New research by an interdisciplinary team in Lithuania has revealed a promising and unconventional approach to cartilage regeneration. Using extracellular vesicles derived from menstrual blood stromal cells, the researchers demonstrated their potential to stimulate cartilage repair – paving the way for a future cell-free therapy for osteoarthritis.

More than 600 million people worldwide live with osteoarthritis, with around 73 per cent over age 55 and 60 per cent being female. With ageing populations, rising obesity, and more injuries, osteoarthritis’s prevalence will keep growing.
Today’s clinical treatments mainly manage symptoms such as pain and inflammation, but none can halt or reverse cartilage degeneration. Regenerative medicine, based on the principles of stem cell technology and tissue engineering to replace or regenerate human tissues and organs and restore their functions, is therefore gaining momentum. Among the strategies, menstrual blood-derived cells have emerged as a more promising tool than bone marrow cells.

“Collecting menstrual blood is non-invasive and simple, since it is a naturally shed biological material. In contrast, collecting bone marrow requires an invasive procedure. Furthermore, these cells actively secrete molecules that promote regeneration to regenerate the uterine lining every month. This makes them an attractive source for regenerative medicine, particularly when safety and accessibility are paramount,” says Dr Ilona Uzielienė, a researcher at Kaunas University of Technology (KTU), Faculty of Chemical Technology.

Therapy worked even on older cells with reduced regenerative capacity

A study by Lithuanian scientists from the biomedicine and chemistry fields explored the potential of extracellular vesicles (EVs) from menstrual blood-derived mesenchymal stromal cells. According to Dr Uzielienė, EVs are tiny messenger-like particles released by cells that can enter other cells and influence their activity – for example, by promoting regeneration or reducing inflammation.

In the experiment, researchers used menstrual blood samples from three healthy donors, as well as post-surgical tissue samples from ten female donors with osteoarthritis. To observe how EVs affect human tissue, the scientists used biological scaffolds – structures that help stabilise EVs and support their interaction with cells.

“What surprised us most was that the therapy worked even in cartilage cells from older postmenopausal women, whose natural regenerative capacity is already greatly reduced. Despite this, extracellular vesicles from menstrual blood cells not only improved cartilage cell function and slowed tissue degradation but also increased progesterone receptor expression in the older cartilage cells, where only minimal traces would normally remain,” says Dr Uzielienė.
According to her, the main innovation of this study is its proposal of a cell-free therapy – one that is based not on the cells themselves, but on their tiny particles, extracellular vesicles. They can activate regeneration without any side effects.

Biomimetic scaffolds, essential part of the therapy

Because these vesicles are fragile and degrade quickly, researchers are developing biological scaffolds that can protect them and release them gradually when the joint is under pressure or in motion. This could prolong their effects, improve treatment outcomes, and create new possibilities for cartilage repair and osteoarthritis therapy.

“While building biomimetic scaffolds, the biggest challenge is that a biomedical material must excel in all areas simultaneously – it must be chemically stable, mechanically robust, biologically compatible and practically manufacturable. This is particularly complex in the case of cartilage, as both the natural architecture and resistance to mechanical stress must be replicated,” says Dr Edvinas Krugly, a senior researcher at KTU Faculty of Chemical Technology.

According to him, regenerative medicine depends on interdisciplinary collaboration. A chemist may develop a new material, but without cell biologists, physicians, and experts from bioengineering and pharmacy, it is impossible to fully understand its effects, clinical relevance, or practical potential.

“What drew me to this field was a desire to develop new methods of research and treatment. However, a new treatment method does not necessarily mean creating a new medicine. Sometimes, a breakthrough occurs when we develop a new material or platform that enables drugs, cells, or vesicles to be delivered more precisely, safely, and effectively,” says Dr Krugly.

Biomimetic materials help researchers better recreate the natural tissue environment, extend the activity of bioactive molecules, and advance regenerative medicine. In this context, the biomimetic scaffold is not just a support, but an essential part of the therapy itself.