Soluble PD-L1 generated by endogenous retroelement exaptation is a receptor antagonist.
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ABSTRACT:
SUBMITTER: Ng KW
PROVIDER: S-EPMC6877088 | biostudies-literature | 2019 Nov
REPOSITORIES: biostudies-literature
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Soluble PD-L1 generated by endogenous retroelement exaptation is a receptor antagonist.
Ng Kevin W KW Attig Jan J Young George R GR Ottina Eleonora E Papamichos Spyros I SI Kotsianidis Ioannis I Kassiotis George G
eLife 20191115
Immune regulation is a finely balanced process of positive and negative signals. PD-L1 and its receptor PD-1 are critical regulators of autoimmune, antiviral and antitumoural T cell responses. Although the function of its predominant membrane-bound form is well established, the source and biological activity of soluble PD-L1 (sPD-L1) remain incompletely understood. Here, we show that sPD-L1 in human healthy tissues and tumours is produced by exaptation of an intronic <i>LINE-2A</i> (<i>L2A</i>) ...[more]
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