Vet. Res. 36 (2005) 1-12
DOI: 10.1051/vetres:2004047

Phenotype of hepatic infiltrates and hepatic lymph nodes of lambs primarily and challenge infected with Fasciola hepatica, with and without triclabendazole treatment

José Pérez^a, Joaquín Ortega^b, Ana Bravo^c, Pablo Díez-Baños^d, Patrocinio Morrondo^d, Teodoro Moreno^e and Alvaro Martínez-Moreno<sup>e

a</sup>  Departamento de Anatomía y Anatomía Patológica Comparadas, Edificio de Sanidad Animal, Campus de Rabanales, Ctra, Madrid-Cádiz, Km 396, 14014 Córdoba, Spain
^b  Departamento de Sanidad Humana y Animal, Facultad de Ciencias Experimentales y de la Salud Universidad Cardenal Herrera-CEU Valencia, Spain
^c  Unidad Docente de Anatomía Patológica Veterinaria, Departamento de Patología Animal, Facultad de Veterinaria de Lugo, Universidad de Santiago de Compostela, Spain
^d  Cátedra de Parasitología y Enfermedades Parasitarias, Departamento de Patología Animal, Facultad de Veterinaria de Lugo, Universidad de Santiago de Compostela, Spain
^e  Cátedra de Parasitología, Departamento de Sanidad Animal, Facultad de Veterinaria de Córdoba, Spain

(Received 29 January 2004; accepted 9 June 2004)

Abstract - The phenotype of the hepatic inflammatory infiltrate and hepatic lymph nodes (HLN) was analysed in lambs primarily and challenge infected with Fasciola hepatica. Group 1 was primarily and challenge infected with two doses of 200 metacercariae (mc) each and was non-treated. Trickle infection was administered to five groups: group 2 was challenge infected and non-treated; group 3 was primarily infected and non-treated; group 4 was primarily infected and treated with triclabendazole (TCBZ) at 12 weeks postinfection (wpi); group 5 was treated at 4 wpi and challenge infected and group 6 was treated at 12 wpi and challenge infected. An uninfected group was used as the control. The distribution of T cell subpopulations (CD3, CD4 and CD8), and B cells (CD79 , IgM, IgG) was analysed. The hepatic inflammatory infiltrate was represented mainly by CD3 and CD4 T cells, and B cells (CD79 , IgG). These infiltrates were more severe (P < 0.05) in primarily (group 3) or challenge (groups 2, 5 and 6) trickle infected lambs than in the group single challenge infected (group 1). Cellular changes in HLN consisted in an increase of CD4 over CD8 T cells and an increase of B cells and IgG⁺ plasma cells, and they were more severe in primarily and challenge trickle infected groups than in the group infected with two larger doses of mc, although significant differences were not found with respect to all challenge trickle infected groups. The strong local cellular and humoral immune responses did not protect against subsequent infections, neither in non-treated lambs (group 2) nor in lambs treated with TCBZ at 4 wpi (group 5) or 12 wpi (group 6).

Key words: Fasciola hepatica / sheep / immune response / lymphocyte subsets / triclabendazole

Corresponding author: José Pérez an1pearj@uco.es

© INRA, EDP Sciences 2005