Human articular cartilage defects can be treated with nasal septum cells

A report from collaborating research teams from the University and the University Hospital of Basel specifies that cells isolated from the nasal septum cartilage can adapt to the environment the knee and repair articular cartilage defects. The ability of nasal cartilage cells to self-renew and adapt to the joint environment is associated with the expression of genes know as HOX genes. This research was published in the journal Science Translational Medicine in combination with reports of the first patients treated with their own nasal cartilage.

Lesions in articular or joint-specific cartilage is a degenerative that tends to occur in older people or younger athletes who engage in impact-heavy sports. Sometimes people who have experienced accidents can also suffer from cartilage lesions. Cartilage lesions present several challenges for orthopedic surgeons to repair. These surgeries are often complicated, and the recovery times are also long. However, Prof. Ivan Martin, professor of tissue engineering, and Prof. Marcel Jakob, Head of Traumatology, from the Department of Biomedicine at the University and the University Hospital of Basel have presented a new treatment option for cartilage lesions that includes the use of nasal cartilage cells to replace cartilage cells in joints.

When grown in cell culture, cartilage cells extracted from the nasal septum (also known as nasal chondrocytes) have a remarkable ability to generate new cartilage tissue after their growth in culture. In an ongoing clinical study, the Basal research group have taken small biopsies (6 millimeters in diameter) from the nasal septa of seven of 25 patients below the age of 55 years. After isolating the cartilage cells from these cartilage samples, they cultured these cells and expanded them and applied them to a three-dimensional scaffold in order to engineer a cartilage graft with a specific size (30 x 40 millimeters).

Martin and his colleagues used these very cartilage grafts to treat the cartilage lesions in human patients. After removing the damaged cartilage tissue from the knee of several patients, their knees were treated with the engineered, tailored tissue from their noses.

Two previous experiments demonstrated the potential efficacy of this procedure. First, a previous clinical study conducted in cooperation with plastic surgeons and the Basel group used the same method to successfully reconstruct nasal wings affected by tumors.

Secondly, a preclinical study with goats whose knees were implanted with nasal cartilage cells showed that these cells were not only compatible with the knee-joint, but also successfully reconstituted the joint cartilage. Lead author of this study, Karoliina Pelttari, and her colleagues were quite surprised that the implanted nasal cartilage cells, which originate from a completely different set of embryonic cell types than the knee-joint were compatible. Nasal septum cells develop from neuroectodermal cells, which also form the nervous system and their self-renewal capacity is attributed to their lack of expression of some homeobox (HOX) genes. However, these same HOX genes are expressed in articular cartilage cells that are formed by mesodermal cells in the embryo.

“The findings from the basic research and the preclinical studies on the properties of nasal cartilage cells and the resulting engineered transplants have opened up the possibility to investigate an innovative clinical treatment of cartilage damage,” says Prof. Ivan Martin about the results. Several studies have confirmed that human nasal cells maintain their capacity to grow and form new cartilage despite the age of the patient. This means that older people could also benefit from this new method, as could patients with large articular cartilage defects.

The primary target of the ongoing clinical study at the University Hospital of Basel is to confirm the safety, efficacy and feasibility of nasal cartilage grafts transplanted into joints, the clinical effectiveness of this procedure, from the data presently in hand, is highly promising.