Association between Galectin-13 Expression and Eosinophilic Airway Inflammation in Chronic Obstructive Pulmonary Disease

Figures & data

Figure 1. Levels of galectin-13 in plasma and sputum. (A) The plasma galectin-13 levels in AECOPD patients (n = 44), stable COPD (n = 16), and healthy controls (n = 15). (B) The induced sputum galectin-13 levels in AECOPD patients (n = 18), stable COPD patients (n = 9), and healthy controls (n = 8). (C) The correlation between plasma and induced sputum galectin-13 expression.

Table 1. Clinical characteristics and laboratory parameters of study subjects.

Characteristic	AECOPD patients	Stable COPD patients	Healthy controls	P1	P2	P3
Number of patients	44	16	15	/	/	/
Sex (M/F)	44 (100%)	16 (100%)	15 (100%)	/	/	/
Age (years)	64.5 (58.7–70)	65 (58–69)	65 (60.5–68)	0.99	0.88	0.91
BMI (kg/m^2)	21.7 (20.3–24.6)	22.0 (20.9–23.7)	23.7 (21.6–25.3)	0.90	0.23	0.15
Smoking history (pack-years)	32 (28.5–40)	30 (25–42.5)	30 (27.5–40)	0.93	0.52	0.81
Exacerbation frequency (times/year)	1 (0–1)	0 (0–1)	/	0.09
FEV1 (L)	1.53 (1.25–1.63)	1.57 (1.47–1.64)	2.63 (2.31–3.24)	0.35	<0.0001	<0.0001
FVC (L)	2.91(2.28–3.35)	2.82 (2.10–3.58)	3.48 (3.25–4.28)	0.65	0.003	0.01
FEV1 pred (%)	59.85 (49.39–65.15)	62.10 (56.90–64.68)	100.38 (95.97–104.52)	0.32	<0.0001	<0.0001
FEV1/FVC (%)	53.13 (46.61–55.53)	57.45 (52.36–64.80)	73.03 (71.54–74.65)	0.07	<0.0001	0.0002
Leukocytes counts (10^9L)	8.96 (7.19–10.27)	4.95 (4.62–5.79)	4.74 (3.89–5.03)	<0.0001	<0.0001	0.07
Neutrophils (10^9L)	6.52 (5.29–8.24)	3.14 (2.92–3.42)	3.31 (2.34–3.54)	<0.0001	<0.0001	0.73
Eosinophils (10^9L)	0.17 (0.07–0.36)	0.12 (0.08–0.25)	0.11 (0.06–0.14)	0.36	0.16	0.45
Serum CRP (mg/L)	5.55 (3.53–9.55)	1.90 (1.20–2.45)	2.60 (1.42–3.46)	<0.0001	0.0002	0.20
Serum PCT (ug/L)	0.05 (0.03–0.09)	0.02 (0.01–0.05)	0.02 (0.02–0.04)	0.002	0.01	0.45
Serum Galectin-13 (ng/mL)	53.17 (40.70–65.41)	38.22 (35.74–42.57)	29.56 (25.86–36.36)	0.0009	<0.0001	0.02

Data are presented as median (interquartile range). FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity. P1-AECOPD patients compared with stable COPD patients; P2-AECOPD patients compared with healthy controls; P3- stable COPD patients compared with healthy controls.

Figure 2. The correlation between galectin-13 expression and systemic inflammation factors. Correlations between the level of galectin-13 (measured in plasma) and leukocytes (A), neutrophils (B) in peripheral blood, CRP (C), PCT (D) in plasma.

Figure 3. Increased plasma galectin-13 expression is associated with airway eosinophilic inflammation in COPD. (A) The association between plasma galectin-13 levels and the percentage of eosinophils in peripheral blood. (B) Plasma galectin-13 levels in COPD subjects with different eosinophil counts in peripheral blood. (C) The association between epithelial galectin-13 levels and FeNO. (D) Plasma galectin-13 levels in COPD subjects with different levels of FeNO.

Figure 4. Correlation Between FEV₁ (A), FVC (B), FEV₁ pred (%) (C), FEV₁/FVC (%) (D) and galectin-13.

Table 2. Multiple linear regression analysis.

Parameter	R Square	β	p value	95%CI
Age	0.66	−0.16	0.623	(−0.78 to 0.47)
BMI		1.23	0.089	(−0.19 to 2.66)
Smoking history		0.02	0.936	(−0.52 to 0.56)
FEV1 pred (%)		−0.85	0.000*	(−1.20 to −0.51)
FEV1/FVC (%)		−0.22	0.442	(−0.78 to 0.35)
FeNO		0.56	0.049*	(−0.003 to 1.12)
Leukocytes count		−2.98	0.110	(−6.66 to 0.69)
Neutrophil count		3.29	0.134	(−1.05 to 7.62)
Eosinophil count		41.13	0.004*	(13.68 to 68.58)
CRP		1.17	0.111	(0.28 to 2.63)
PCT		38.66	0.234	(−25.76 to 103.07)

*p < 0.05, the result is statistically significant.

Figure 5. Alterations in plasma galectin-13 (A) and serum CRP (B).