News | Could mRNA Therapy Offer Hope for Endometrial Injury?
A Johns Hopkins University School of Medicine team recently reported in Nature Nanotechnology the first targeted delivery of therapeutic messenger RNA (mRNA) to the endometrium in mice, significantly improving embryo implantation. The work offers a potential new approach to some forms of endometrial infertility.
The Johns Hopkins Center for Nanomedicine and Wilmer Eye Institute developed a modified lipid nanoparticle (LNP) system that safely and controllably delivers mRNA to the endometrium. Abnormal endometrial structure and function contribute to several forms of female infertility, and embryos may fail to implant even with assisted reproductive technology (ART) such as IVF.
Study leader Dr Laura Ensign, professor of ophthalmology at Johns Hopkins, said there are currently no effective FDA-approved treatments for patients who remain unable to conceive with ART. “Our study lays the groundwork for exploring an entirely new standard of care.”
mRNA therapy gives cells functional instructions to make specific proteins without altering nuclear DNA. It is widely used in cancer research and COVID-19 mRNA vaccines. However, mRNA degrades easily and may be rapidly cleared or cause systemic toxicity, making localized, efficient delivery with few adverse effects a central challenge.
The therapeutic cargo encoded granulocyte-macrophage colony-stimulating factor (GM-CSF), thought to increase endometrial thickness and improve embryo attachment. Recombinant GM-CSF can be mass-produced, but its short half-life and off-target distribution limit its clinical potential.
Conventional mRNA-LNP initially spread to the liver and spleen after intrauterine administration, causing clear off-target toxicity. The team added an RGD (arginine-glycine-aspartic acid) peptide to the LNP surface. RGD binds integrin receptors highly expressed in the endometrium during the window of implantation (WOI), substantially improving endometrial targeting.
After intrauterine infusion during the WOI, RGD-modified mRNA-LNP sustained GM-CSF expression in the mouse endometrium for at least 24 hours. At 8 hours, levels were almost three times those from direct recombinant-protein injection. Blood GM-CSF was 60-fold lower in the mRNA-LNP group, indicating greatly reduced systemic exposure and potential organ toxicity.
In an infertile mouse model of human endometrial injury, untreated mice had 67% fewer implantation sites on average. Targeted mRNA-LNP treatment restored implantation to near healthy-control levels, with no clear toxicity in the uterus or other major organs.
Although human menstrual cycles differ from those of mice, Ensign noted that the implantation window is highly conserved across mammals, giving the results potential translational value.
The team plans to test additional cytokines, growth factors, and other molecules on the platform to improve reproductive outcomes. The system may also support research into endometriosis, endometrial cancer, and other endometrial disorders.
The study received funding from the National Institutes of Health (NIH) and other sources. The authors disclosed that Johns Hopkins University has filed a patent application for the mRNA-LNP technology and reported no other competing interests.
Story source:
Collected online
Published 2026-01-25
This article was prepared with AI assistance and reviewed by our editorial team before publication.
This content is for informational purposes only and does not constitute medical advice. Please consult a licensed physician. Content guidelines & editorial policy
News | Could mRNA Therapy Offer Hope for Endometrial Injury?
News | Could mRNA Therapy Offer Hope for Endometrial Injury?
A Johns Hopkins University School of Medicine team recently reported in Nature Nanotechnology the first targeted delivery of therapeutic messenger RNA (mRNA) to the endometrium in mice, significantly improving embryo implantation. The work offers a potential new approach to some forms of endometrial infertility.
The Johns Hopkins Center for Nanomedicine and Wilmer Eye Institute developed a modified lipid nanoparticle (LNP) system that safely and controllably delivers mRNA to the endometrium. Abnormal endometrial structure and function contribute to several forms of female infertility, and embryos may fail to implant even with assisted reproductive technology (ART) such as IVF.
Study leader Dr Laura Ensign, professor of ophthalmology at Johns Hopkins, said there are currently no effective FDA-approved treatments for patients who remain unable to conceive with ART. “Our study lays the groundwork for exploring an entirely new standard of care.”
mRNA therapy gives cells functional instructions to make specific proteins without altering nuclear DNA. It is widely used in cancer research and COVID-19 mRNA vaccines. However, mRNA degrades easily and may be rapidly cleared or cause systemic toxicity, making localized, efficient delivery with few adverse effects a central challenge.
The therapeutic cargo encoded granulocyte-macrophage colony-stimulating factor (GM-CSF), thought to increase endometrial thickness and improve embryo attachment. Recombinant GM-CSF can be mass-produced, but its short half-life and off-target distribution limit its clinical potential.
Conventional mRNA-LNP initially spread to the liver and spleen after intrauterine administration, causing clear off-target toxicity. The team added an RGD (arginine-glycine-aspartic acid) peptide to the LNP surface. RGD binds integrin receptors highly expressed in the endometrium during the window of implantation (WOI), substantially improving endometrial targeting.
After intrauterine infusion during the WOI, RGD-modified mRNA-LNP sustained GM-CSF expression in the mouse endometrium for at least 24 hours. At 8 hours, levels were almost three times those from direct recombinant-protein injection. Blood GM-CSF was 60-fold lower in the mRNA-LNP group, indicating greatly reduced systemic exposure and potential organ toxicity.
In an infertile mouse model of human endometrial injury, untreated mice had 67% fewer implantation sites on average. Targeted mRNA-LNP treatment restored implantation to near healthy-control levels, with no clear toxicity in the uterus or other major organs.
Although human menstrual cycles differ from those of mice, Ensign noted that the implantation window is highly conserved across mammals, giving the results potential translational value.
The team plans to test additional cytokines, growth factors, and other molecules on the platform to improve reproductive outcomes. The system may also support research into endometriosis, endometrial cancer, and other endometrial disorders.
The study received funding from the National Institutes of Health (NIH) and other sources. The authors disclosed that Johns Hopkins University has filed a patent application for the mRNA-LNP technology and reported no other competing interests.
Story source:
Collected online