Cited by 282RNA Interference and Gene DeliveryErythropoietin and Anemia TreatmentRNA and protein synthesis mechanisms

Increased erythropoiesis in mice injected with submicrogram quantities of pseudouridine-containing mRNA encoding erythropoietin

Open access
Karikó, Katalin, Muramatsu, Hiromi, Keller, Jason M, Weissman, Drew·2012·Molecular Therapy

Abstract

Advances in the optimization of in vitro-transcribed mRNA are bringing mRNA-mediated therapy closer to reality. In cultured cells, we recently achieved high levels of translation with high-performance liquid chromatography (HPLC)-purified, in vitro-transcribed mRNAs containing the modified nucleoside pseudouridine. Importantly, pseudouridine rendered the mRNA non-immunogenic. Here, using erythropoietin (EPO)-encoding mRNA complexed with TransIT-mRNA, we evaluated this new generation of mRNA in vivo. A single injection of 100 ng (0.005 mg/kg) mRNA elevated serum EPO levels in mice significantly by 6 hours and levels were maintained for 4 days. In comparison, mRNA containing uridine produced 10-100-fold lower levels of EPO lasting only 1 day. EPO translated from pseudouridine-mRNA was functional and caused a significant increase of both reticulocyte counts and hematocrits. As little as 10 ng mRNA doubled reticulocyte numbers. Weekly injection of 100 ng of EPO mRNA was sufficient to increase the hematocrit from 43 to 57%, which was maintained with continued treatment. Even when a large amount of pseudouridine-mRNA was injected, no inflammatory cytokines were detectable in plasma. Using macaques, we could also detect significantly-increased serum EPO levels following intraperitoneal injection of rhesus EPO mRNA. These results demonstrate that HPLC-purified, pseudouridine-containing mRNAs encoding therapeutic proteins have great potential for clinical applications.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1038/mt.2012.7

Cites

34 of 34 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • Sequence-engineered, unmodified mRNA is competitive with nucleoside-modified mRNA with respect to protein yield in vivo.

    “In summary, these data demonstrate that sequence-engineered, unmodified mRNA is competitive with nucleoside-modified mRNA with respect to protein yield in vivo.”

    From Sequence-engineered mRNA without chemical nucleoside modifications enables an effective protein therapy in large animals (2015) · cites this paper as [27]

    The Results (page not provided) compare codon-optimized EPO mRNAs differing in whether they contain uridine or pseudouridine. In mice, the unmodified mRNA produced much lower EPO levels; 0.001 µg of pseudouridine-containing mRNA was as potent as 1 µg of unmodified mRNA in raising reticulocyte counts. This is contrary to the claimed comparable in-vivo yield. (LLM, conf=0.90)

    Checked by a reasoning model — may be wrong.

    Experimental — accuracy not yet measured
  • Two independent studies found superiority of nucleoside-modified compared to unmodified Epo mRNA.

    “Two independent studies on erythropoietin-encoding mRNA found a superiority of nucleoside-modified compared to unmodified mRNA.”

    From Sequence-engineered mRNA without chemical nucleoside modifications enables an effective protein therapy in large animals (2015) · cites this paper as [27]

    The Results (page unavailable) show that pseudouridine-modified EPO mRNA produced higher, longer-lasting EPO levels than uridine-containing EPO mRNA in mice. The Introduction mentions another study of modified mRNA for therapeutic proteins, but does not establish that it independently compared modified and unmodified EPO mRNA. This source therefore supports the superiority finding for one study, not the claim about two independent EPO studies. (LLM, conf=0.84)

    Experimental — accuracy not yet measured
  • Conclusive data have also been presented for mRNA as a platform for protein (replacement) therapies.

    “Conclusive data have also been presented for mRNA as a platform for protein (replacement) therapies (Kormann et al, 2011; Kariko et al, 2012; Zangi et al, 2013; Thess et al, 2015; Balmayor et al, 2016).”

    From mRNA mediates passive vaccination against infectious agents, toxins, and tumors (2017) · cites this paper as Kariko et al, 2012

  • Short-lived proteins can significantly profit by being expressed from mRNA (Kariko et al, 2012; Thess et al, 2015).

    “By contrast, short‐lived proteins can significantly profit by being expressed from mRNA (Kariko et al, 2012; Thess et al, 2015).”

    From mRNA mediates passive vaccination against infectious agents, toxins, and tumors (2017) · cites this paper as Kariko et al, 2012

  • The physiological effect of administering engineered Epo mRNA is as strong as that observed with pseudouridine-modified mRNA.

    “Taking into account the lower reticulocyte numbers obtained with 100 U of recombinant EPO protein as well as the lower background levels compared to a recent publication,27 the physiological effect of administering our engineered Epo mRNA is as strong as that observed with pseudouridine-modified mRNA.”

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Cited by

Sorted by citations

Authors
Karikó, K., Muramatsu, H., Keller, J. M., & Weissman, D.
Affiliations
  • University of Pennsylvania (US)
  • National Institutes of Health (US)
Corresponding author
Karikó, Katalin
Venue
Molecular Therapy
Publisher
Elsevier BV
Published
2012-05
Volume
20
Issue
5
Pages
948-953
ISSN
1525-0016 (ISSN-L)
OpenAlex
W2054412308
Cited by
282
References
34
Citations by year
2026: 10 · 2025: 15 · 2024: 22 · 2023: 27 · 2022: 35 · 2021: 30 · 2020: 17 · 2019: 14 · 2018: 16 · 2017: 17 · 2016: 25 · 2015: 24 · 2014: 11 · 2013: 13 · 2012: 6
FWCI
6.94
Type
journal article
Language
en
Open access
Locations
  • Molecular Therapy (publishedVersion, cc-by-nc-nd)
  • Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
  • PubMed Central (publishedVersion, cc-by-nc-nd)
  • PubMed (publishedVersion)
Funders
  • National Heart, Lung, and Blood Institute (R42HL087688, R42HL87688)
  • National Institute of Allergy and Infectious Diseases (R01 AI50484, R01AI050484)
  • National Institute of Neurological Disorders and Stroke (R01NS029331)
  • National Institute of Dental and Craniofacial Research (R21DE019059)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA Interference and Gene Delivery
  • Health Sciences › Medicine › Hematology › Erythropoietin and Anemia Treatment
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › RNA and protein synthesis mechanisms
Keywords
erythropoietin, in vitro transcribed mRNA, erythropoiesis, immunogenicity, reticulocyte count, hematocrit, rhesus monkeys, therapeutic protein delivery
MeSH terms
Animals, Cell Count, Chromatography, High Pressure Liquid, Erythropoiesis, Erythropoietin, Female, Genetic Vectors, Hematocrit, Humans, Injections, Intraperitoneal, Macaca mulatta, Mice, Inbred BALB C, Pseudouridine, Reticulocytes, RNA, Messenger, Drug Delivery Systems, Cell Proliferation, Mice

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review