 The receptor for advanced glycation end products RAGE was recently identified as a promising new marker of alveolar type I cell injury. RAGE is a member of the immunoglobulin superfamily that acts as a multiligand receptor and is involved in propagating inflammatory responses. While the precise function of RAGE remains unclear, the elevated levels of RAGE, and its soluble isoform sRAGE, correlate with severity of ALIARDS in human and animal studies, and RAGE levels could reflect impaired alveolar fluid clearance. Thus, it is possible that elevated levels of RAGE in ALIARDS derive in part from RAGEs role in systemic inflammatory cascades rather than purely from its release from alveolar type I cells. 