High Expression of Cathepsin E is Associated with the Severity of Airflow Limitation in Patients with COPD

Figures & data

Table 1.  Demographic and lung function data for the study subjects

	Non-smoking control	Smoking control	COPD stage I	COPD stage II	COPD stage III	COPD stage IV
Subjects	15	20	20	15	15	15
Male/female	11/4	15/5	14/6	12/3	14/1	12/3
Age (years)	62.27 ± 6.52	62.25 ± 6.22	63.90 ± 4.75	63.67 ± 5.53	63.67 ± 5.97	62.80 ± 4.54
Smoking (pack-years)	0	31.10 ± 3.37**	30.50 ± 6.55**	30.33 ± 4.91**	29.20 ± 3.84**	29.87 ± 3.38**
FEV1%	92.33 ± 5.91	89.80 ± 5.34	88.45 ± 4.49*	61.93 ± 6.79**	40.20 ± 4.80**	24.87 ± 2.07**
FEV1/FVC %	85.00 ± 3.02	83.30 ± 3.40	64.30 ± 4.23**	58.13 ± 4.41**	47.73 ± 4.91**	34.67 ± 2.80**
MMEF(L/s)	103.13 ± 11.70	95.10 ± 10.81	60.55 ± 7.25**	26.93 ± 6.87**	18.53 ± 2.80**	7.07 ± 1.94**
PEF (%predicted)	93.07 ± 5.90	89.70 ± 5.47	81.00 ± 6.88**	55.33 ± 7.00**	50.27 ± 9.74**	31.60 ± 4,90**
Emphysema score	0.87 ± 0.99	1.45 ± 0.89	1.85 ± 0.75*	2.27 ± 0.88**	2.53 ± 0.915**	3.27 ± 0.80**
CatE (ng/mL)	462.20 ± 97.30	424.60 ± 125.40	591.95 ± 125.71**	712.00 ± 107.38**	1126.40 ± 138.38**	1474.33 ± 220.97**
EIC (U/L)	623.73 ± 37.08	517.25 ± 53.37**	413.95 ± 62.60**	370.20 ± 72.35**	214.53 ± 17.30**	142.93 ± 8.44**

Continuous data are expressed as mean ± SD.

*P < 0.05,

**P < 0.01 compared with the non-smoking control group.

MMEF, maximal mid-expiratory flow; PEF, peak expiratory flow.

Table 2.  Cellular analysis of sputum samples

Subjects	N	Total cell counts (×10^9/L)	AM (×10^9/L)	AM%	Neu (×10^9/L)	Neu%
Non-smoking control	15	2.95 ± 0.39	1.82 ± 0.19	62.13 ± 2.54	1.12 ± 0.21	37.87 ± 2.54
Smoking control	20	7.06 ± 1.22*	3.44 ± 0.67*	48.56 ± 2.72*	3.62 ± 0.60*	51.45 ± 2.72*
COPD stage I	20	10.20 ± 0.86*	4.49 ± 0.41*	44.03 ± 1.04*	5.70 ± 0.47*	55.97 ± 1.04*
COPD stage II	15	11.13 ± 0.75*	4.65 ± 0.31*	41.77 ± 1.67*	6.49 ± 0.53*	58.23 ± 1.67*
COPD stage III	15	12.27 ± 0.98*	4.76 ± 0.44*	38.83 ± 1.15*	7.50 ± 0.59*	61.17 ± 1.15*
COPD stage IV	15	13.25 ± 0.68*	4.66 ± 0.28*	35.17 ± 0.97*	8.59 ± 0.46*	64.83 ± 0.97*

Continuous data are expressed as mean ± SD.

*P < 0.01 compared with the non-smoking control group.

AM, alveolar macrophages; Neu, neutrophils.

Figure 1.  Cat E in serum was inversely correlated with FEV₁% in patients with COPD (r = −0.915, P < 0.01).

Figure 2.  EIC in serum was positively correlated with FEV₁% in patients with COPD (r = 0.926, P< 0.01).

Figure 3.  EIC was inversely correlated with Cat E in the serum of patients with COPD (r = −0.922, P< 0.01).