Characterization of a Trypanosoma cruzi antigen with homology to intracellular mammalian lectins

Int J Parasitol. 2006 Dec;36(14):1473-84. doi: 10.1016/j.ijpara.2006.08.010. Epub 2006 Sep 20.

Abstract

Two cDNAs, isolated from a Trypanosoma cruzi amastigote library immunoscreened with sera from patients with Chagas disease, encode proteins with sequence homology to eukaryotic components of the cellular sorting and recycling machinery. These proteins, denominated TcAGL, present an N-terminal lectin domain and a C-terminal region containing repetitive amino acids and a poly-glutamine tract. They are products of polymorphic alleles of a single copy gene constitutively expressed during the parasite life cycle. Polyclonal antibodies obtained from mice immunized with the recombinant antigen recognize proteins with apparent molecular weight ranging from 95 to 120 kDa in cell lysates from all three life stages and in various strains of the parasite. Sera from Chagas disease patients recognize the recombinant antigen in ELISA and immunoprecipitation assays but not in Western blot assays under denaturing conditions. Consistent with its proposed role in the glycoprotein secreting pathway, immunofluorescence analyses and expression of a green fluorescent protein-tagged TcAGL protein indicate a sub-cellular localization in the vicinity of the flagellar pocket membrane and the Golgi complex of the parasite.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Antigens, Protozoan / immunology*
  • Base Sequence
  • Chagas Disease / immunology*
  • DNA, Circular / immunology
  • DNA, Protozoan / immunology
  • Fluorescent Antibody Technique, Indirect / methods
  • Humans
  • Lectins / immunology*
  • Mice
  • Microscopy, Fluorescence / methods
  • Molecular Sequence Data
  • Molecular Weight
  • Nuclear Envelope / immunology
  • Protozoan Proteins / immunology
  • RNA, Messenger / analysis
  • RNA, Protozoan / analysis
  • Recombinant Fusion Proteins / immunology
  • Sequence Homology, Nucleic Acid
  • Trypanosoma cruzi / immunology*

Substances

  • Antigens, Protozoan
  • DNA, Circular
  • DNA, Protozoan
  • Lectins
  • Protozoan Proteins
  • RNA, Messenger
  • RNA, Protozoan
  • Recombinant Fusion Proteins

Associated data

  • GENBANK/AY013869
  • GENBANK/DQ438980