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Updated: Jan 25, 2026
Multiplexed Immunofluorescence Analysis and Quantification of Intratumoral PD-1+ Tim-3+ CD8+ T Cells
Published on: February 8, 2018
Soluble plasma programmed death 1 (PD-1) and Tim-3 in primary HIV infection
Eva Zilber1,2, Genevieve E Martin1,2, Christian B Willberg1,3
1Nuffield Department of Medicine, University of Oxford.
Abstract:
: Soluble forms of the coinhibitory receptors programmed death 1 (PD-1) and Tim-3 exist, but their relationship with T-cell surface expression remains unclear. When measured by an enzyme-linked immunosorbent assay in plasma, soluble PD-1, and soluble Tim-3 were elevated during primary HIV infection, decreased on antiretroviral therapy to levels found in controls, and correlated with cell surface expression. We conclude that soluble PD-1 and soluble Tim-3 are easy to measure biomarkers of immune exhaustion which potentially eliminate the need for flow cytometry.
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