ORIGINAL PAPERW. Zhang Æ E. Moreau Æ F. Peigne´ Æ W. HuangA. ChauvinComparison of modulation of sheep, mouse and buffalo lymphocyteresponses by Fasciola hepatica and Fasciola giganticaexcretory-secretory productsReceived: 14 December 2004/ Accepted: 22 December 2004/Published online: 12 February 2005? Springer-Verlag 2005Abstract In order to explain the dif f erence in suscepti-bility to Fasciola hepatica and F. gigantica betweenanimal species, the activity of their excretory-secretoryproducts (FhESP and FgESP, respectively) on conca-navalin A (ConA)-induced proliferation of dif f erentanimal species (sheep, mouse and buf f alo) lymphocyteswas compared. At high doses, FhESP inhibited prolif-eration of lymphocytes of all the animal species tested,and at low doses they inhibited the proliferation of sheeplymphocytes and increased the proliferation of buf f aloand mouse lymphocytes. The ef f ects of FgESP weresimilar but the intensity of FgESP inhibition was lessthan FhESP. The immunomodulatory ef f ects of FhESPor FgESP could not alone explain the susceptibility levelof hosts to Fasciola spp. The immunomodulatory mol-ecules of FhESP and FgESP and their role in the courseof Fasciola spp. infection should be further investigated.IntroductionFasciolosis is a parasitic disease that causes considerableeconomic losses in ruminants. Animals like sheep andbuf f aloes could be infected by Fasciola gigantica or byF. hepatica, but dif f erences in susceptibility to theseparasites have been described: buf f aloes are susceptibleto F. gigantica infection but are less susceptible toF. hepatica infection (Yadav et al. 1999; Chen et al.2000), while certain breeds of sheep, like IndonesianThin Tail (ITT) or Belle Ilois sheep (Roberts et al. 1997;Zhang et al. 2004), are susceptible to F. hepatica infec-tion but are less susceptible to F. gigantica.A comparison of humoral responses of Belle Iloissheep against F. gigantica and F. hepatica showed thatthe recognition of the higher molecular mass antigens byF. gigantica-infected sheep and not by F. hepatica-in-fected sheep could be associated with the resistanceobserved during F. gigantica infection (Zhang et al.2004). Futhermore, the dif f erence in the susceptibility ofITT sheep to F. hepatica and F. gigantica could beexplained by the fact that F. hepatica immature para-sites, and not F. gigantica, have an ef f ective defenceagainst the superoxide-dependent killing mechanisms ofmacrophages or eosinophils from ITT sheep (Meeusenand Piedraf i ta 2003).These previous results suggest that the dif f erent sus-ceptibility of hosts to F. hepatica or to F. giganticainfection is not only associated with dif f erent host im-mune responses but also with the capacity of the para-sites to evade host immunity. The present study wasdesigned to compare the immunomodulatory ef f ect ofF. gigantica excretory-secretory products (FgESP) andF. hepatica excretory-secretory products (FhESP) onlymphocytes of sheep, mice (the laboratory experimentalanimal model of sheep F. hepatica infection) andbuf f aloes.Materials and methodsAnimalsA total of 30 2-month old male Balb/c mice (Janvier,France) were used for the experiments.Five Belle Ilois sheep and f i ve cross-bred buf f aloes ofthe Murrha and swamp type of Guangxi (China),approximatively 12 months old were used throughout.W. Zhang Æ E. Moreau (&) Æ F. Peigne´ Æ A. ChauvinUMR INRA/ENVN Interactions Hoˆ te-Parasite-Milieu,Ecole Nationale Ve´ te´ rinaire de Nantes,BP 40706, 44307 Nantes Cedex 03, FranceE-mail: moreau@vet-nantes.frTel.: +33-2-40687705Fax: +33-2-40687694W. Zhang Æ W. HuangCollege of Animal Science and Technology,Guangxi University, 530005 Nanning, ChinaParasitol Res (2005) 95: 333–338DOI 10.1007/s00436-005-1306-x
