[HTML][HTML] Extended co-expression of inhibitory receptors by human CD8 T-cells depending on differentiation, antigen-specificity and anatomical localization

L Baitsch, A Legat, L Barba, SA Fuertes Marraco… - PloS one, 2012 - journals.plos.org
L Baitsch, A Legat, L Barba, SA Fuertes Marraco, JP Rivals, P Baumgaertner…
PloS one, 2012journals.plos.org
Inhibitory receptors mediate CD8 T-cell hyporesponsiveness against cancer and infectious
diseases. PD-1 and CTLA-4 have been extensively studied, and blocking antibodies have
already shown clinical benefit for cancer patients. Only little is known on extended co-
expression of inhibitory receptors and their ligands. Here we analyzed the expression of
eight inhibitory receptors by tumor-antigen specific CD8 T-cells. We found that the majority of
effector T-cells simultaneously expressed four or more of the inhibitory receptors BTLA, TIM …
Inhibitory receptors mediate CD8 T-cell hyporesponsiveness against cancer and infectious diseases. PD-1 and CTLA-4 have been extensively studied, and blocking antibodies have already shown clinical benefit for cancer patients. Only little is known on extended co-expression of inhibitory receptors and their ligands. Here we analyzed the expression of eight inhibitory receptors by tumor-antigen specific CD8 T-cells. We found that the majority of effector T-cells simultaneously expressed four or more of the inhibitory receptors BTLA, TIM-3, LAG-3, KRLG-1, 2B4, CD160, PD-1 and CTLA-4. There were major differences depending on antigen-specificity, differentiation and anatomical localization of T-cells. On the other hand, naive T-cells were only single or double positive for BTLA and TIM-3. Extended co-expression is likely relevant for effector T-cells, as we found expression of multiple ligands in metastatic lesions of melanoma patients. Together, our data suggest that naive T-cells are primarily regulated by BTLA and TIM-3, whereas effector cells interact via larger numbers of inhibitory receptors. Blocking multiple inhibitory receptors simultaneously or sequentially may improve T-cell based therapies, but further studies are necessary to clarify the role of each receptor-ligand pair.
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