To explore the effects of complete Freund’s adjuvant on autophagy protein expression in rat tuberculous wound model. The experimental research method was used. In the first batch, 12 6-week-old male Sprague-Dawley (SD) rats were sensitized by subcutaneous injection of complete Freund’s adjuvant into the hips. Three weeks later, the rats were infected with attenuated Mycobacterium bovis (BCG) subcutaneously on both sides of the back spine. After establishing the tuberculosis wound rat model, according to the random number table (the same grouping method below), the rats were divided into 8 d infection group, 15 d infection group, 32 d infection group, and 43 d infection group, with 3 rats in each group, with continue noramal feeding to the corresponding number of days after infection. In the second batch, 23 6-week-old male SD rats were divided into blank control group (=3,normal feeding without any treatment), BCG alone group (=5), BCG+rapamycin group (=6), BCG+3-methyl group (=6), and BCG+starvation group (=3). The last 4 groups of rats were sensitized as before, and infected as before 1 week later. Rats in the BCG alone group were fed normally without any treatment. Rats in BCG+rapamycin group or BCG+3-Methyladenine group were infected with intraperitoneal injection of rapamycin or 3-Methyladenine once every other day and fed normally. Rats in BCG+starvation group were hungry for 48 hours after infection to cause a sudden weight loss and then fed normally. All the rats in the first batch of 4 groups were sacrificed on the corresponding days after infection, and the tissue where the buttocks were injected with complete Freund’s adjuvant were harvested; the tissue of rats in second batch of BCG alone group, BCG+rapamycin group, BCG+3-Methyladenine were harvested the same as before 7 days after infection, and all rats in the blank control group were taken from the same tissue at the same time point. Hematoxylin-eosin staining was performed to observe the structure and morphology of tissue cells at the site where complete Freund’s adjuvant was injected; immunohistochemistry was used to observe the protein expressions of Beclin1, microtubule-associated protein 1 light chain 3B (LC3B) in the tissue where complete Freund’s adjuvant was injected. Data were statistically analyzed with Kruskal-Wallis test and Bonferroni correction. Inflammatory cell infiltration was observed in the tissue of rats in 8 d infection group where the complete Freund’s adjuvant was injected, granuloma formation was seen in 15 d infection group, part of tissue cell necrosis was seen in 32 d infection group and 43 d infection group, and cell necrosis in 43 d infection group was worse than that in 32 d infection group. Seven days after infection, inflammatory cell infiltration was seen in the tissue where the complete Freund’s adjuvant was injected of rats in BCG alone group, BCG+rapamycin group, BCG+3-Methyladenine group, and BCG+starvation group, while no inflammatory cell infiltration were observed in blank control group. There were no statistically significant differences in the protein expressions of Beclin1 and LC3B in the tissue where the complete Freund’s adjuvant was injected of rats in 8 d infection group, 15 d infection group, 32 d infection group, and 43 d infection group (=1.923, 5.821, >0.05). Seven days after infection, the relative expression of Beclin 1 and LC3B protein in the tissue where the complete Freund’s adjuvant was injected of rats in blank control group, BCG alone group, BCG+rapamycin group, BCG+3-Methyladenine group, and BCG+starvation group were respectively 0.325 (0.250, 0.360), 3.225 ( 1.340, 3.987), 4.823 (2.630, 6.559), 4.216 (1.790, 5.969), 1.765 (0.865, 2.649), and 0.301 (0.264, 0.516), 2.865 (1.455, 5.768), 1.033 (0.398, 1.873), 1.168 (0.429, 1.907), 0.655 (0.283) , 1.652). The protein expression of Beclin1 in the tissue where the complete Freund’s adjuvant was injected of rats in BCG+rapamycin group was significantly higher than that of blank control group (<0.05). The protein expression of LC3B in the tissue where the complete Freund's adjuvant was injected of rats in BCG alone group was significantly higher than that of blank control group <0.05). Complete Freund's adjuvant can enhance the expression levels of local tissue autophagy-related proteins Beclin1 and LC3B in rat tuberculous wound model.

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