Rabbit serum against K1 peptide, an immunogenic epitope of the Trypanosoma cruzi KMP-11, decreases parasite invasion to cells

► Polyclonal antibodies rose against K1 peptide recognized the native KMP-11 protein on T. cruzi. ► Anti-K1 antibodies inhibited the invasion of T. cruzi trypomastigotes to eukaryotic cells. ► Bioinformatics indicated that some amino acid residues of K1 are accessible for antibody binding.