Distribution and identification of Mycobacterium tuberculosis lineage in Kashgar prefecture

Objectives

Kashgar prefecture is an important transportation and trade hub with a high incidence of tuberculosis. The following study analyzed the composition and differences in Mycobacterium tuberculosis (M.tb) lineage and specific tags to distinguish the lineage of the M.tb in Kashgar prefecture, thus providing a basis for the classification and diagnosis of tuberculosis in this area.

Methods

Whole-genome sequencing (WGS) of 161 M.tb clinical strains was performed. The phylogenetic tree was constructed using Maximum Likelihood (ML) based on single nucleotide polymorphisms (SNPs) and verified through principal component analysis (PCA). The composition structure of M.tb in different regions was analyzed by combining geographic information.

Results

M.tb clinical strains were composed of lineage 2 (73/161, 45.34%), lineage 3 (52/161, 32.30%) and lineage 4 (36/161, 22.36%). Moreover, the 3 lineages were subdivided into 11 sublineages, among which lineage 2 included lineage 2.2.2/Asia Ancestral 1 (9/73, 12.33%), lineage 2.2.1-Asia Ancestral 2 (9/73, 12.33%), lineage 2.2.1-Asia Ancestral 3 (18/73, 24.66%), and lineage 2.2.1-Modern Beijing (39/73, 53.42%). Lineage 3 included lineage 3.2 (14/52, 26.92%) and lineage 3.3 (38/52, 73.08%), while lineage 4 included lineage 4.1 (3/36, 8.33%), lineage 4.2 (2/36, 5.66%), lineage 4.4.2 (1/36, 2.78%), lineage 4.5 (28/36, 77.78%) and lineage 4.8 (2/36, 5.66%), all of which were consistent with the PCA results. One hundred thirty-six markers were proposed for discriminating known circulating strains. Reconstruction of a phylogenetic tree using the 136 SNPs resulted in a tree with the same number of delineated clades. Based on geographical location analysis, the composition of Lineage 2 in Kashgar prefecture (45.34%) was lower compared to other regions in China (54.35%-90.27%), while the composition of Lineage 3 (32.30%) was much higher than in other regions of China (0.92%-2.01%), but lower compared to the bordering Pakistan (70.40%).

Conclusion

Three lineages were identified in M.tb clinical strains from Kashgar prefecture, with 136 branch-specific SNP. Kashgar borders with countries that have a high incidence of tuberculosis, such as Pakistan and India, which results in a large difference between the M.tb lineage and sublineage distribution in this region and other provinces of China.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07307-4.

Anti-breast cancer activity of resveratrol encapsulated in liposomes

Resveratrol (RES) is a naturally occurring and effective drug for tumor prevention and treatment. However, its low levels of aqueous solubility, stability, and poor bioavailability limit its application, especially when used as a free drug. In this study, RES was loaded into peptide and sucrose liposomes (PSL) to enhance the physico-chemical properties of RES and exploit RES delivery mediated by liposomes to effectively treat breast cancer. RES loaded PSL (the complex: PSL@RES) were stable, had a good RES encapsulation efficiency, and prolonged RES-release in vitro. PSL@RES was exceptionally efficient for inhibiting the growth of cancer cells, as the IC₅₀ of PSL@RES in MCF-7 cells was found to be only 20.89 μmol L^-1. The therapeutic efficacy of PSL@RES was evaluated in mice bearing breast cancer. The results showed that PSL@RES at a dosage of 5 mg kg^-1 was more effective than 10 mg kg^-1 free RES, and PSL@RES inhibited tumor growth completely at a dosage of 10 mg kg^-1. PSL@RES induced apoptosis in breast tumor by upregulation of p53 expression. This then downregulated Bcl-2 and upregulated Bax, thereby inducing Caspase-3 activation. More importantly, encapsulation of RES within peptide liposomes greatly reduced the toxicity of free RES to mice. Overall, the simple formulation of liposomal nanocarriers of RES developed in this study produces satisfactory outcomes to encourage further applications of liposomal carriers for the treatment of breast cancer.