Volume 21 — OUR PROGRESSING KNOWLEDGE OF LIFE SURGERY PERPETUATES THE BODY'S ORGANS

A.D. 1912

GENEVIEVE GRANDCOURT Prof. R. LEGENDRE

Several years ago a wealthy Swedish manufacturer of dynamite left, by his will, a fund for the providing of a large prize to be conferred each year upon the person who has accomplished most for the peaceful progress of mankind. This annual sum of forty thousand dollars, which is called from its donor the "Nobel prize," was, in October, 1912, conferred upon a surgeon, Dr. Alexis Carrel, for his remarkable work in the study of the life of the tissues and organs which exist in the human body.

Even before this public recognition of his work, Dr. Carrel had in the summer of 1912 created a furor among the savants of Paris by the announcement of what he had accomplished. Carrel, though a native-born Frenchman, is an American by education and citizenship, and the French were at first inclined to challenge the value of his work. We therefore present here a "popular" scientific account of what he had achieved, reprinted by permission from the Scientific American. Then comes the grudging approval of Professor Legendre, the noted "Preparator of Zoology," head of that section in the National Museum of Paris.

Briefly stated, the impressive step which science has here taken, is the preservation of life in the heart and other organs so that these may be taken out of the body and yet kept alive for months. With smaller animals Carrel has even accomplished the actual transferrence of organs from one individual to another. As for the simpler bodily tissues, it now seems possible to preserve these indefinitely outside the body, not only alive but in excellent health and ready to reassume their functions in another body.

GENEVIEVE GRANDCOURT

THE "IMMORTALITY" OF TISSUES

A very evident disadvantage under which medical science has labored has been the impossibility of watching the chemical process set in motion by substances introduced into the body. For this reason various experimenters, from time to time, have attempted to "grow tissues" artificially, in such manner that their development, functions, and decay—under both healthy and diseased conditions—might be studied under the microscope. The only way in which this could be done would be to take a piece of living tissue from the body, and cause its cells to multiply; tissue being made up of an aggregation of cells.

Science has failed to produce a single living cell, that is, a cell which will undergo the process of nuclear division (growth) which is the prime condition of its being; and it seemed equally impossible to cause a cell already living to undergo the same process if deprived of the circulation of the blood. Therefore, when in 1910 it was announced that Dr. Alexis Carrel with his assistant, Dr. M. T. Burrows, had succeeded, scientific credulity was taxed. A well-known French savant expressed the opinion before the Society of Biology in Paris, that as others experimenting along these lines, had witnessed only degeneration and survival of cells, this phenomenon was all Carrel's discovery amounted to. In view of past experience, indeed, the chances were in favor of a mistake. In 1897, Leo Loeb said that he had produced this artificial growth both within and without the body. Obviously, such development within the organism where the process of utilizing the body-fluids, etc., follows the same course as in nature, takes on the character of grafting rather than of cultivating in a culture medium. As to causing the external growth, it was ten years later before it seems first to have succeeded. In 1907 Harrison, from Johns Hopkins University, furnished details of his research in such form as to be convincing. But his work had reference to the growth of tissues only of coldblooded animals, he having cultivated artificially, nerve fibers from the central nervous system of the frog.

Carrel's work consisted in extending Harrison's method to apply to warm-blooded animals, including, of course, mammals; he having primarily in view at this time a more precise knowledge of the laws governing the restoration of tissues, for example, after serious surgical wounds. He and his assistant worked steadily to this end, and succeeded. The tissues of the higher animals, including man, can now be developed in a culture, and such development can be made to correspond to a rigidly precise technique. The feat is accomplished by putting minute pieces of living tissue into a plasmatic (blood) medium which will coagulate. So complicated is this apparently simple matter in its application that only the most exquisite surgical skill is proof against incalculable modifications in results.

Having obtained evidence that tissue can be cultivated in accordance with a formula that may be relied upon to give definite results, the effort was made to grow artificially the various malignant (cancerous) tissues, in turn, of chicken, rat, dog, and human being. Cancerous tissue invariably developed cancer, and so rapidly and extensively that the growth could be observed with the naked eye.

It now became evident that, under the right circumstances, the artificial growth of tissues could be utilized in the study of many problems; such as malignant growth of tissue; certain problems in immunity, as, for example, the production of antitoxins of certain organisms; the regulation of the growth of the organism, or of different parts of the organism; rejuvenation and senility; and the character of the internal secretions of the glands, such as the thyroid which plays a role most important in physical and mental development. The difficulty lay in the fact that the artificial growth was so very short-lived. It was found that by passing the growth into a new medium, and repeating the process, the tissues would begin to grow again; but their life even under these circumstances was limited at the most to twenty days. This was manifestly too short a time in which to study the fundamental questions to which the researchers had addressed themselves. Thereupon, study was taken up to determine the question as to what made these tissues die. It was found that, apparently as incidental to growth, there was the process of decay, due to an inability of the tissues to eliminate waste products.

