Since their discovery in the mid-1980s, interest in the immunological significance of γδ T cells has
been subject to oscillations. The initial excitement over the unexpected discovery of a second T
cell receptor (TCR) was followed by years of uncertainty as to the biological importance of these
ambivalent T cells. Major breakthroughs led to the identification of specific and unique antigens
for the γδ TCR and accumulating evidence now shows that γδ T cells play a major role in local
immunosurveillance, thereby controlling tumorigenesis. Since 2004, biannual international γδ T
cell conferences are held to bring together experts in basic and clinical γδ T cell research. To
make accessible and synthesize the body of knowledge that has been put together, to date, we have
organized a “Research Topic” on γδ T cells consisting of a collection of original articles and focused
reviews written by leading experts in the field. The idea of this Research Focus was to present the
current status and “hot topics” as well as clinical perspectives on γδ T cell research
