Medical application of protein engineering is our goal, based on understanding of chemical property of proteins with protein manipulation technology. Graduate students master precious technique on various recombinant protein expression and purification, as well as solubilization techniques for unstable proteins. They challenge to apply these techniques for medical applications. Recent our focus is immuneoncology. We are developing antibody detection technology which allows quantitative and highly-sensitive evaluation of antitumor immune response by preparation of comprehensive tumor antigens. The key to improve cancer immunotherapy requires technology for personalized medicine. We open the new way for cancer precision medicine assisted by protein engineering.