Biomaterial vaccines to make implanted orthopedic devices safer

Biomaterial vaccines using pathogen-specific antigens could significantly lower patients’ risk of infection from implanted medical devices

Wyss Institute for Biologically Inspired Engineering at Harvard

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By Benjamin Boettner

(BOSTON) — Patients with implanted medical devices like orthopedic joint replacements, pacemakers, and artificial heart valves run a small but significant risk that these devices get infected with bacterial pathogens. This starts them on a burdensome path requiring “redo” (revision) surgeries, prolonged antibiotic treatments, or in severe cases amputation. If the infections spread in patients’ bodies, they can even become fatal.

“In the U.S. alone, about 790,000 total knee replacements and more than 450,000 hip replacements are currently performed by orthopedic surgeons, and up to 2 to 4% of those implanted devices will become infected,” said Alexander Tatara, M.D., Ph.D., an Assistant Professor at The University of Texas Southwestern Medical Center in Dallas and first-author of a new study that creates hope for the future prevention of such device infections. “These numbers alone highlight the urgency of finding effective countermeasures and bringing them to patients fast.”

Researchers have long pursued the idea that vaccines could protect patients against the pathogen Staphylococcus aureus, the leading cause of orthopedic device infection. But so far, an effective vaccine has not been produced despite much effort and several large pharma-led clinical trials.

Now, clinical researchers and bioengineers at the Wyss Institute for Biologically Inspired Engineering at Harvard University and Harvard’s John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a novel vaccine strategy with the potential to solve the challenge of device infection in patients. Their approach uses slowly biodegradable, injectable biomaterial scaffold vaccines that are equipped with immune cell attracting and stimulating molecules and S. aureus-specific antigens. Applied to a mouse model of orthopedic device infection, the vaccines created a beneficial immune response that decreased the bacterial burden about 100-fold more effectively than much shorter-lived conventional control vaccines. Biomaterial vaccines made with antigens from antibiotic-sensitive S. aureus (MSSA) bacteria also protected devices against infection from antibiotic-resistant S. aureus (MRSA) strains, making future off-the-shelf vaccines for broad use in orthopedic surgeries an attractive possibility. The findings are published in PNAS.

The study was led by Wyss Institute Founding Core Faculty member David Mooney, Ph.D.  His group at the Wyss Institute and SEAS has previously pioneered biomaterials-based vaccines as novel immunotherapies in the fight against cancer and, more recently, also to help prevent sepsis and septic shock in small and large animal models. Mooney’s team showed that these types of vaccines can activate the immune system with high efficiency against tumor cells and pathogens.

“In this study, we are seeing the type of immune responses involving specific T cell populations that might have been missing in patients vaccinated with conventional vaccines in clinical trials, in addition to S. aureus-specific antibody responses that are also produced by soluble vaccine formulations,” said Mooney. “In combination with optimized antigen collections derived from S. aureus species, our approach could lead to novel biomaterials-based vaccines with the potential to save lives and improve health outcomes for patients globally.” Mooney is the faculty lead of the Wyss Institute’s Immuno-Materials platform and also the Robert P. Pinkas Family Professor of Bioengineering at SEAS.

Protection powered by PAMPs

The biomaterial vaccines, upon their injection, provide a molecular training ground for  dendritic cells (DCs), central coordinators of the immune system that orchestrate a complex T cell response against the pathogen in nearby lymph nodes. "To specifically program DCs against infectious S. aureus bacteria, we incorporated immunogenic antigen components derived from disrupted bacteria into our vaccines, which we captured using the Wyss Institute’s FcMBL technology,” said co-author Michael Super, Ph.D., who developed the technology with Wyss Founding Director Donald Ingber, M.D., Ph.D. FcMBL is an engineered immune protein capable of binding to more than two hundred different pathogens and their glycosylated surface-exposed molecules commonly known as “pathogen-associated molecular patterns,” in short PAMPs. “In this vaccine we incorporate a diverse repertoire of hundreds of FcMBL-bound S. aureus PAMP antigens, instead of only one or few antigens contained in conventional vaccines, and enable efficient antigen transfer to DCs following injection of our vaccines into mice,” said Super, who is Wyss Institute’s Director of Immuno-Materials. 

