Taenia solium cysticercosis, a parasitic disease that affects human health in 41 various regions of the world, is preventable by vaccination. Both the 97-amino42 acid-long KETc7 peptide and its carboxyl-terminal, 18-amino-acid-long sequence 43 (GK-1) are found in Taenia crassiceps. Both peptides, with proven protective 44 capacity against cysticercosis, are part of the highly conserved, cestode-native, 45 264-amino-acid long protein KE7. KE7 belongs to a ubiquitously distributed family 46 of proteins associated to membrane processes and may participate in several vital 47 cell pathways. 48 This study is aimed to identify the T. solium KE7 (TsKE7) full-length protein 49 and to determine its immunogenic propertie... More
Taenia solium cysticercosis, a parasitic disease that affects human health in 41 various regions of the world, is preventable by vaccination. Both the 97-amino42 acid-long KETc7 peptide and its carboxyl-terminal, 18-amino-acid-long sequence 43 (GK-1) are found in Taenia crassiceps. Both peptides, with proven protective 44 capacity against cysticercosis, are part of the highly conserved, cestode-native, 45 264-amino-acid long protein KE7. KE7 belongs to a ubiquitously distributed family 46 of proteins associated to membrane processes and may participate in several vital 47 cell pathways. 48 This study is aimed to identify the T. solium KE7 (TsKE7) full-length protein 49 and to determine its immunogenic properties. TsKE7 was recombinantly expressed 50 in Escherichia coli Rosetta 2 (rTsKE7) and used to obtain mouse polyclonal 51 antibodies. Anti-rTsKE7 antibodies detected the expected native protein among the 52 350 spots developed from T. solium cyst vesicular fluid in a mass spectrometry53 coupled immune-proteomic analysis. These Abs were then used to screen a 54 phage-displayed 7-random peptide library to map B-cell epitopes. The recognized 55 phages displayed 9 peptides with the consensus motif YF/YPS sequence, which 56 includes YYYPS (named GK-1M for being a GK-1 mimotope), exactly matching a 57 part of GK-1. GK-1M was recognized by 58% of sera from cysticercotic pigs with 58 100% of specificity, but induced a weak protection against murine cysticercosis. 59 In silico analysis revealed universal T cell epitope(s) in nTsKE7, potentially 60 capable of stimulating CTL and helper T lymphocytes under different MHC class I 61 and class II mouse haplotypes
