Multiple Circulating Cytokines Are Coelevated in Chronic Obstructive Pulmonary Disease

Figure 2

Median concentrations of 14 cytokines in serum samples from the following groups of subjects: NS (), ExS (), CS (), COPD ex-smokers (COPD-Ex, ), and COPD current smokers (COPD-C, ). The symbol representing each cytokine is shown in the figure. The solid, short horizontal lines represent the median concentrations of the 14 cytokines in each group. The dashed horizontal line represents the median value of the NS group. COPD-Ex and COPD-C were significantly different from NS (), ExS (§), and CS (†). There were no significant differences between NS, ExS, and CS or between COPD-Ex and COPD-C. refers to significant differences between the NS group and the COPD-Ex or COPD-C groups. § refers to significant differences between the ExS group and the COPD-Ex or COPD-C groups. † refers to significant differences between the CS group and the COPD-Ex or COPD-C groups. The number of symbols refer to the level of statistical significance, so one symbol (, §, †) indicates ; two symbols (, §§, ††) indicate ; three symbols (, §§§, †††) indicate ; four symbols (, §§§§, ††††) indicate ; these values were determined by Friedman test followed by Dunn’s multiple comparisons test. The same applies to Figures 3 and 4.