A pore-forming haemolysin from the hookworm, Ancylostoma caninum

Don, T. A., Jones, M. K., Smyth, D. , O'Donoghue, P., Hotez, P. and Loukas, A. (2004) A pore-forming haemolysin from the hookworm, Ancylostoma caninum. International Journal for Parasitology, 34(9), pp. 1029-1035. (doi: 10.1016/j.ijpara.2004.04.013) (PMID:15313129)

Abstract

Hookworms feed on blood, but the mechanism by which they lyse ingested erythrocytes is unknown. Here we show that Ancylostoma caninum, the common dog hookworm, expresses a detergent soluble, haemolytic factor. Activity was identified in both adult and larval stages, was heat-stable and unaffected by the addition of protease inhibitors, metal ions, chelators and reducing agents. Trypsin ablated lysis indicating that the haemolysin is a protein. A closely migrating doublet of hookworm proteins with apparent molecular weights of 60–65 kDa bound to the erythrocyte membrane after lysis of cells using both unlabeled and biotinylated detergent-solubilised hookworm extracts. In addition, separation of detergent-soluble parasite extracts using strong cation-exchange chromatography, resulted in purification of 60–65 kDa proteins with trypsin-sensitive haemolytic activity. Erythrocytes lysed with particulate, buffer-insoluble worm extracts were observed using scanning electron microscopy and appeared as red cell ghosts with approximately 100 nm diameter pores formed in the cell membranes. Red blood cell ghosts remained visible indicating that lysis was likely caused by pore formation and followed by osmotic disruption of the cell.

• Item Type: Articles
• Additional Information: This research was funded by a block grant awarded to QIMR by the National Health and Medical Research Council of Australia (NHMRC), a grant from the Ramaciotti Foundation and a grant from the Bill and Melinda Gates Foundation awarded to the Sabin Vaccine Institute and P.J.H. T.D. was supported by a postgraduate award from QIMR and an Australian Postgraduate Award. A.L. is an NHMRC R. Douglas Wright fellow.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Smyth, Dr Danielle
• Authors: Don, T. A., Jones, M. K., Smyth, D., O'Donoghue, P., Hotez, P., and Loukas, A.
• College/School: College of Medical Veterinary and Life Sciences > School of Infection & Immunity
• Journal Name: International Journal for Parasitology
• Publisher: Elsevier
• ISSN: 0020-7519
• ISSN (Online): 1879-0135
• Published Online: 09 June 2004