The Role of Circulating Soluble CD74 in Acute Lung Injury

Overview

Efforts to identify circulating factors that predict severity of acute lung injury/acute respiratory distress syndrome（ALI/ARDS） patients is unrevealing. The primary purpose of this study is to verify our hypothesis that soluble CD74 might be a potential novel ALI/ARDS biomarker.

Acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) is a devastating cause of morbidity and mortality characterized by alveolar epithelial and endothelial injury. Despite recent advances in pathogenetic mechanisms and therapy strategies of ALI, efforts to identify circulating factors that predict severity of ALI/ARDS patients have been unrevealing. CD74 (also known as a major histocompatibility complex (MHC) class II invariant chain) is a type II transmembrane protein, recently found to be the high-affinity receptor of macrophage migration inhibitory factor (MIF). MIF promotes neutrophil accumulation in alveolar space via binding to CD74 expressed on the cell surface. Our previous study， consistent with others, has shown that MIF was highly expressed in acute lung injury (ALI). In addition, we also detected highly CD74 expression in lipopolysaccharide (LPS)-induced ALI mouse model. Recently, a circulating form of CD74 was discovered in autoimmune liver disease. Similarly, we investigated the existence of soluble form of CD74 in serum and bronchoalveolar lavage fluid (BALF) in ALI mouse model and burn or trauma related ALI patients. Based on these finds, we postulated that soluble CD74 might participate in regulating lung inflammation and be a potential novel ALI/ARDS biomarker.

Conditions

Eligibility

Locations (1)

Outcomes