title: Lymphocyte blastogenic responses of calves experimentally infected with Ostertagia ostertagi.
abstract: Twelve 9-week-old calves were divided into four groups; two groups were maintained helminth-free as controls and the other groups were given Ostertagia ostertagi infective-stage larvae (L3) orally. One group received 100,000 L3 as a single inoculum and the other group received L3 in increasing dosages at weekly intervals for 8 consecutive weeks. The blastogenic responses to concanavalin A (Con A), phytohemagglutinin (PHA), and a soluble larval antigen from O. ostertagi (SLA) of peripheral blood lymphocytes were evaluated using tritiated thymidine incorporation into DNA as a measure of blastogenesis. The responses to Con A of all infected calves were significantly depressed while the responses to PHA were not. SLA, at concentrations of 4 micrograms ml-1 and above, caused blastogenic activity in lymphocytes from uninfected calves. Using SLA at 1 microgram ml-1 in lymphocyte cultures supplemented with autologous serum, an antigen-induced blastogenic response was detected in calves receiving serial inoculations of L3.
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000276:immunology; D002417:Cattle; D002418:Cattle Diseases / Q000097:blood / Q000276:immunology*; D003208:Concanavalin A / Q000494:pharmacology; D007958:Leukocyte Count; D008213:Lymphocyte Activation; D010028:Ostertagia / Q000276:immunology; D010029:Ostertagiasis / Q000097:blood / Q000276:immunology / Q000662:veterinary*; D010835:Phytohemagglutinins / Q000494:pharmacology; D014252:Trichostrongyloidiasis / Q000662:veterinary*
chemical_list: D000947:Antigens, Helminth; D010835:Phytohemagglutinins; D003208:Concanavalin A