First approach for the propagation of Anaplasma marginale (MEX-31-096) in Rm-sus tick cells

Abstract

Anaplasma marginale is an intraerythrocytic bacterium transmitted by ticks that causes bovine anaplasmosis. One of the limitations in the study of this microorganism has been the difficulty to cultivate it in vitro. To date, the cultivation of Mexican strains of A. marginale has not been reported. In this work we show the first approach to establish the infection and the propagation of the strain MEX-31-096 in cells of ticks Rm-sus, using as inoculum  freshly erythrocytes. The infection was confirmed by light microscopy, observing the development of A. marginale in the Rm-sus cells from the 2nd day after inoculation (dpi) and obtaining 80% of infected cells at day 8 dpi. In addition, the amplification of the variable region of the msp1a gene by PCR endpoint was positive. After the 5th subculture it was not possible to detect the bacteria. These results are valuable for the development of our research since they demonstrate that A. marginale (MEX-31-096) has the ability to infect and spread in Rm-sus cells, which will allow obtaining these microorganisms under controlled conditions, and in less time.