Figure 2.

Scatter plots of plasma monocyte chemoattractant protein 1 (MCP-1) levels in 45 healthy control, 12 non-VAP subjects, and 30 patients with VAP who were divided into acute and remission stage according to ELISA results. MCP-1 concentration was significantly higher in the acute stage in VAP patients when compared with non-VAP subjects (p = 0.0006) and healthy controls (p < 0.0001), and remarkably decreased after treatment (p = 0.0082). Moreover, there was also significant difference between non-VAP subjects and healthy controls (p = 0.0007). Plasma MCP-1 levels were significantly increased in the remission stage in VAP patients when compared with non-VAP subjects (p = 0.0149) and healthy controls (p < 0.0001). Each dot represents a single patient. The solid lines mark the mean values. VAP_AC, VAP in acute stage, VAP_RE, VAP in remission stage. The Kruskal–Wallis test for multiple comparisons was used to determine the differences among the means of various plasma MCP-1, then the Mann–Whitney U test was employed to compare the results between groups, and the paired sample t-test was used for comparisons between acute and remission stage of VAP. * p < 0.05, ** p < 0.01, *** p < 0.001 by statistical analysis.