Jornal de Técnicas Imunológicas e Doenças Infecciosas

Epitope Mapping of a Long Peptide Candidate for Diagnosis of Hepatitis C - Evaluation of the Antigenicity by the Multiple Antigen Blot Assay (MABA)

Henry B, Adriana G, Marilyan T, Angelita LM, Sandra L, Daniel AL, Nahir M, Pierina DA, Doneyla S and Oscar N

Epitope Mapping of a Long Peptide Candidate for Diagnosis of Hepatitis C - Evaluation of the Antigenicity by the Multiple Antigen Blot Assay (MABA)

Hepatitis C is a worldwide public health problem by its high prevalence and relevance and the impact in the high incidence of liver cirrhosis and liver cancer. Previous studies identified the peptide IMT-286 (40 mer), located in the core of the virus as a possible candidate to be used in the diagnosis of Hepatitis C by ELISA. The synthesis of long peptides in addition to its higher cost may be limited by undesirable reactions (cycling, deletions, etc.) that impede the synthesis. Therefore, we decided to reduce its size by selecting the potential epitopes of this sequence, whether corresponded to continuous or discontinuous primary sequences. For this, different peptide sequences were synthesized and evaluated for their antigenicity (SPOT mapping) by the pep scan strategy. Two peptides of Core antigen showed the highest sensitivities, peptide IMT-1700 (26 mer), located in the central region, presented a 59.09% recognition by sera from infected patients by the Multiple Antigen Blot Assay (MABA), while the IMT-286 (40 mer) peptide showed a recognition of 70.45 % The alkaline phosphatase conjugate showed a better sensitivity than the peroxidase conjugate with Luminol® as a substrate by MABA.