Effects of halofuginone lactate on lymphocytes and MDBK cells infected with Theileria annulata and/or vesicular stomatitis virus (VSV): an in vitro study.

Cultures of cattle lymphocytes (lymphoblasts) infected up to 90% with Theileria annulata schizonts and cultures of Madin Darby bovine kidney cells of cattle (MDBK) noninfected or infected with vesicular stomatitis virus (VSV) were exposed to different concentrations (50, 100, or 500 micrograms/ml) of halofuginone lactate in RPMI and MEM medium, respectively. It was found that a concentration of 50 micrograms/ml halofuginone was sufficient to destroy Theileria-infected as well as double-infected lymphocytes (VSV, T. annulata) within 2-6 h of incubation. The same concentration of halofuginone could also damage VSV-infected MDBK cells, leading to a rupture of the host cells, with a maximum of damaged cells within 21-29 h of incubation. In contrast, noninfected control cells (lymphocytes and MDBK cells) tolerated halofuginone at a concentration of 500 micrograms/ml even after prolonged (53-h) incubation periods.