The theanine content of tea may be responsible for it significantly increasing immune function in users, relative to coffee consumption. - GreenMedInfo Summary
Antigens in tea-beverage prime human Vgamma 2Vdelta 2 T cells in vitro and in vivo for memory and nonmemory antibacterial cytokine responses.
Proc Natl Acad Sci U S A. 2003 May 13;100(10):6009-14. Epub 2003 Apr 28. PMID: 12719524
Lymphocyte Biology Section, Division of Rheumatology, Immunology, and Allergy, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA.
Human gammadelta T cells mediate innate immunity to microbes via T cell receptor-dependent recognition of unprocessed antigens with conserved molecular patterns. These nonpeptide alkylamine antigens are shared by tumor cells, bacteria, parasites, and fungi but also by edible plant products such as tea, apples, mushrooms, and wine. Here we show that priming of gammadelta T cells with alkylamine antigens in vitro results in a memory response to these antigens. Such priming results also in a nonmemory response to whole bacteria and to lipopolysaccharide, characterized by IL-12-dependent secretion of IFN-gamma by gammadelta T cells and by gammadelta T cell proliferation. Drinking tea, which contains l-theanine, a precursor of the nonpeptide antigen ethylamine, primed peripheral blood gammadelta T cells to mediate a memory response on reexposure to ethylamine and to secrete IFN-gamma in response to bacteria. This unique combination of innate immune response and immunologic memory shows that gammadelta T cells can function as a bridge between innate and acquired immunity. In addition, these data provide an explanation for the health benefits of tea.
Read the entire Free Article Here
