The production of tissue grafts - What does a  tissue bank do?

Tissue medicine 

More than 10,000 patients are waiting for a tissue transplant, and the trend is rising. As a result, tissue medicine is becoming a whole-society task and challenge in Germany. Tissue medicine is a major part of transplant medicine. Despite all progress in medicine, the only alternative to treating their disease and rehabilitation is still the transplantation of tissue for many patients. The demand for high-quality tissue transplants has increased significantly in Germany in recent years. Tissue medicine is divided into the areas of tissue donation, processing, allocation and transplantation. 

In contrast to organ donation, the tissue (transplants) are not transplanted immediately.


Tissue Bank
In the tissue bank, high-quality tissue transplants are produced from the donated and retrieved tissues. For the production of the tissue graft, various methods are used, the methods for the production of classical standard tissue preparations as well as those of regenerative medicine (decellularisation).


Tissue Transplants


Cornea transplantation is the oldest and most frequent transplantation at all. Approx. 6000 transplants (keratoplasty) are performed in Germany every year. The need for cornea has risen in recent years due to new surgical techniques and is almost twice as large today. 

The eye is the gate to the world and the cornea of the eye the windscreen. An evenly curved and completely clear cornea leads to a clear vision. Diseases of the cornea (corneal curvatures or corneal opacities) can affect the view of the world and ultimately lead to blindness through untreated visual acuity. In addition to modern methods of corneal surgery, corneal transplantation can save patients from blindness or improve their vision and thus open the door to the world. Indications for a transplantation are, for example, injuries or scarring on the cornea after accidents, infections or burns. 

In the case of perforating keratoplasty, the opaque diseased cornea of the patient is replaced by a clear healthy donor cornea. For certain diseases of the corneal endothelium (the innermost layer of the cornea), the complete cornea does not have to be transplanted. It is enough to replace the diseased corneal endothelium (posterior lamellar keratoplasty - DMEK). 

By deep anterior lamellar keratoplasty, the corneal stroma is removed recessing the endothelium. As a result, the deep corneal nutrient layer is retained. Then a corresponding donor disc is sewn into the gap.


Heart Valves
Damage to the heart valves is a common disease pattern in our society and the result of calcifications, infections or heart attacks. Damaged heart valves can lead to a functional weakness of the heart in the long term, which dramatically reduces the performance of those concerned. A therapy option is the replacement of the heart valve by a transplant.


Blood Vessels
Narrowing vessels in the course of life due to calcification or clogging altogether, can be life threatening and lead to a heart attack. On the legs, vessel narrowings or blockages lead to pain and restricted range of movement (peripheral arterial occlusive disease), in advanced cases the amputation is threatened. In vascular surgery, human blood vessels are used to replace narrowed or blocked blood vessels (bypass surgery). Transplants are also used for vessel reconstruction, especially for the replacement of infected artificial prostheses. The latter are often life-saving emergency operations.

The skin as the largest organ of man protects it from harmful effects such as heat, cold, infections or rays. Smaller defects can be regenerated by itself without problems. In the case of large-area destruction of the skin, e.g. by burns or by tumor-related and chronic non-healing wounds, this self-healing does not suffice. A covering of the affected skin parts with donor skin grafts can be life-retentive in such cases. Dermis transplants, produced from postmortal donated tissue, can temporarily cover the damaged areas and form a basis for tissue generation. Infections and fluid losses are prevented as well as the healing of larger wounds and ulcers made possible.

Amniotic Membrane
The amniotic membrane is the thin, vessel-free innermost layer of the placenta, which protects the embryo in the mother's body and is retrieved under sterile conditions during a Caesarean sectio as so-called live donation after the consent of the childbearing.
The amniotic membrane is used in ophthalmology for the treatment of surface defects of the conjunctiva (corneal conjunctival diseases) and of the cornea of the eye (corneal ulcers, corneal perforations), for the latter mostly temporarily until a cornea transplant can be applied. These defects might be caused by accidents or as a result of eye diseases. This therapy is also chosen for burns in order to heal the destroyed surface of the cornea. 

The amniotic membrane is transplanted to the entire surface of the cornea in the treatment of the injured cornea. Underneath this wound cover the corneal lesion is allowed to heal and to regenerate. The initially opaque amniotic membrane usually clears over time and allows the patient to have a good vision. After about a month, the amniotic membrane dissolves and is overgrown by the patients own cells. Since the amniotic membrane has healing and analgesic properties, its further use is in wound treatment , for example, of chronic wounds and burn victims.


Bones, Tendons, Ligaments and Fasciae
the bony skeleton provides the shape of the body. It is moved by the skeletal muscles. Tendons form the endings of the skeletal muscles and serve their approach to the bone and thus the transmission of force between the muscles and the skeletal system.
Ligaments fix movable parts of the skeleton against one another and are therefore essential components of the joints or joint capsules. They limit the mobility to the physiologically desirable level and ensure functional stability.
The fasciae envelope individual organs, muscles or muscle groups. The Fascia lata, for example, surrounds the muscular mass of the thigh. The various tissue preparations from bones, tendons, ligaments and Fascia lata have a very broad range of applications. For example they can help to heal accident- or surgery-related damage, to replace corresponding components of the musculoskeletal system after their loss reconstructively, to avoid amputations, to maintain the mobility of joints and to restore or to close defects or perforations.