Immune checkpoint inhibition targeting T cells has shown tremendous promise in the treatment of many cancer types and are now standard therapies for patients. While standard therapies have focused on PD-1 and CTLA-4 blockade, additional immune checkpoints have shown promise in promoting anti-tumor immunity. PSGL-1, primarily known for its role in cellular migration, has also been shown to function as a negative regulator of CD4(+) T cells in numerous disease settings including cancer. PSGL-1 is highly expressed on T cells and can engage numerous ligands that impact signaling pathways, which may modulate CD4(+) T cell differentiation and function. PSGL-1 engagement in the tumor microenvironment may promote CD4(+) T cell exhaustion pathways that favor tumor growth. Here we highlight that blocking the PSGL-1 pathway on CD4(+) T cells may represent a new cancer therapy approach to eradicate tumors.

Author Info: (1) Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States. (2) Department of Molecular Biology and Biochemistry, University

Author Info: (1) Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States. (2) Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States. (3) Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States. (4) Department of Molecular Biology and Biochemistry, University of California, Irvine, Irvine, CA, United States.