TY - JOUR

T1 - The TCR ligand-inducible expression of CD73 marks γδ lineage commitment and a metastable intermediate in effector specification

AU - Coffey, Francis

AU - Lee, Sang-Yun

AU - Buus, Terkild B

AU - Lauritsen, Jens-Peter Holst

AU - Wong, Gladys W

AU - Joachims, Michelle L

AU - Thompson, Linda F

AU - Zúñiga-Pflücker, Juan Carlos

AU - Kappes, Dietmar J

AU - Wiest, David L

PY - 2014/2/10

Y1 - 2014/2/10

N2 - Numerous studies indicate that γδ T cell receptor (γδTCR) expression alone does not reliably mark commitment of early thymic progenitors to the γδ fate. This raises the possibility that the γδTCR is unable to intrinsically specify fate and instead requires additional environmental factors, including TCR-ligand engagement. We use single cell progenitor assays to reveal that ligand acts instructionally to direct adoption of the γδ fate. Moreover, we identify CD73 as a TCR ligand-induced cell surface protein that distinguishes γδTCR-expressing CD4(-)CD8(-) progenitors that have committed to the γδ fate from those that have not yet done so. Indeed, unlike CD73(-) γδTCR(+) progenitors, which largely adopt the αβ fate upon separation from the intrathymic selecting environment, those that express CD73 remain CD4(-)CD8(-) and committed to the γδ fate. CD73 is expressed by >90% of peripheral γδ cells, suggesting this is a common occurrence during development. Moreover, CD73 induction appears to mark a metastable intermediate stage before acquisition of effector function, suggesting that γδ lineage and effector fate are specified sequentially. These findings have important implications for the role of ligand in γδ lineage commitment and its relationship to the specification of effector fate.

AB - Numerous studies indicate that γδ T cell receptor (γδTCR) expression alone does not reliably mark commitment of early thymic progenitors to the γδ fate. This raises the possibility that the γδTCR is unable to intrinsically specify fate and instead requires additional environmental factors, including TCR-ligand engagement. We use single cell progenitor assays to reveal that ligand acts instructionally to direct adoption of the γδ fate. Moreover, we identify CD73 as a TCR ligand-induced cell surface protein that distinguishes γδTCR-expressing CD4(-)CD8(-) progenitors that have committed to the γδ fate from those that have not yet done so. Indeed, unlike CD73(-) γδTCR(+) progenitors, which largely adopt the αβ fate upon separation from the intrathymic selecting environment, those that express CD73 remain CD4(-)CD8(-) and committed to the γδ fate. CD73 is expressed by >90% of peripheral γδ cells, suggesting this is a common occurrence during development. Moreover, CD73 induction appears to mark a metastable intermediate stage before acquisition of effector function, suggesting that γδ lineage and effector fate are specified sequentially. These findings have important implications for the role of ligand in γδ lineage commitment and its relationship to the specification of effector fate.

KW - 5'-Nucleotidase

KW - Animals

KW - Cell Lineage

KW - Ligands

KW - Lymphopoiesis

KW - Mice

KW - Mice, Inbred C57BL

KW - Mice, Knockout

KW - Mice, Mutant Strains

KW - Mice, Transgenic

KW - Models, Immunological

KW - Precursor Cells, T-Lymphoid

KW - Receptors, Antigen, T-Cell, gamma-delta

KW - T-Lymphocyte Subsets

KW - Journal Article

KW - Research Support, N.I.H., Extramural

KW - Research Support, Non-U.S. Gov't

U2 - 10.1084/jem.20131540

DO - 10.1084/jem.20131540

M3 - Journal article

C2 - 24493796

VL - 211

SP - 329

EP - 343

JO - The Journal of Experimental Medicine

JF - The Journal of Experimental Medicine

SN - 0022-1007

IS - 2

ER -