title: I-domain-antigen conjugate (IDAC) for delivering antigenic peptides to APC: synthesis, characterization, and in vivo EAE suppression.
abstract: The objectives of this work are to characterize the identity of I-domain-antigen conjugate (IDAC) and to evaluate the in vivo efficacy of IDAC in suppressing experimental autoimmune encephalomyelitis (EAE) in mouse model. The hypothesis is that the I-domain delivers PLP(139-151) peptides to antigen-presenting cells (APC) and alters the immune system by simultaneously binding to ICAM-1 and MHC-II, blocking immunological synapse formation. IDAC was synthesized by derivatizing the lysine residues with maleimide groups followed by conjugation with PLP-Cys-OH peptide. Conjugation with PLP peptide does not alter the secondary structure of the protein as determined by CD. IDAC suppresses the progression of EAE, while I-domain and GMB-I-domain could only delay the onset of EAE. As a positive control, Ac-PLP-BPI-NH(2)-2 can effectively suppress the progress of EAE. The number of conjugation sites and the sites of conjugations in IDAC were determined using tryptic digest followed by LC-MS analysis. In conclusion, conjugation of I-domain with an antigenic peptide (PLP) resulted in an active molecule to suppress EAE in vivo.
authors.affiliation: Department of Pharmaceutical Chemistry, University of Kansas, Lawrence, Kansas 66047, USA.
authors.forename: Prakash
authors.initials: P
authors.lastname: Manikwar
authors.forename: Barlas
authors.initials: B
authors.lastname: Büyüktimkin
authors.forename: Paul
authors.initials: P
authors.lastname: Kiptoo
authors.forename: Ahmed H
authors.initials: AH
authors.lastname: Badawi
authors.forename: Nadezhda A
authors.initials: NA
authors.lastname: Galeva
authors.forename: Todd D
authors.initials: TD
authors.lastname: Williams
authors.forename: Teruna J
authors.initials: TJ
authors.lastname: Siahaan
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000941:Antigens / Q000008:administration & dosage*; D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D004681:Encephalomyelitis, Autoimmune, Experimental / Q000517:prevention & control*; D005260:Female; D051379:Mice; D008815:Mice, Inbred Strains; D008969:Molecular Sequence Data; D010455:Peptides / Q000008:administration & dosage*; D021241:Spectrometry, Mass, Electrospray Ionization; D014961:X-Ray Diffraction
chemical_list: D000941:Antigens; D010455:Peptides