In mice that the researchers vaccinated with their biomaterial vaccine and challenged with pathogenic S. aureus bacteria, this strategy reduced the overall bacterial burden much more potently than soluble control vaccines containing the same molecular components. “Likely by being able to engage the immune system in a sustained and highly concerted way, our biomaterial vaccines are able to activate distinct types of so-called T helper cells that start to secrete a number of protective cytokine molecules. Conventional soluble vaccines, whose molecular components quickly diffuse in the tissue they are injected in, were less efficient at this,” said Tatara, who spearheaded the project when he was a clinical research fellow in Mooney’s group at the Institute. “We will have to figure out in much more depth which parts of the immune system exactly are responsible and cooperate to bring about the protective effects,” added Tatara.

Proof of Vaccination

The team translated their observations into a mouse model of actual orthopedic device infection in which a small device is implanted into one of the animals’ hind legs and infected with a dose of pathogenic S. aureusbacteria. Five weeks prior to the surgery, they started the animals on a vaccination protocol using biomaterial and soluble control vaccines. When the researchers quantified the bacteria that managed to grow on the implanted devices, they found that their biomaterial strategy suppressed bacterial growth about 100-fold stronger than the soluble vaccine formulation.

“Importantly, we found that a biomaterial vaccine we fabricated with antigens from ‘methicillin-sensitive S. aureus’ (MSSA) strains can also protect implanted devices against later infection from methicillin-resistant (MRSA) strains, which are a big problem in hospital settings,” said Tatara. “Also trying to tease out which PAMPs stimulate the immune system the strongest opens a new avenue of research that could lead to more minimal, yet highly effective vaccines.” Mooney’s team showed that this approach could indeed be rewarding. By analyzing PAMPs from a S. aureus strain, identifying a PAMP signature, and then using one of the PAMPs as a single antigen in a biomaterial vaccine, they already could provide some level of device protection in mice. “One could envision a future in which clinical researchers rapidly identify relevant PAMPs in patient-specific S. aureus strains obtained through simple non-invasive procedures ahead of surgeries to produce effective personalized biomaterial vaccines that protect implanted orthopedic devices from infections,” said Tatara.

“This study by Dave Mooney and his team lays out an elegant and effective solution for preventing infections in patients receiving joint replacements. But beyond orthopedic implants, it could also become a versatile and easy-to-apply safeguard for many other kinds of devices dwelling for prolonged times in the human body that can create similar problems,” said Ingber, who is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Boston Children’s Hospital, and the Hansjörg Wyss Professor of Biologically Inspired Engineering at SEAS.

The study was also authored by Shanda Lightbown, Shawn Kang, Wei-Hung Jung, Hamza Ijaz, Jean Lee, and Sandra Nelson. It was supported by awards from the National Institutes of Health (award# T32 AI007061 and NIH K08 AI180362), Harvard Catalyst (award# UM1TR004408), as well as financial contributions from the Wyss Institute, and Harvard University with its affiliated academic healthcare centers.

PRESS CONTACTS

Wyss Institute for Biologically Inspired Engineering at Harvard University
Benjamin Boettner, benjamin.boettner@wyss.harvard.edu

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The Wyss Institute for Biologically Inspired Engineering at Harvard University (www.wyss.harvard.edu) is a research and development engine for disruptive innovation powered by biologically-inspired engineering with visionary people at its heart. Our mission is to transform healthcare and the environment by developing ground-breaking technologies that emulate the way Nature builds and accelerate their translation into commercial products through formation of startups and corporate partnerships to bring about positive near-term impact in the world. We accomplish this by breaking down the traditional silos of academia and barriers with industry, enabling our world-leading faculty to collaborate creatively across our focus areas of diagnostics, therapeutics, medtech, and sustainability. Our consortium partners encompass the leading academic institutions and hospitals in the Boston area and throughout the world, including Harvard’s Schools of Medicine, Engineering, Arts & Sciences and Design, Beth Israel Deaconess Medical Center, Brigham and Women’s Hospital, Boston Children’s Hospital, Dana–Farber Cancer Institute, Massachusetts General Hospital, the University of Massachusetts Medical School, Spaulding Rehabilitation Hospital, Boston University, Tufts University, Charité – Universitätsmedizin Berlin, University of Zürich, and Massachusetts Institute of Technology.