On January 17, 1912, experiments were commenced to determine whether these effects could be overcome. The observations were on the heart and blood-vessels, artificially grown, of the chicken fetus. These growths were put into a salt solution for a few minutes at different periods of their growth, and then placed in a new plasmatic medium. It was found that by following this method, the tissues could be made to live indefinitely. When an animal is in the early stages of its development, the growth of its tissues is necessarily greater as it matures, there being steady diminution after a certain age until the growth altogether ceases, and the size of the animal is determined. But it was found by subjecting these artificial growths to washings in salt solution that the mass was fifteen times greater at the end of than at the commencement of the third month, showing that they do not grow old at all! In the artificial growth the problem of senility and death is solved.

It was the announcement of this "permanent life of tissues" that caused such a furor in Paris last summer, and several eminent scientists to demand ocular demonstration, because "the discovery, if true, constituted the greatest scientific advance of a generation."

The following summary of this interesting and vitally important and epoch-making work of Carrel is translated from an article published in Paris recently by Professor Pozzi, who witnessed the experiments:

"Carrel found that the pulsations of a fragment of heart, which had diminished in number and intensity or ceased, could be revived to the normal state by a washing and a passage. In a secondary culture, two fragments of heart, separated by a free space, beat as strongly and regularly. The larger fragment contracted 92 times a minute and the smaller 120 times. For three days, the number and intensity of the pulsations varied slightly. On the fourth day, the pulsations diminished considerably in intensity. The large fragment beat 40 times a minute and the little fragment 90 times. The culture was washed and placed in a new medium. An hour and a half after, the pulsations had become very strong. The large fragment contracted 120 times a minute and the small fragment 160 times. At the same time the fragments grew rapidly. At the end of eight hours they were united and formed a mass of which all the parts beat synchronically."

Experiments to date seem to establish that the connective tissue, at any rate, is "immortal."

From this research, it is possible to arrive at certain logical conclusions, which, however, it remains for the future to confirm. One, and the most important, is that the normal circulation of the blood does not succeed in freeing all the waste products of the tissues, and that this is the cause of senility and death. Were science to find some way to wash the tissues in the living organism as they have been washed in these cultures, man's life might be indefinitely prolonged.

R. LEGENDRE

The Nobel prize in medicine for 1912 has just been awarded to Dr. Alexis Carrel, a Frenchman, of Lyon, now employed at the Rockefeller Institute of New York, for his entire work relating to the suture of vessels and the transplantation of organs.

The remarkable results obtained in these fields by various experimenters, of whom Carrel is most widely known, and also the wonderful applications made of them by certain surgeons have already been widely published.

The journals have frequently spoken lately of "cultures" of tissues detached from the organism to which they belonged; and some of them, exaggerating the results already obtained, have stated that it is now possible to make living tissues grow and increase when so detached.

Having given these subjects much study I wish to state here what has already been done and what we may hope to accomplish. As a matter of fact we do not yet know how to construct living cells; the forms obtained with mineral substances by Errera, Stephane Leduc, and others, have only a remote resemblance to those of life; neither do we know how to prevent death; but yet it is interesting to know that it is possible to prolong for some time the life of organs, tissues, and cells after they have been removed from the organism.

The idea of preserving the life of greater or lesser parts of an organism occurred at about the same time to a number of persons, and though the ends in view have been quite different, the investigations have led to essentially similar results. The surgeons who for a long time have transplanted various organs and grafted different tissues, bits of skin among others, have sought to prolong the period during which the grafts may be preserved alive from the time they are taken from the parent individual until they are implanted either upon the same subject or upon another. The physiologists have attempted to isolate certain organs and preserve them alive for some time in order to simplify their experiments by suppressing the complex action of the nervous system and of glands which often render difficult a proper interpretation of the experiments. The cytologists have tried to preserve cells alive outside the organism in more simple and well-defined conditions. These various efforts have already given, as we shall see, very excellent results both as regards the theoretical knowledge of vital phenomena and for the practise of surgery.

It has been possible to preserve for more or less time many organs in a living condition when detached from the organism. The organ first tried and which has been most frequently and completely investigated is the heart. This is because of its resistance to any arrest of the circulation and also because its survival is easily shown by its contractility. In man the heart has been seen to beat spontaneously and completely 25 minutes after a legal decapitation (Renard and Loye, 1887), and by massage of the organ its beating may be restored after it has been arrested for 40 minutes (Rehn, 1909). By irrigation of the heart and especially of its coronary vessels the period of revival may be much prolonged.

