a1 Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, 04510 México D.F.
In previous studies, ultrastructural observations revealed a large number of gap junctions (GJs) in the neck and immature proglottid tissues of Taenia solium tapeworms. In these helminths, cytoplasmic glycogen sacs are connected by numerous discrete GJs to other cells throughout the maturing strobilar tissue. Discontinuous sucrose gradients were used to purify membrane fractions containing GJs, which were identified by ultrastructural analysis. A trans-membrane peptide sequence from a highly conserved innexin region was used to construct a 20-amino acid synthetic peptide and used to raise polyclonal antibodies in rabbits that recognized both a 55 and a 67 kDa protein in a Western blot of the GJ-enriched pellet. Immunohistochemistry of larval and adult worm sections incubated with antiserum to the synthetic peptide and a secondary anti-rabbit IgG bound to fluorescein, revealed strong binding to the tegumentary surface of the worm, as well as patchy fluorescent areas in the parenchyma. The results indicate that both the tegument of cysticerci and adult T. solium contain innexin-rich membranes, which may function as a tegumentary transport system for small molecules.
(Received March 18 2008)
(Revised April 14 2008)
(Revised April 30 2008)
(Accepted May 01 2008)
(Online publication July 14 2008)
c1 Corresponding author: Departamento de Microbiología y Parasitología, Facultad de Medicina, UNAM, Edificio A, Primer Piso, Ciudad Universitaria, México 04510, D.F. México. Tel: +5255 5623 2356/87. Fax. +5255 5623 2382. E-mail: email@example.com