Effect of muramyl dipeptide on apoptosis of bovine mammary gland lymphocytes in vitro

Abstract

The aim of this study was to determine whether apoptosis of lymphocytes is modulated by muramyl dipeptide (MDP) which is the minimal structural unit of peptidoglycans in Gram-positive bacteria. To this aim, apoptosis of lymphocytes was studied in in vitro environment (RPMI medium, 37 °C, 5% CO2 ) with 10 μg.ml-1 MDP. Heifers were used as mammary gland cell donors for in vitro studies. Lymphocytes from the intact mammary glands were harvested following influx induction by the phosphate buffered saline intramammary injection. Apoptosis and necrosis of lymphocytes were analysed by flow cytometry following simultaneous staining with Annexin-V and propidium iodide. The results of this study demonstrate that apoptosis of lymphocytes was delayed during in vitro incubation with MDP.