Xth ICT, August 2000

Ultrastructural characteristics of nurse cell-larva complex of four species of Trichinella in several hosts

¹ Department of Animal Biology, University of Pavia, Pavia, Italy.
² Canadian Food Inspection Agency, Saskatoon, Saskatchewan, Canada S7N 2R3.
³ Istituto Superiore di Sanità, Rome, Italy.

^* Correspondence : E. Pozio. Istituto Superiore di Sanità, viale Regina Elena 299, 00161 Rome, Italy. Tel.: +39 06 4990 2304 - Fax : +39 06 4938 7065. - E-mail : pozio@iss.it

Abstract

The nurse cell-larva complex of nematodes of the genus Trichinella plays an Important role in the survival of the larva in decaying muscles, frequently favouring the transmission of the parasite in extreme environmental conditions. The ultrastructure of the nurse cell-larva complex in muscles from different hosts infected with T. nativa (a walrus and a polar bear), T. spiralis (horses and humans), T. pseudospiralis (a laboratory mouse) and T. papuae (a laboratory mouse) were examined. Analysis with transmission electron microscope showed that the typical nurse cell structure was present in all examined samples, irrespective of the species of larva, of the presence of a collagen capsule, of the age of infection and of the host species, suggesting that there exists a molecular mechanism that in the first stage of larva invasion is similar for encapsulated and non-encapsulated species.