The human immune system is one of the most fascinating components of the human body. As an example, once a person has contracted measles, such individual may never develop symptoms of measles again. Despite striking advances in modern medicine in recent years together with rapid changes in the standard of living and quality of life, we are still being challenged by refractory immune disorders, viral infections and cancers. Fascinated by the human immune system, we became engaged in research since the foundation of Japan Immunoresearch Laboratories Company Limited (JIMRO) in the hope of obtaining further insights into immune disorders and use such knowledge to challenged the disorders. As part of our response to the existing challenges, we have devoted major emphasis on lymphocytes, monocytes and granulocytes which are major players in immune functions. As a fruit of our endeavours, we developed a therapeutic device, the only one in the world, which selectively adsorbs granulocytes and monocytes / macrophages from the blood. Our device received blessings from the Japanese Ministry of Health and Welfare for production and marketing in October 1999. We are very pleased and honoured to provide this product for therapeutic services in Japan as the first market in the world. With this therapeutic device, we hope that we can contribute to alleviating the suffering of people with refractory or incurable diseases. We have arrived at the doorstep of the twenty first century with a renewed determination to continue our devoted efforts to develop creative and innovative products so that we can provide more effective challenges to refractory diseases.