The Harvard John A. Paulson School of Engineering and Applied Sciences (http://seas.harvard.edu) serves as the connector and integrator of Harvard’s teaching and research efforts in engineering, applied sciences, and technology. Through collaboration with researchers from all parts of Harvard, other universities, and corporate and foundational partners, we bring discovery and innovation directly to bear on improving human life and society.

 

 

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.24095621 

Method of Research

Experimental study

Subject of Research

Animals

Article Publication Date

3-Nov-2025

 

Tiny iron minerals hold the key to breaking down plastic additives

Biochar Editorial Office, Shenyang Agricultural University

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Crystalline phase-dependent hydrolysis of organophosphate esters by iron oxyhydroxides: implications for nanomineral-mediated transformation of plastic additives

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Credit: Xule Pei, Zongsheng Liang, Zaihao Chen, Lin Duan, Chuanjia Jiang, Pedro J. J. Alvarez & Tong Zhang

A team of scientists has discovered that the crystal structure of naturally occurring iron minerals plays a crucial role in breaking down harmful chemical additives released from plastics. The findings could improve predictions of how these pollutants behave in the environment and guide strategies for reducing their long-term risks.

The study, published in Environmental and Biogeochemical Processes, examined how three types of iron oxyhydroxide nanominerals, goethite, akaganeite, and lepidocrocite, catalyze the breakdown of organophosphate esters (OPEs). OPEs are widely used as flame retardants and plasticizers but have been increasingly detected in air, water, and soil. Many of these compounds are known or suspected endocrine disruptors that can interfere with human and animal hormones.

“Plastic additives like OPEs are designed to improve materials but end up as invisible pollutants that persist in the environment,” said corresponding author Prof. Chuanjia Jiang from Nankai University. “Our research shows that the tiny details of mineral structure can determine how quickly and efficiently these compounds are broken down.”

Using a model compound called p-nitrophenyl phosphate, the researchers tested how efficiently each iron mineral promoted hydrolysis, a reaction that splits chemical bonds with water. The experiments revealed that all three minerals could accelerate OPE degradation under typical environmental conditions, but their effectiveness varied with crystal structure. Lepidocrocite showed the fastest reaction rate, followed by akaganeite and goethite.

Further analysis revealed that the difference arises from two competing factors: how strongly the pollutants attach to the mineral surface and how reactive the surface sites are once adsorption occurs. Akaganeite bound the pollutants most tightly, but lepidocrocite had the most chemically active sites that promoted faster bond breaking. Advanced spectroscopy and computer simulations confirmed that lepidocrocite’s surface iron atoms create stronger electric fields that pull electrons from the pollutant’s phosphorus atom, making it more vulnerable to attack by water molecules.

“This crystal-dependent behavior explains why some forms of the same mineral can be much more effective catalysts than others,” Jiang said. “It also highlights the need to consider nanoscale structure when assessing the environmental fate of pollutants.”

Because iron oxides are abundant in soils and sediments, these findings have broad implications for understanding how microplastics and their additives transform over time. As plastics weather into micro- and nanoplastics, their additives can leach out and interact with mineral surfaces, influencing both their degradation rates and potential toxicity. The study’s insights into mineral reactivity could help scientists design better remediation materials and refine models of contaminant persistence in natural systems.

The researchers note that in real-world environments, minerals can interact with natural organic matter, ions, or even change their crystal form, which may alter their catalytic abilities. Future work will explore how these complex conditions affect the breakdown of OPEs and other emerging pollutants.

The study was supported by the National Natural Science Foundation of China, the Tianjin Municipal Science and Technology Bureau, and Rice University in the United States. The collaborative team included scientists from Nankai University, Ankang University, and Rice University.

