Predicción de unión de péptidos de MSP-1 y EBA-140 de Plasmodium falciparum al HLA clase II

The MSP-1 merozoite surface protein is related to the invasion phenomenon of malaria to red cells, while the EBA-140 antigen protein interacts with the sialoglycoproteins on the surface of erythrocytes. The identification of peptides from both proteins that bind to HLA class II has a particular importance for the development of vaccines.

In the present work, a predictive binding to HLA class II theory, based on S/k proportion of entropy was applied, for the prediction of proteins MSP-1 and EBA-140 binding phenomenon to the totality of 20 amino acid sequences of both molecules. The probability, combinatory and entropy values were calculated for 948 and 732 nonamer overlapping sequences of MSP-1 and EBA-140, respectively. Three theoretical proteins of 500 aminoacids of lenght each were computationally built in order to apply the developed binding theory to all their nonamer overlapping peptides.

It was predicted that for the two studied merozoite proteins, 298 sequences are related to the binding macrostate and 1409 to the not-binding macrostate. The developed theoretical prediction can facilitate the selection of peptides during the process of vaccine development. For the three theoretical proteins built, it was found that 111, 84 and 72 are predicted as included into the binding macrostate, while sequences 381, 408, and 420 are predicted as related to the not-binding macrostate.

The predictions are an evidence of a physical and mathematical order in antigen presentation, which can be useful to the development of vaccines.