Discover 'natural killer' in the body

Chaired by Professor Jamie Rossjohn (Monash University) and Associate Professor Andrew Brooks of the University of Melbourne (Australia), the international team of scientists has discovered the important role of ' natural killer ' cells. 'in the body's innate immune response. The results of the study are published in the journal Nature .

Professor Jamie Rossjohn

' Natural killer ' is the only and important type of white blood cell in the initial immune response to tumors and viruses. Unlike most immune system cells that are activated by molecules in pathogens or tumors, the ' natural killer ' is deactivated by a group of proteins in healthy cells. These proteins are called human leukocyte antigens (HLA). They are not found in many tumors and virus-infected cells, creating holes for the " natural killer " to attack.

The ' natural killer ' recognizes HLA molecules using an existing surveillance system called killer killer cell globulin receptors (KIR). The team identified a three-dimensional shape of one of the key KIR proteins, KIR3DL1, which binds to a particular HLA molecule. This combination plays an important role in limiting viral replication in HIV-infected people, slowing the progression of AIDS.

Professor Rossjohn believes that understanding the structure of KIR proteins can help find ways to better use ' natural killer ' cells in fighting infection.