Figure 2.

Principal Component Analysis (PCA): PCA1 axis and PCA2 axis explained 29.1% and 27.4% of the overall variation in the data (A). In the PC scores plot, the data from TB-COPD patients exhibited significance. (B) Using the fviz_pca_ind function for visualization, it illustrates the distribution of each sample(C). The arrow colors represent the contributions of each variable to PCA. The angles between arrows indicate the relationships between variables: acute angles represent positive correlations, obtuse angles represent negative correlations, and right angles represent no correlation.