Prof. Takehiko Yokomizo isolated BLT1, a gene for leukotriene B4, from human leukocytes. He established a line of mice that lack BLT1 gene, and compared their phenotypes with those of wild-type mice in various inflammatory disease models . When he induced a bronchial asthma in mice, BLT1-null mice did not show any asthmatic responses, showing that BLT1-null mice are protected from bronchial asthma. He also found that BLT1 receptor is expressed in eosinophils, and BLT1-null eosinophils did not migrate into the asthmatic lung. He is now collaborating with various pharmaceutical companies to develop BLT1 antagonists that specifically inhibit BLT1 receptor to prevent asthmatic attack and other allergic reactions in the patients.