|Ametaj, Burim - IA STATE UNIV., AMES, IA|
|Beitz, Donald - IA STATE UNIV., AMES, IA|
Submitted to: American Dairy Science Association Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: March 8, 1996
Publication Date: N/A
Technical Abstract: Interferon-gamma is key to the development of normal cell-mediated immune responses because it induces an antiviral state, promotes expression of major histocompatibility antigens, and enhances activation of macrophages and natural killer cells. Retinoic acids, metabolites of vitamin A, have been shown to modulate IFN-gamma secretion by PBML from non-ruminant animal species. Effects of retinoic acid (RA) isomers on pokeweed mitogen (PWM)-induced IFN- gamma secretion by bovine PBML were examined. Six healthy, non- gravid, age-matched Holstein cattle served as donors of PBML. Individual and combined effects of RA isomers (at 10**-12 to 10**-7 M) on IFN-gamma secretion were examined in 24-, 48-, and 72-h PBML cultures. Interferon-gamma culture supernatants was measured using an IFN-gamma-capture ELISA. Individually, all-trans- and 13- cis-RA had no effect (P >.05) on IFN-gamma secretion by PWM- stimulated PBML. However, when added in combination, these isomers inhibited IFN-gamma secretion (P <.05). Individually, 9-cis-RA and, to a lesser extent, 9,13-di-cis-RA significantly (P <.05) inhibited IFN- gamma secretion. Together, these isomers produced greater inhibition (P <.05) of IFN-gamma secretion than when added individually to the cultures.