Research & Development
Oral bacteria and intestinal bacteria : Expanse from study of sugar chain and lectin
MBL has been recognized for research reagent and diagnostic reagent business mainly in the field of immunology, and recently put emphasis on the development of the gene diagnostic agents. In addition, MBL continues the research and development in the field of sugar chain, which is said to be the third life chain, and lectin*1 by the team of several people for more than ten years. In collaboration with Okayama University, MBL discovered that the lectin of the seaweed Codium fragile inhibits the biofilm formation of cavity bacteria in 2010, and since then MBL has laid emphasis on the study of oral bacteria and intestinal bacteria, and the research and development in the field of the gastrointestinal tract immunity.
In recent studies, it is revealed that periodontal disease is related to various systemic diseases. The evidence has shown that many diseases including the diabetes, arteriosclerosis and premature birth are related to periodontal disease. The possibility has also been suggested that treatment of periodontal disease, one of chronic inflammation, could improve the state of diabetes.
The most leading cause of death in the nursing facility is pneumonia, and this is caused by aspiration-related pneumonia which is developed by the entrance of oral bacteria to the lungs. The average number of cavities per child was six in 1969, but decreased to around one in the recent years. On the other hand, as we reach a super aging society, oral care for elderly people becomes imperative for dentists. As shown by the 8020 campaign (to keep 20 teeth at 80 years old), it is expected that the prevention of tooth loss to keep one’s teeth for a lifetime will become the mainstream of dentistry in the future. As seen above, control of the oral bacteria is extremely important for the realization of the protracted-life society.
In addition, it is essential to have good relationship with our intestinal bacteria to maintain health. The balance between the number of good bacteria (Bifidobacterium etc.) and bad bacteria (Escherichia coli and Clostridium perfringens etc.) in our bowels is related to the deterioration of intestinal tract immunity and liver function, and furthermore the onset of cancer. There are several strains of Bifidobacterium, and to keep one’s enteral environment normally, it seems to be necessary to increase Bifidobacterium appropriate to the individual in the bowels. It is revealed that intestinal bacteria are also involved in intractable Clostridium difficile enteritis, Crohn’s disease of the inflammatory bowel disease and the ulcerative colitis. Recent reports demonstrated that many patients make the full recovery by a revolutionary experimental treatment in which fecal microbiota from a healthy individual is transplanted to a patient, and a clinical study begins in Keio University in Japan.
The enteric flora*2 (intestinal microbiota) analysis becomes low-cost and easy by the development of the next-generation sequence technology, and the time will soon come when oral bacteria and intestinal bacteria are used as an index of the health. A symbiotic relationship with intestinal bacteria is important to live a healthy and long life. MBL will contribute to health and welfare of aging society with fewer children by developing the oral care products (foods, cosmetics and quasi-drugs) using the lectin, and the new technologies for bacteria inspection and analysis.
The lectins are a type of protein which is different from antibodies and enzymes, and recognize sugar chains. Lectins exist in the wide variety of organisms including plants, animals and viruses. Each lectin recognizes different sugar chain structures, and various lectins are known to recognize specific sugar chain structures such as mannose, galactose, sialic acid and fucose. The plant lectin affects biological defense and the host specificity of root nodule bacteria. The animal lectin affects cell adhesion, morphogenesis, inflammation, and immunoreaction.
*2 Enteric flora
1012 bacteria exist per 1 gram of the human feces and recent studies revealed there are more than 400 kinds (operational classification unit OTU) of human intestinal bacteria. Since the bacteria were once classified as plants, the intestinal microbiota is also called enteric flora. Intestinal bacteria and the host affect each other, and it has been shown that the change of the constitution of enteric flora has a big influence on health and the onset of a disease. The good bacteria produce vitamins and inhibit the increase of pathogenic bacteria, but once the bad bacteria become superior, harmful effects such as excessive foul smell and the production of cancer-promoting substances appear. Many gastrointestinal drugs, foods and supplements to increase good bacteria in intestine are commercially available.