The first experiments with artificial circulation in the isolated heart were made in Ludwig's laboratory, but they were limited to the frog and the inferior vertebrates. Since then experiments on the survival of the heart have multiplied and become classic. Artificial circulation has kept the heart of man contracting normally for 20 hours (Kuliabko, 1902), that of the monkey for 54 hours (Hering, 1903), that of the rabbit for 5 days (Kuliabko, 1902), etc. It has also enabled us to study the influence upon the heart of physical factors, such as temperature, isotonia; chemical factors, such as various salts and the different ions; and even complex pharmaceutical products. Kuliabko (1902) was even able to note contractions in the heart of a rabbit that had been kept in cold storage for 18 hours, and in the heart of a cat similarly kept after 24 hours. The other muscular organs have naturally been investigated in a manner analogous to that which has been used for the heart; and for the same reason, because it can be readily seen whether or not they are alive. The striated muscles survive for quite a long time after removal, especially if they are preserved at the temperature of the body and care is taken to prevent their drying. By this method many investigations have been made of muscular contractions in isolated muscles. Landois has noted that the muscles of a man may be made to contract two hours and a half after removal, those of the frog and the tortoise 10 days after. Recently Burrows (1911) has noted a slight increase in the myotomes of the embryo chick after they have been kept for 2 to 6 days in coagulated plasma.

Non-muscular organs may also survive a removal from the parent organism, but the proofs of their survival are more difficult to establish because of the absence of movements. Carrel (1906) grafted fragments of vessels that had been in cold storage for several days upon the course of a vessel of a living animal of the same species; in 1907 he grafted upon the abdominal aorta of a cat a segment of the jugular vein of a dog removed 7 days previously, also a segment of the carotid of a dog removed 20 days before; the circulation was reestablished normally; these experiments have, however, been criticized by Fleig, who thinks that the grafted fragments were dead and served merely as supports and directors for the regeneration of the vessels upon which they were set. In 1909 Carrel removed the left kidney from a bitch, kept it out of the body for 50 minutes, and then replaced it; the extirpation of the other kidney did not cause the death of the animal, which remained for more than a year normal and in good health, thus proving the success of the graft. In 1910 Carrel succeeded with similar experiments on the spleen.

Taken altogether, these experiments show that the greater part, if not all, of the bodily organs are able to survive for more or less time after removal from the organism when favorable conditions are furnished. There is no doubt but what the observed times of survival may be considerably prolonged when we have a better knowledge of the serums that are most favorable and the physical and chemical conditions that are most advantageous.

If we can preserve the organs, we may expect to also keep alive the tissues and cells of which they are composed. Biologists have studied these problems, too, and have also obtained in this department some very interesting results.

The cells which live naturally isolated in the organism, such as the corpuscles of the blood and spermatozoa, were the first studied. Since 1910 experiments on the survival of tissues have multiplied and at the same time more knowledge has been obtained concerning the conditions most favorable to survival and the microscopical appearances of the tissues so preserved. In 1910 Harrison, having placed fragments of an embryo frog in a drop of coagulated lymph taken from an adult, saw them continue their development for several weeks, the muscles and the epithelium differentiating, the nervous rudiments sending out into the lymph filaments similar to nerve fibers. Since 1910 with the aid of Dr. Minot, I have succeeded in preserving alive the nerve cells of the spinal ganglia of adult dogs and rabbits by placing them in defibrinated blood of the same animal, through which there bubbled a current of oxygen. At zero and perhaps better at 15°-20°, the structure of the cells and their colorable substance is preserved without notable change for at least four days; moreover, when the temperature is raised again to 39°, certain of the cells give a proof of their survival by forming new prolongations, often of a monstrous character. At 39° some of the ganglion cells which have been preserved rapidly lose their colorability and then their structure breaks up, but a certain number of the others form numerous outgrowths extremely varied in appearance. We have, besides, studied the influence of isotony, of agitation, and of oxygenation, and these experiments have enabled me to ascertain the best physical conditions required for the survival of nervous tissue. In 1910, Burrows, employing the technique of Harrison, obtained results similar to his with fragments of embryonic chickens. Since 1910 Carrel and Burrows applied the same method to what they call the "culture" of the tissues of the adult dog and rabbit; they have thus preserved and even multiplied cells of cartilage, of the thyroid, the kidney, the bone marrow, the spleen, of cancer, etc. Perhaps Carrel and his collaborators may be criticized for calling "culture" that which is merely a survival, but there still remains in their work a great element of real interest.

Such are, too briefly summarized, the experiments which have been made up to the present time. We can readily imagine the practical consequences which we may very shortly hope to derive from them, and the wonderful applications of them which will follow in the domain of surgery. Without going so far as the dream of Dr. Moreau depicted by Wells, since grafts do not succeed between animals of different species, we may hope that soon, in many cases, the replacing of organs will be no longer impossible, but even easy, thanks to methods of conservation and survival which will enable us to have always at hand material for exchange.

The dream of to-day may be reality to-morrow.

There are also other consequences which will follow from these researches. I hope that they will permit us to study the physical and chemical factors of life under much simpler conditions than heretofore, and it is toward this end that I am directing my researches. They will enable us to approach much nearer the solution of the old insoluble problem of life and death. What indeed is the death of an organism all of whose parts may yet survive for some time?

These, then, are the researches made in this domain, fecund from every point of view, and the great increase in the number of experts who are taking them up, while it is a proof of their interest, gives hope for their rapid progress.