Table 2.

Semi-quantitative analysis of pulmonary Lipocalin-2 expression.

	Bronchial epithelium	Alveolar walls	Lung parenchyma	BO lesions
	Y/N (%)	Y/N (%)	Y/N (%)	Y/N (%)
BOS (n = 11)	11/0 (100)	0/11 (0)		0/11 (0)
RAS (n = 6)	6/0 (100)	4/2 (66,6)	0/6 (0)
IPF (n = 10)	10/0 (100)	2/8 (20)	0/10(0)
CF (n = 10)	9/1 (90)	0/10 (0)	0/10 (0)
Control (n = 9)	5/4 (55,5)	0/9 (0)	0/9 (0)

Immunohistochemistry for Lipocalin-2 was performed on lung specimens of patients with CLAD (RAS and BOS), end stage pulmonary fibrosis (IPF and CF) and healthy controls. Antibody reactivity in BO lesions of BOS patients, bronchial epithelium, alveolar walls and lung parenchyma was assessed.

Y positive antibody staining, N negative antibody staining, BO bronchiolitis obliterans, BOS bronchiolitis obliterans syndrome, RAS restrictive allograft syndrome, IPF idiopathic pulmonary fibrosis CF cystic fibrosis.