Microorganisms in the human gut can affect immune-system cells. Gut bacterial strains have been discovered that boost immune cells that have cell-killing capacity and that can target cancer and protect against infection.
The bacteria that live in our bodies have a pivotal role in the maintenance of our health, and can influence a range of conditions, such as obesity and cancer1–6. Perhaps the most important role for the community of microorganisms that live in our gut — termed the microbiota, which include bacteria, fungi and archaea — is to aid immune-system development7. Writing in Nature, Tanoue et al.8 report the identification of 11 strains of bacteria that reside in the guts of some healthy humans and that can boost immune responses that fight infection and cancer.
A particularly potent type of immune cell that recognizes and kills infected and cancerous cells is the cytotoxic CD8+ T cell. These cells identify target cells through interactions between their T-cell receptor proteins (TCRs) and peptide fragments called antigens from the target cell. Harnessing an approach used previously9,10 to identify bacterial strains that can boost certain subsets of T cell, Tanoue and colleagues used mouse models in their search for bacteria that drive production of the subset of CD8+ T cells that produce a potent immunostimulatory protein called interferon-γ (IFN-γ) and are known as CD8+ IFN-γ+ T cells. They found that mice housed under normal laboratory conditions had this type of T cell in their colons, but that such cells were mainly absent in mice raised in a germ-free environment.
Lees het hele artikel: https://www.nature.com/articles/d41586-019-00133-w