Time-course analysis of coproantigens in rats infected and challenged with Fasciola hepatica

Abstract

The influence of a challenge infection during an acute or chronic primary infection on Fasciola hepatica-coproantigen kinetics was established in rats. Egg-output and IgG humoral responses were also established. Two primary-infected groups were reinfected at different periods, one 4 weeks after primary infection (w.p.i.) (acute phase) and the other 11 w.p.i. (chronic phase). Another group remained without reinfection as a control. Coproantigens were first detected in the group challenged on acute fascioliasis. The highest values of coproantigens were recorded in the group reinfected during acute fascioliasis and the lowest in the group challenged during chronic fascioliasis. The IgG responses to F. hepatica excretory/secretory antigens increased after reinfection. Neither the egg output nor the parasitic burden were significantly different among the three infected groups. Our results indicate that the time of challenge affects the kinetics of coproantigens. Thus, challenge during acute fascioliasis favours the migration of the juvenile flukes from the primary infection to the bile ducts, and is responsible for the earlier presence of coproantigens in these animals. The possible relationship between coproantigen detection and T1 and T2 tegumentary antigens is discussed.

Fasciola hepatica reinfection potentiates a mixed Th1/Th2/Th17/Treg response and correlates with the clinical phenotypes of anemia

“…Also, it is accepted that primary infections cause partial protection against a secondary reinfection in some rat strains, the so-called concomitant immunity [61–63], which is the reason why rats are presently not used in models of experimental reinfection. Fasciola reinfection was confirmed in Wistar rat/ F .…”

Diagnosis of human fascioliasis by stool and blood techniques: update for the present global scenario

“…Antigen detection tests usually use antigen-capture assays, although other systems have been described. The first tests were designed using polyclonal antibodies (Langley and Hillyer, 1989 a , b ; Rodríguez-Pérez and Hillyer, 1995; Sanchez-Andrade et al 2000, 2001; Almazan et al 2001; Paz-Silva et al 2002), and later monoclonal antibodies (MoAb) as they are more specific than polyclonal antibodies for antigen capturing, i.e. they permit the detection of well-defined epitopes.…”

Prevalence of natural ovine fasciolosis shown by demonstrating the presence of serum circulating antigens

“…Several investigations (Rodrı´-guez-Pe´rez and Hillyer 1995;Dume´nigo et al 1996;Espino et al 1997;Abdel-Rahman et al 1998;Sa´n-chez-Andrade et al 2001;Paz-Silva et al 2002) have proved the suitability of the direct-enzyme-linked immunosorbent assay (ELISA) for a feasible and correct diagnostics of fasciolosis in serum or faecal samples. Dume´nigo et al (1999) and Almaza´n et al (2001) proved that in ovine experimental fasciolosis, antigenaemia was detected 1 week after infection, whereas positive antibody values were obtained from the second week after infection.…”