Corneal Restoration: Scientists and bureaucrats

Italian stem cells

Alexandra Bruter, <url>

A significant event occurred in February in the field of stem cell treatment. Previously, only blood stem cells were used in mass therapy. Now, for the first time, the regulatory body of a European country has approved the commercial use of another type of stem cells for the treatment of sick people.

Blood stem cells have been used for a long time: bone marrow transplantation performed to people with proliferative diseases (cancer) of blood or to people is the replacement of the patient's own blood stem cells with donor cells. The progress of this method is mainly due to two things: a more careful selection of donors and the development of methods for growing a large number of stem cells from a small one. In particular, the donor is no longer taking bone marrow, but blood from a vein, stem cells are found in the blood and they are multiplied.

Blood cells do not live long and are often updated. Therefore, blood stem cells have a proliferative potential (that is, the ability to divide) higher than other cells, and for them the task of intensive reproduction in culture was solved before anyone else.

A new therapeutic method is registered under the name Holoclar. An interview with its author, Italian Graziella Pellegrini, was published by the journal Nature (Alison Abbott, Behind the scenes of the world's first commercial stem-cell therapy). Holoclar is intended for the treatment of blindness caused by a burn.

There is a cornea on the outer surface of the eye. It is transparent, convex from the outside, and if you look from the inside of the eye, it is concave. The cornea plays the role of a collecting lens, it accounts for about two-thirds of the entire optical power of the eye. The cornea partly consists of living cells, and partly of high-molecular matrix proteins: collagen, laminin, etc. In order for the cornea to remain transparent, smooth and healthy, its cells must be renewed. Cells are renewed due to the division of stem cells located in a special niche – the corneal limb. The limb is a thin strip running along the border of the cornea and the protein membrane – the sclera (often called the eye protein).

Drawing from Wikipedia – VM

When the limb is damaged, for example, due to a burn, protein begins to build up on the cornea, vessels grow into the cornea, it loses transparency, inflammation begins, and as a result a person may lose sight, and inflammation often becomes chronic. Stem cells could improve the situation if they could repopulate the limb in the right amount.

Sometimes it turns out that not all stem cells have died, but there are too few remaining to cope with the task. It is these cells that doctors can help. For the success of the authors of the technique, an intact fragment of the limb measuring 1 by 2 mm is enough (the diameter of the cornea is about 10 mm, which means that the length of the border on which the limb is located is about 30 mm, the width of the limb is 1-1.5 mm, that is, only a few percent is enough).

The remaining intact fragment is cultured on a substrate of modified fibrin, a polymer involved in blood clotting and thrombus formation. Fibrin has two necessary properties: it is rigid, that is, the grown cells can be transferred to the eye and transplanted on such a substrate, and it degrades itself some time after transplantation; the body has special methods for the degradation of fibrin, since it often has to dissolve blood clots that have served their time.

The selection of a medium for growing cells allows them to multiply much faster than they would multiply in natural conditions with a constant inflammatory process. The authors of the technique considered a fragment containing 3,000 stem cells ready for transplantation.

The authors of the development say that every year in Europe alone, as a result of accidents, they have about a thousand new patients: people who suffered from burns, but kept part of the limb intact.

The fate of the invention was very difficult. Its authors are Italians, and they worked in Italy. There is little support for biomedical scientific developments in Italy, and it was not easy for scientists. Graziella Pellegrini and Michel de Luca started working on this topic back in 1990 in Geneva. In 1996, they moved to a Catholic hospital in Rome, but there they were not too interested in turning fundamental developments into a medicine for people, and the authors went to Venice. In 1997, the researchers published the first results: they applied the technology to the first two completely blind patients, and their vision returned. Although the authors overcame many difficulties on the way to mass clinical use, they did not give up, although many other scientists would probably have decided that this occupation was not for them, and they would rather switch to solving some other fundamental problem. To the question "Why?", Graziella Pellegrini replied in an interview that, firstly, it was her Italian character, and, secondly, she saw how people's vision returns after 20 years of blindness. How to stop after that?

In 2008, the Stefano Ferrari Center for Regenerative Medicine was organized in Modena, and the study ended there. In 2010, a larger study was published (Rama et al., Limbal stem-cell therapy and long-term corneal regeneration //N Engl J Med., 2010), which included 112 patients. 86 patients regained their eyesight, and several others experienced partial improvements.

Before the treatment method could be massively used, scientists had to solve quite a lot of individual tasks. In particular, it turned out that there are different stem cells from the limb area, and not every ratio of them guarantees success in transplantation. During the study, it turned out that the necessary stem cells can be detected by the presence of protein p63 in them. This protein is regulatory, it triggers the synthesis of certain proteins in the cell and is necessary to maintain cells in a state of stemness. The cells in which this protein was present turned out to be necessary for the restoration of vision. When there were more than 3% of protein-carrying cells among the transplanted cells, 78% of transplantations led to the restoration of vision, and when less than 3% – about 11%.

Another task that took a lot of time to solve is the creation of a substrate for growing cells that has the necessary properties. The first substrates were too fragile, and there were problems with transplantation.

This story is noteworthy not only from a scientific point of view (from a scientific point of view, the issue was resolved by the publication of 2010), but as an example of the interaction of science and society.

Here, science had something to offer society, but the whole industry is at such an early stage of development that the mechanisms for such a proposal have not been developed at all. Society wants to be sure that a scientific novelty is both safe and useful. In 2007, the European Union adopted new standards for therapeutic methods being developed. The authors have spent the last seven years in continuous communication with the relevant regulatory authorities, proving that their methods are safe and reproducible – that is, all patients are treated the same. Italian scientists are the first who managed to overcome this whole procedure and get regulatory approval for the use of their cellular technologies. Perhaps it will be easier for their followers, but even for the usual newly developed drugs, which are a chemical substance, this process can take a dozen years.

Although Italy supports the development of the biotechnology industry to a minimal extent by European standards, from time to time there are quite significant events for the industry, both positive and negative.

In Italy, a loud scandal is unfolding (and, we hope, has entered the final phase) around the Stamina Foundation. The Foundation was founded by Dr. David Vannoni in 2009 and was engaged, in fact, in quackery, offering (of course, not for free) stem cells as a cure for all diseases. They were mainly treated for neurodegenerative diseases with mesenchymal stem cells. Mesenchymal stem cells are easy to obtain, for example, from adipose tissue. The authors claimed that these cells turn into neurons and are themselves embedded in the right places. Neither the safety nor even the effectiveness of their "drugs" has ever been proven, Dr. Vannoni has never published anything similar in peer-reviewed journals. But the foundation had many supporters, even demonstrations in support were organized.

In 2013, under the influence of the scientific and medical community, the Italian government finally initiated clinical trials of the method, and in August 2014, the Turin City Court decided to confiscate equipment and cells from Stamina laboratories.

Another event related to biotechnology that occurred in Italy is positively colored. In 1992, one of the first clinical trials of gene therapy for congenital genetically determined immunodeficiency took place here. Children born with such a disease are forced to live in complete isolation and almost sterile conditions. Any encounter with an infection is fraught with death for them. The tests were successful.

Portal "Eternal youth" http://vechnayamolodost.ru10.03.2015