Predictive values of plasma KL-6 in bronchopulmonary dysplasia in preterm infants

Abstract

IntroductionBronchopulmonary dysplasia (BPD) is a syndrome of respiratory distress caused by chronic lung parenchymal injury, occurring especially in preterm infants (1). BPD remains a serious problem in very low birthweight (VLBW) infants despite the use of antenatal steroids and postnatal surfactant therapy to decrease the incidence and severity of respiratory distress syndrome (RDS) (2,3). BPD has a complex and multifactorial etiology, including oxygen toxicity, preterm delivery, hypoxia/hyperoxia, infection, and inflammation (4).Many studies have suggested that lung inflammation is a major contributor to the pathogenesis of BPD (5,6). Various parameters of lung inflammation may be used to show lung inflammation. However, most of them such as N-terminal propeptide of type 3 collagen, SP-A, anti-SP-A immune complexes, nitrotyrosine, soluble E-selectin, intercellular adhesion molecule-1, allantoin, and aldehydes are not specific for lung disease or are complicated to measure (6). Krebs yon den Lundgen-6 (KL-6) is a mucinlike high-molecular weight glycoprotein that is classified into cluster 9 (MUC1) of lung tumor and differentiation antigens. It is preferentially expressed by alveolar type 2 cells and stimulates lung fibrosis through its action as a fibroblast chemotactic factor (7).There are many studies suggesting plasma KL-6 is increased in adult patients with various types of interstitial pneumonia, characterized by type 2 alveolar hyperplasia and fibrosis (8-11). KL-6 has also shown to be as a useful marker for increased alveolar vascular permeability associated with lung injury. However, plasma KL-6 levels are not elevated in noninterstitial lung diseases such as bacterial pneumonia, bronchial asthma, and pulmonary emphysema (9). Similar pathological changes seen in interstitial pneumonia in the lung are also predominant in BPD (7,12,13). Plasma KL-6 can be a clinically useful early marker for BPD. However, there are few data on the predictive characteristics of KL-6. Therefore, in the present study, we aimed to evaluate the predictive values of KL-6 in BPD within the first days of life. Materials and methods Study populationAll eligible preterm infants between May 2014 and April 2015 were prospectively enrolled in this study, specifically neonates with birthweight ≤1500 g and gestational age ≤32 Background/aim: It has been suggested that plasma KL-6 increases in premature infants with bronchopulmonary dysplasia (BPD). We aimed to evaluate the predictive values of KL-6 in BPD. Materials and methods:The study was performed in preterm neonates with birthweight ≤1500 g and gestational age ≤32 weeks. Plasma KL-6 levels were measured on postnatal days 1, 7, and 14.Results: BPD was identified in eight of the 28 study infants. On postnatal days 1 and 7, plasma KL-6 levels were similar in infants with BPD [on

The Potential of Lung Epithelium Specific Proteins as Biomarkers for COVID-19-Associated Lung Injury

“…Since KL-6 has anti-apoptotic activities on stimulated fibroblasts, an elevated serum level of KL-6 is known to be a sign of active pulmonary fibrosis. KL-6 levels are raised in the serum of patients with interstitial lung diseases (ILDs), ARDS, pulmonary tuberculosis, and bronchopulmonary dysplasia (BPD) [ 18 , 19 , 20 , 21 , 22 , 23 ]. In COVID-19, it is suspected that viruses can induce cytopathic effects against type I or II pneumocytes and contribute to lung injury [ 24 ].…”

Diagnostic value of KL-6 in idiopathic interstitial pneumonia

“…In China, studies of KL-6 have mainly focused on significant increases in the serum levels of this antigen in the context of different types of ILDs, including IPF, CVD-IP, and HP, and the results have suggested the potential diagnostic use of this parameter. In other countries, researchers have reported distinctly elevated serum KL-6 levels in patients diagnosed with IIP, radiation pneumonitis, pulmonary alveolar proteinosis, CTD-related interstitial pneumonia, non-small cell lung cancer, bronchopulmonary dysplasia in preterm infants, and neonatal high-permeability pulmonary oedema (14)(15)(16)(17). Our observation of significantly higher serum KL-6 levels in patients with IIP relative to those in patients with other lung diseases agreed with the findings of Kohno and Vij (11,18).…”

Early prediction of bronchopulmonary dysplasia: can noninvasive monitoring methods be essential?

“…Krebs yon den Lundgen-6 (KL-6) is a high-molecular-weight gp that is predominantly produced by Type II alveolar cells and induces lung fibrosis by acting as a fibroblast chemotactic factor [ 40 ]. A case–control study including 74 preterm infants of GA <32 weeks revealed that the cord plasma KL-6 concentrations in the BPD group were substantially higher than those in the non-BPD group (p<0.05).…”