immunomodulatory pharmaceutical drug developed for the treatment of rheumatoid arthritis. Its active ingredient is an altered peptide ligand-derived from a T-cell epitope of the human 60-kDa heat shock protein-referred to as CIGB-814. Jusvinza has also proven effective in reducing hyperinflammation in COVID-19. However, molecular targets of CIGB-814 in patients remain undefined, and this study is aimed at identifying specific plasma proteins that interact with CIGB-814. Affinity chromatography and mass spectrometry analysis revealed apolipoprotein A-I as a CIGB-814-binding partner. Interestingly, no apolipoprotein A-I bands were detected in the affinity matrix of the wild-type peptide (designated as E18-3). In this context, it was relevant to analyze how the substitution of Asp18 with Leu-used to design CIGB-814 from the wild-type peptide-confers its ability to bind apolipoprotein A-I. Docking studies predicted the N-terminal domain of apolipoprotein A-I as the most likely region for peptide interaction and suggested a strong connection between CIGB-814 and apolipoprotein A-I. Further validation by molecular dynamics simulations suggests that CIGB-814 may enhance the flexibility of structural areas in apolipoprotein A-I critical for high-density lipoproteins assembly. Additionally, an affinity enzyme-linked immunosorbent assay (ELISA) confirmed that apolipoprotein A-I has a tenfold greater affinity for CIGB-814 compared to the wild-type peptide. These integrated experimental and computational findings demonstrate that a single residue substitution is critical for apolipoprotein A-I recognition. In addition, this study provides mechanistic insight into CIGB-814 immunomodulatory and metabolic effects, expanding the therapeutic potential of Jusvinza to metabolic diseases associated with lipid homeostasis imbalance.