Abstract
Acute myeloid leukemia (AML) presents a pressing medical need in that it is largely resistant to standard chemotherapy as well as modern therapeutics, such as targeted therapy and immunotherapy, including anti–programmed cell death protein (anti-PD) therapy. We demonstrate that programmed death-1 homolog (PD-1H), an immune coinhibitory molecule, is highly expressed in blasts from the bone marrow of AML patients, while normal myeloid cell subsets and T cells express PD-1H. In studies employing syngeneic and humanized AML mouse models, overexpression of PD-1H promoted the growth of AML cells, mainly by evading T cell–mediated immune responses. Importantly, ablation of AML cell-surface PD-1H by antibody blockade or genetic knockout significantly inhibited AML progression by promoting T cell activity. In addition, the genetic deletion of PD-1H from host normal myeloid cells inhibited AML progression, and the combination of PD-1H blockade with anti-PD therapy conferred a synergistic antileukemia effect. Our findings provide the basis for PD-1H as a potential therapeutic target for treating human AML.
Authors
Tae Kon Kim, Xue Han, Qianni Hu, Esten N. Vandsemb, Carly M. Fielder, Junshik Hong, Kwang Woon Kim, Emily F. Mason, R. Skipper Plowman, Jun Wang, Qi Wang, Jian-Ping Zhang, Ti Badri, Miguel F. Sanmamed, Linghua Zheng, Tianxiang Zhang, Jude Alawa, Sang Won Lee, Amer M. Zeidan, Stephanie Halene, Manoj M. Pillai, Namrata S. Chandhok, Jun Lu, Mina L. Xu, Steven D. Gore, Lieping Chen
Figure 5
Anti-human PD-1H mAb reverses immune evasion induced by human AML surface PD-1H.
Copyright © 2026 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)