Changing ABRA protein peptide to fit into the HLA-DRbeta1*0301 molecule renders it protection-inducing.
Salazar, L.M., Alba, M.P., Curtidor, H., Bermudez, A., Vargas, L.E., Rivera, Z.J., Patarroyo, M.E.(2004) Biochem Biophys Res Commun 322: 119-125
- PubMed: 15313182 
- DOI: https://doi.org/10.1016/j.bbrc.2004.07.086
- Primary Citation of Related Structures:  
2MU9 - PubMed Abstract: 
The Plasmodium falciparum acidic-basic repeat antigen represents a potential malarial vaccine candidate. One of this protein's high activity binding peptides, named 2150 ((161)KMNMLKENVDYIQKNQNLFK(180)), is conserved, non-immunogenic, and non-protection-inducing. Analogue peptides whose critical binding residues (in bold) were replaced by amino-acids having similar mass but different charge were synthesized and tested to try to modify such immunological properties. These analogues' HLA-DRbeta1* molecule binding ability were also studied in an attempt to explain their biological mechanisms and correlate binding capacity and immunological function with their three-dimensional structure determined by (1)H NMR. A 3(10) distorted helical structure was identified in protective and immunogenic peptide 24922 whilst alpha-helical structure was found for non-immunogenic, non-protective peptides having differences in alpha-helical position. The changes performed on immunogenic, protection-inducing peptide 24922 allowed it to bind specifically to the HLA-DRbeta1*0301 molecule, suggesting that these changes may lead to better interaction with the MHC Class II-peptide-TCR complex rendering it immunogenic and protective, thus suggesting a new way of developing multi-component, sub-unit-based anti-malarial vaccines.
Organizational Affiliation: 
Fundación Instituto de Inmunologia de Colombia (FIDIC), Cra 50 No. 26-00, Bogota, Colombia.