Peripheral blood monocytes significantly potentiated the mitogenic response of bovine fetal thymocytes to Concanavalin A as measured by incorporation of [3H] thymidine into cellular DNA. Mononuclear cells obtained from either normal or Mycobacterium bovis sensitized cattle were cultured with or without purified protein derivative (PPD) for 24 hours at which time bovine fetal thymocytes and concanavalin A were added. After 3 days of culture, both activated or non-activated monocytes significantly potentiated Con A-induced blastogenic responses. Depletion of monocytes from thymocyte cultures completely abrogated thymocyte responses to Concanavalin A.
Bibliographical noteFunding Information:
Supported in part by the Minnesota Agricultural Experiment Station, the Cooperative Research Service and Veterinary Services, U.S. Department of Agriculture, Hyattsville, MD, and the Ministry of Education and Social Welfare, Government of India, New Delhi, India.