title: Effect of conditioned media from chicken and turkey intestinal cell cultures on invasion by sporozoites of three species of avian coccidia.
abstract: The effect of conditioned media from cultures of turkey and chicken intestinal cells on cellular invasion by sporozoites of avian Eimeria species was examined in vitro. Media conditioned by the growth of cells from the ceca, mid-intestine (area of the yolk stalk diverticulum), and duodenal loop were examined for their ability to enhance invasion. Conditioned medium from cultures of turkey cecal cells significantly enhanced invasion by the turkey coccidia Eimeria adenoeides, by 2.4-fold, and E. meleagrimitis, by 2.2-fold, as compared with invasion in the presence of control medium. Conditioned medium from mid-intestinal cell cultures enhanced invasion by the two coccidial species by 2.0- and 2.1-fold, respectively. The enhancement occurred with conditioned media from early (1) as well as later (11) passages of cells. This suggests that the enhancing factor was produced by fibroblast-like cells, the predominant cell type at both early and late passages, and not by epithelial-like cells that had disappeared by the first or second passage. Additionally, conditioned media from cultures of chicken cecal and duodenal loop cells significantly enhanced invasion by the turkey cecal coccidium, E. adenoeides, (1.7- and 1.6-fold, respectively). This was less enhancement than was caused by the turkey cell conditioned media. Heat treatment (56 degrees C for 45 min) of conditioned media failed to alter the effect on invasion. Neither the turkey or chicken cecal cell media nor conditioned media from any other chicken intestinal cell cultures enhanced invasion by E. tenella, the chicken cecal coccidium. Although morphologically dissimilar when they were first plated, the gross appearance and growth of the turkey and chicken cells when conditioned media was collected was comparable.
authors.affiliation: United States Department of Agriculture, Livestock and Poultry Sciences Institute, Beltsville, Maryland 20705, USA. paugusti@ggpl.arsusda.gov
authors.forename: P C
authors.initials: PC
authors.lastname: Augustine
authors.forename: M C
authors.initials: MC
authors.lastname: Jenkins
mesh_terms: D000818:Animals; D002460:Cell Line; D002478:Cells, Cultured; D002645:Chickens; D006224:Cricetinae; D017077:Culture Media, Conditioned; D004539:Eimeria / Q000254:growth & development / Q000472:pathogenicity*; D016786:Eimeria tenella / Q000254:growth & development / Q000472:pathogenicity*; D007422:Intestines / Q000166:cytology*; D007668:Kidney / Q000166:cytology; D014422:Turkeys
chemical_list: D017077:Culture Media, Conditioned