Red plaque formation of Coxiella burnetii and reduction assay by monoclonal antibodies
Cheng, X.X.; Yu, S.R.; Yu, G.Q.
Acta Virologica 33(3): 281-289
1989
ISSN/ISBN: 0001-723X PMID: 2570515 Document Number: 343572
A red plaque technique for C. burnetii which utilizes primary chicken embryo cells, is described. Red plaques could be consistently detected as early as 6 days, usually 8 days post inoculation (p.i.), reflecting that C. burnetii proliferated within the phagolysosomes of host cells. Incubation with phase II monoclonal antibodies or inactivated immune sera containing phase I and phase II antibodies or phase II antibodies only, markedly reduced phase II C. burnetii red plaques. On the other hand, red plaques from phase I organisms increased several times when phase I cells were mixed with phase I monoclonal antibodies or inactivated immune sera containing phase I and phase II antibodies. By indirect red plaque reduction assay red plaque production by phase II cells could be reduced as well.