|Rajaraman, Veena - IOWA STATE UNIVERSITY|
Submitted to: International Virtual Conference on Infectious Diseases of Animals
Publication Type: Abstract Only
Publication Acceptance Date: April 20, 1997
Publication Date: N/A
Technical Abstract: The concentration of 9,13-di-cis-retinoic acid (RA) is the most abundant isomer of RA in the circulation of calves and their dams during the immediate postpartum period. Retinoic acids, particularly all-trans-RA, can have a profound influence on the immune system. In order to evaluate the immunomodulatory potential of this unique isomer of RA, responses of resting and pokeweed mitogen-stimulated bovine blood MNL from precolostral neonatal calves to physiologic concentrations of 9,13-di-cis-RA were evaluated in vitro. The MNL were isolated at the same times from cows and their precolostral calves immediately after parturition and from non-pregnant heifers. Production of polyclonal IgM and interferon-gamma (IFN) by resting and mitogen-stimulated cultures of MNL was not affected by 9,13-di-cis-RA. At 25 nM, 9,13-di-cis-RA inhibited (P < 0.05) mitogen-induced proliferation of MNL from nongravid heifers, and had no effect on the proliferation of MNL from the dams or their calves. Overall, these suggest that 9,13-di-cis-RA at physiologic concentrations has negligible effect on the proliferation and function of MNL of precolostral calves and their dams.