YKL-40 is expressed by macrophages in bronchial-biopsy specimens and cytospin of broncho-alveolar lavage from patients with asthma [149] and chronic obstructive pulmonary disease (COPD) [150], and in sarcoid lesions of patients with pulmonary sarcoidosis [151]. This evidence concerns the gene CHI3L1 and pulmonary sarcoidosis.