 

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Journal reference: Pei X, Liang Z, Chen Z, Duan L, Jiang C, et al. 2025. Crystalline phase-dependent hydrolysis of organophosphate esters by iron oxyhydroxides: implications for nanomineral-mediated transformation of plastic additives. Environmental and Biogeochemical Processes 1: e007  https://www.maxapress.com/article/doi/10.48130/ebp-0025-0008    

 

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About the Journal:

Environmental and Biogeochemical Processes is a multidisciplinary platform for communicating advances in fundamental and applied research on the interactions and processes involving the cycling of elements and compounds between the biological, geological, and chemical components of the environment. 

Follow us on Facebook, X, and Bluesky. 

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DOI

10.48130/ebp-0025-0008 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Crystalline phase-dependent hydrolysis of organophosphate esters by iron oxyhydroxides: implications for nanomineral-mediated transformation of plastic additives

New framework helps balance conservation and development in cold regions

Biochar Editorial Office, Shenyang Agricultural University

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Integrating ecological networks and multi-scenario optimization: a novel framework for constructing ecological security patterns

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Credit: Zhaoyang Jia, Liang Guo, Qiang Fu, Dong Liu, Xianlei Du & Song Cui

Scientists have developed an innovative planning framework that could help protect fragile ecosystems in cold regions while supporting sustainable development. The study, published in Agricultural Ecology and Environment, introduces a new “connectivity–ecological risk–economic efficiency” (CRE) approach that integrates environmental, economic, and climatic factors into a single model for ecological security planning.

Cold regions such as Northeast China’s Songhua River Basin are vital for national food production and biodiversity, yet they face mounting pressures from urban expansion, intensive farming, and climate change. Until now, most ecological planning tools have focused on either conserving habitats or reducing risks but have rarely combined connectivity, economic feasibility, and climate adaptation. The new CRE framework bridges that gap.

Led by researchers from Northeast Agricultural University, the team designed a comprehensive model that uses satellite data and advanced algorithms to identify key ecological “sources” and corridors connecting them. The approach integrates ecosystem services such as water yield, soil conservation, carbon storage, and habitat quality, while also accounting for snow cover days, a novel factor that represents the seasonal challenges unique to cold climates.

“Our goal was to create a method that not only identifies where ecosystems are most valuable but also optimizes how to protect and connect them under real-world constraints,” said corresponding author Prof. Song Cui. “By balancing ecological and economic factors, this framework helps policymakers design strategies that are both scientifically sound and cost-effective.”

Using the Songhua River Basin as a test region, the researchers found that their optimized network included nearly 500 ecological corridors spanning over 18,000 kilometers. When future development and climate scenarios were simulated, the framework revealed how conservation strategies could strengthen or weaken ecosystem connectivity. Under low-emission, ecology-focused scenarios, key habitats expanded by more than 25 percent, while high-emission scenarios led to greater fragmentation and ecological risk.

The study also introduced a new optimization process using genetic algorithms to determine the ideal width of each ecological corridor. This adjustment allows for narrower corridors that maintain ecological function but require fewer resources to protect. The results suggest that smarter design, rather than more land use, can enhance ecological resilience and reduce costs.

The team proposes a strategic spatial plan called “one barrier, two regions, multiple islands, and one center.” This concept envisions a protective ecological barrier in the west, two core ecological regions along the Songhua River, scattered habitat “islands” in the southwest, and a highly connected central hub that maintains landscape stability. Together, these zones create a blueprint for restoring and safeguarding the region’s natural infrastructure.

By combining cutting-edge modeling, network theory, and climate data, the CRE framework offers a replicable tool for ecological planning in other regions facing similar challenges. The authors emphasize that integrating such data-driven approaches into land-use and conservation policies can help balance human needs with long-term environmental security.

This research was supported by the National Key R&D Program of China and the Distinguished Youth Science Foundation of Heilongjiang Province.

