Study on the mouse model infected by Mycobacterium tuberculosis H37Ra

Objective: To Study on the pathological lesion in Balb/c mice infected with H37Ra. Methods: The mice were divided into control group and model group infected with Mycobacterium tuberculosis. Balb/c mice was injected via the tail vein with attenuated Mycobacterium tuberculosis H37Ra (1×10⁶ CFU/mouse). After infection, living bacteria, organ weight index of lung or spleen, and histopathological lesion were detected after 7, 14, and 21 days of infection. Results: Compared with the group of control, the organ coefficient of spleen increased statistically after 14 days or 21 days of infection(P<0.01 and P<0.05);The number of living bacteria in spleen tissue of infected mice increased with the days of infection and was higher in spleen tissue than that in lung tissue. Tuberculosis-like lesions were observed in spleen and lung tissue of infected mice model. Conclusions: Attenuated Mycobacterium tuberculosis H37Ra could induced tuberculosis-like lesions in Balb/c mouse via the tail vein injection.