A Preliminary Protocol for Induction of Tuberculosis Spondylitis by Mycobacterium Tuberculosis Strain H۳۷R: In-vivo New Zealand White Rrabbits Model

Background: Proper animal model is a critical prerequisite of any experimental study, while it is a lack for tuberculosis spondylitis. This study aimed to validate a protocol for induction of tuberculosis spondylitis in an animal model.Methods: Ten New Zealand white rabbits were used and divided randomly into four experimental groups (n = ۸), with ۲ rabbits in each group, and the control group (n = ۲). A ۰.۲ mL suspension of ۱۰۸ CFU/mL H۳۷Rv strain M. tuberculosis was delivered into the drilled hole with a depth of ۶-۱۰ mm at the midpoint of the ۱۲th thoracal corpus compared with the saline in the control group. Evaluation of imaging examination by using plain X-ray was done within the targeted time followed by euthanasia protocol.Results: A survival rate of ۱۰۰% was observed in the present study with all rabbits having stable vital signs during the incubation period. Group ۳ with an incubation period of ۶ weeks showed the highest success rate for inoculation of M. tuberculosis bacteria in which ۷ samples were positive. This was followed by group ۲ (۷۵%, incubation ۴ weeks), group ۱ (۳۷.۵%, incubation ۲ weeks), and group ۴ (۱۲.۵%, incubation ۸ weeks). The high positive rates were also reported by using culture and PCR staining, ۶۲.۵% and ۷۵%, respectively. A slight destruction of the vertebral body was observed in both groups ۲ and ۳ starting at ۴ weeks, postoperatively. Histopathology specimen exhibited an infiltration of numerous inflammatory cells. Conclusions: Establishment of spondylitis tuberculosis model by using New Zealand white rabbit could be successfully formed through ۰.۲ mL suspension of ۱۰۸ CFU/mL M. tuberculosis strain H۳۷Rv with a direct inoculation method towards the midpoint of the ۱۲th thoracal vertebral body. In addition, this model showed a high positive rate with a ۱۰۰% survival rate in both control and ۴ treatment groups.

کلیدواژه ها:

Spondylitis Tuberculosis ، Spinal Tuberculosis ، animal model ، New Zealand rabbit ، Mycobacterium Tuberculosis