Short communication Cellular and humoral responses in liver of cattle and buffaloes infected with a single dose of Fasciola gigantica Elizabeth C. Molina a,b, * , Lee F. Skerratt b a College of Veterinary Medicine, University of Southern Mindanao, Kabacan, Cotabato 9407, Philippines b School of Tropical Veterinary and Biomedical Sciences, James Cook University, Townsville, Qld 4811, Australia Received 4 February 2005; received in revised form 22 April 2005; accepted 27 April 2005 Abstract The cellular components of the hepatic inflammatory infiltrate in cattle and buffaloes infected with a single dose of 1000 Fasciola gigantica were analysed by immunohistochemistry and histology. T and B lymphocytes, plasma cells, eosinophils and mast cells were present in the hepatic lesions. It is proposed that both cellular and humoral immune responses were induced in the liver of cattle and buffaloes during infection with F. gigantica probably by antigens released by the developing flukes and by damage caused by the flukes during their migration in the liver. The local T cell response differed between these animals, with the response decreasing after 3 weeks post-infection in cattle in contrast to a gradually increasing response in buffaloes. Difference in the T cell response between cattle and buffaloes may be related to their differences in resistance and resilience to infection with F. gigantica. # 2005 Elsevier B.V. All rights reserved. Keywords: Fasciola gigantica; Cattle; Buffaloes; Immune response; Liver Fasciolosis caused by Fasciola gigantica is an economically important disease among cattle and buffaloes in the tropics. To date, only few studies have been reported regarding the pathogenesis of infection with F. gigantica in these animals and there is no description of the cellular and humoral responses in hepatic lesions in cattle and swamp buffaloes infected with F. gigantica. Such information will provide an indication of the local immune response of infected animals and give additional insight regarding the pathogenesis of F. gigantica infection in these species. In F. hepatica infections, cell-mediated immune response has been described in terms of in vitro proliferative response of peripheral blood lympho- cytes (PBL) to fluke antigens and as the local cellular response occurring in the hepatic parenchyma (Meeusen et al., 1995). Immunohistological studies of hepatic lesions and hepatic lymph nodes have also been used to demonstrate the local immune response in goats (Martinez-Moreno et al., 1999; Perez et al., www.elsevier.com/locate/vetpar Veterinary Parasitology 131 (2005) 157–163 * Corresponding author. Tel.: +61 7 4781 4188; fax: +61 7 4779 1526. E-mail address: elizabeth.molina@jcu.edu.au (E.C. Molina). 0304-4017/$ – see front matter # 2005 Elsevier B.V. All rights reserved. doi:10.1016/j.vetpar.2005.04.028