Fig. 5

Growth kinetics of the B. melitensis TZ strain in pure culture and infected cell lines. A Growth characteristics of B. melitensis TZ, B. melitensis 16 M and B. melitensis M5-90 in TSB. The optical density was obtained every 4 h before 24 h and at 36 h, 48 h, and 72 h with three repetitions. B Intracellular replication of B. melitensis TZ, B. melitensis 16 M and B. melitensis M5-90 in infected RAW 264.7 cells. C. Intracellular replication of B. melitensis TZ, B. melitensis 16 M and B. melitensis M5-90 in infected THP-1 cells. D. Intracellular replication of B. melitensis TZ, B. melitensis 16 M and B. melitensis M5-90 in infected HeLa cells. The level of initial infection was the same for all B. melitensis strains as described in the Materials and Methods. At 0, 2, 8, 24, and 48 h postinfection, infected macrophages were lysed, and supernatants were diluted for CFU enumeration