Letter | Published:

3K3A–activated protein C stimulates postischemic neuronal repair by human neural stem cells in mice

Nature Medicine volume 22, pages 10501055 (2016) | Download Citation


Activated protein C (APC) is a blood protease with anticoagulant activity and cell-signaling activities mediated by the activation of protease-activated receptor 1 (F2R, also known as PAR1) and F2RL1 (also known as PAR3) via noncanonical cleavage1. Recombinant variants of APC, such as the 3K3A-APC (Lys191–193Ala) mutant in which three Lys residues (KKK191–193) were replaced with alanine, and/or its other mutants with reduced (>90%) anticoagulant activity, engineered to reduce APC-associated bleeding risk while retaining normal cell-signaling activity, have shown benefits in preclinical models of ischemic stroke2,3,4,5,6, brain trauma7, multiple sclerosis8, amyotrophic lateral sclerosis9, sepsis10,11, ischemic and reperfusion injury of heart12, kidney and liver13, pulmonary, kidney and gastrointestinal inflammation1,11, diabetes14 and lethal body radiation15. On the basis of proof-of-concept studies and an excellent safety profile in humans, 3K3A-APC has advanced to clinical trials as a neuroprotectant in ischemic stroke16,17. Recently, 3K3A-APC has been shown to stimulate neuronal production by human neural stem and progenitor cells (NSCs) in vitro18 via a PAR1–PAR3–sphingosine-1-phosphate-receptor 1–Akt pathway19, which suggests the potential for APC-based treatment as a strategy for structural repair in the human central nervous (CNS) system. Here we report that late postischemic treatment of mice with 3K3A-APC stimulates neuronal production by transplanted human NSCs, promotes circuit restoration and improves functional recovery. Thus, 3K3A-APC-potentiated neuronal recruitment from engrafted NSCs might offer a new approach to the treatment of stroke and related neurological disorders.

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The authors want to acknowledge the NIH grants 9R01NS090904-16 (B.V.Z.), RO1HL052246 and PO1 HL031950 (J.H.G.), R01NS75345 (S.A.G.); National Natural Science Foundation of China grant 31371116 (Y.Z.); and grants from the Adelson Medical Research Foundation, New York State Stem Cell Research Board (NYSTEM), Novo Nordisk Foundation, Lundbeck Foundation, National Multiple Sclerosis Society and ALS Association (S.A.G.).

Author information

Author notes

    • Yaoming Wang
    •  & Zhen Zhao

    These authors contributed equally to this work.


  1. Department of Physiology and Biophysics, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA.

    • Yaoming Wang
    • , Zhen Zhao
    • , Sanket V Rege
    • , Min Wang
    • , Gabriel Si
    •  & Berislav V Zlokovic
  2. The Zilkha Neurogenetic Institute, Keck School of Medicine of the University of Southern California, Los Angeles, California, USA.

    • Yaoming Wang
    • , Zhen Zhao
    • , Sanket V Rege
    • , Min Wang
    • , Gabriel Si
    •  & Berislav V Zlokovic
  3. Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, Shapingba District, Chongqing, China.

    • Yi Zhou
  4. Center for Translational Neuromedicine, University of Rochester Medical Center, Rochester, New York, USA.

    • Su Wang
    •  & Steven A Goldman
  5. Department of Neurology, University of Rochester Medical Center, Rochester, New York, USA.

    • Su Wang
    •  & Steven A Goldman
  6. Center for Basic and Translational Neuroscience, University of Copenhagen Faculty of Health and Medical Sciences, Copenhagen, Denmark.

    • Su Wang
    •  & Steven A Goldman
  7. Department of Molecular and Experimental Medicine, The Scripps Research Institute, La Jolla, California, USA.

    • John H Griffin
  8. Division of Hematology/Oncology, Department of Medicine, University of California, San Diego, San Diego, California, USA.

    • John H Griffin


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Y.W. and Z.Z. designed and performed experiments and analyzed data; Z.Z. contributed to writing the manuscript; S.V.R., M.W. and G.S. performed experiments; Y.Z. customized the Matlab program; J.H.G. and S.A.G. edited the manuscript; S.W. and S.A.G. contributed crucial materials and comments on the text; B.V.Z. designed all experiments, analyzed data and wrote the manuscript.

Competing interests

B.V.Z. is a founder of ZZ Biotech LLC, a biotechnology company with a mission to develop APC and its functional mutants for the treatment of stroke and other neurological disorders. J.H.G. is a consultant for ZZ Biotech LLC and an inventor for some uses of 3K3A-APC.

Corresponding author

Correspondence to Berislav V Zlokovic.

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