Fig. 5

Principal component analysis (PCA) for SH and SD groups together. a Scree plot from PCA showing as many components as variables (x-axis), the parallel analysis for the eigenvalue (y-axis) for component 3 was 1.134 and a dashed line is at that level including only the first two components in the final PCA. b The components plot in rotated space including component 1 as an orange area (immunoregulatory effect of spleen denervation) and component 2 as a blue area (immunoregulatory effect of NaHCO₃ treatment). The first component is loaded with Treg, CD4-FoxP3 + T cells, M2-like macrophages, and surgery (zero representing sham surgery and one spleen denervation). The second component is loaded with M1-like macrophages, the granularity index, and the treatment (zero representing H₂O and one NaHCO₃ treatment). The area where blue and orange overlap represents the only complex variable in the PCA, which is M2-like macrophages. These cells had a predominant loading factor of 0.518 on Component 1, however, the loading for Component 2 was close to 0.427. Figure created with SPSS 28, and Prism GraphPad