 

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Journal Reference: Jia Z, Guo L, Fu Q, Liu D, Du X, et al. 2025. Integrating ecological networks and multi-scenario optimization: a novel framework for constructing ecological security patterns. Agricultural Ecology and Environment 1: e007  https://www.maxapress.com/article/doi/10.48130/aee-0025-0007   

 

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About Agricultural Ecology and Environment: 

Agricultural Ecology and Environment is a multidisciplinary platform for communicating advances in fundamental and applied research on the agroecological environment, focusing on the interactions between agroecosystems and the environment. It is dedicated to advancing the understanding of the complex interactions between agricultural practices and ecological systems. The journal aims to provide a comprehensive and cutting-edge forum for researchers, practitioners, policymakers, and stakeholders from diverse fields such as agronomy, ecology, environmental science, soil science, and sustainable development. 

Follow us on Facebook, X, and Bluesky. 

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DOI

10.48130/aee-0025-0007 

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Integrating ecological networks and multi-scenario optimization: a novel framework for constructing ecological security patterns

 

UV light holds promise for energy-efficient desalination

UCR experiments offer pathway for solar solutions

University of California - Riverside

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Luat Vuong

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Credit: UC Riverside

A team of UC Riverside researchers has uncovered a potential breakthrough in solar desalination that could reduce the need for energy-intensive saltwater treatment.

Led by Luat Vuong, an associate professor of mechanical engineering in UCR’s Marlan and Rosemary Bourns College of Engineering, the team has demonstrated for the first time how the highest frequencies of sunlight—specifically invisible ultraviolet (UV) light—can break the stubborn bonds between salt and water.

“To our knowledge, nobody else has yet articulated this deep UV channel for salt-water separation,” Vuong said. “UV light in the wavelength range of 300-400 nanometers is used for disinfection, but this deep UV channel around 200 nanometers is not well known. We may be the first to really think about how you can leverage it for desalination.”

While much work remains before practical applications are developed, the discovery provides a clear path for further research and innovation.

Published in ACS Applied Materials & Interfaces, the study by Vuong and her colleagues details how the team made a wick from aluminum nitride—a hard, white ceramic—to separate salt from water by harnessing specific light wavelengths that interact with salt water without heating the bulk liquid. Unlike traditional solar desalination methods, which rely on dark materials to absorb heat and boil water, Vuong’s approach could bypass the need for thermal processes altogether.

The experiments involved placing pairs of ceramic wicks in an enclosed chamber, with each allowed to equilibrate or adjust to similar environmental conditions. Under UV light, evaporation rates of salt water increased significantly compared to control samples kept in the dark or exposed to red, yellow, or infrared light.

“Aluminum nitride is well suited for emitting UV light due to its crystalline structure,” Vuong explained.

The material may be triggering a process called “photon upconversion,” in which low-energy photons combine into a single high-energy photon. That upconverted photon delivers a more powerful punch, potentially strong enough to break the salt-water bonds. If this upconversion process occurs without generating excess heat, which is yet to be determined, the approach could offer a non-photothermal alternative to traditional solar desalination systems that boil or heat salt water to produce vapor, which then condenses into fresh water. 

Such solar systems also could reduce the heavy electricity demands of reverse osmosis systems, which use high-pressure pumps to force salt water through membranes. The system could also address the concentrated reverse-osmosis brine waste, which is toxic to marine life when discharged into waterways.

Other potential applications for the wicking approach may be for other waste management processes, harvesting minerals in extreme environments, or replacing “swamp” coolers with salt water evaporation systems.

Still, Vuong emphasized that further research is needed before aluminum nitride-based solar desalination systems can be engineered for widespread use. 

“Other materials may be designed to be just as effective, but aluminum nitride is practical. It is inexpensive, widely available, non-toxic, highly hydrophilic, and durable,” Vuong said.

Click here for more information.
 

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Journal

ACS Applied Materials & Interfaces

DOI

10.1021/acsami.5c12331 

Method of Research

Experimental study

Article Title

Spectrum Selective Interfaces and Materials toward Nonphotothermal Saltwater Evaporation: Demonstration with a White Ceramic Wick