CARDIOVASCULAR
ENGINEERING
Journal for Extracorporeal Circulation, Assist Devices,Transplantation and Artificial Organs
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CARDIOVASCULAR
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Volume 1, 1996, No 1 |
Abstract:
What began 67 years ago in Sapporo through the efforts of S.
Ohno, a brave Japanese gynaecologist, became the historical
background for an unconventional rendezvous. Researchers and
clinicians from the fields of organ substitution, immunology and
transplantation joined to discuss "Immunomodulation in Human
Disorders and Organ Substitution". When Ohno in 1928 for the
first time transplanted an ovary into the retromammary position,
probably unconsciously, he opened the door to heterotopic organ
transplantation. In his original report he mentioned he had
transplanted 115 autografts and 7 allografts (1). At that time he
most likely did not even dream that he would be Dean of the
Medical Faculty of Sapporo Medical College at the time when the
son of one of his patients who was also his student would carry
out the first heart transplantation of Japan in this town (2, 3).
Twenty years ago several researchers thought that within this
century organ substitution could bring the old dream of life
prolongation closer to its fulfilment. Recently Lelkes wrote that
around the year 2050 genetic engineering will enable us to create
a "cultured replacement heart" (4). If Ohno could have
listened to the lectures at the Third World Artificial Organ,
Immunology and Transplantation Symposium (WAITS), 1995, in the
town where he pursued his life work, he probably would have
marvelled, at how far cell biology and bioengineering have come.
Even the present generation has problems in realizing that the
day may be close when organs from transgenic pigs will solve the
chronic organ donor shortage. Interim solutions will be the
bio-artificial liver, implantable artificial hearts and ingenious
methods for overcoming rejection. It may suffice to direct
attention to multilineage chimerism (5, 6),
liver-transplantation-induced immunosuppressive proteins (7) and
extracorporeal techniques for immunomodulation such as removal of
anti-HLA and anti-ABO (8) antibodies, and the removal of
xeno-antibodies (9) and photopheresis (10). The last mentioned
procedure also lessens coronary intimal thickness in transplanted
rat hearts (11). Polyclonal antibodies against donor lymphocytes
and red cells were found to impede hyperacute rejection (12). The
idea of bringing together clinicians, basic researchers and
engineers was born in 1991 in Germany by J. Wada who had
developed the first pivoting heart valve (13) in the sixties.
Cooley used this valve in the first artificial heart which he
implanted in 1969 (14). Since then new concepts of circulation
mechanics, such as finding that the blood flow through the heart
is vortical and causes concentric spiral separation of
microparticles, have been published (15). They will surely have
to be reflected in the development of artificial organs. Support
systems have already been developed which allow initiation of
femoro-femoral bypass within five minutes (16).
Liposome-encapsulated neo-red cells were already experimentally
used as perfusate for cardiopulmonary bypass (17). In the
mechanical-engineering field, besides ultrasonic motors and
linear motors also ferrofluidic actuators (18) all have potential
to drive an implantable artificial heart for long-term use. In
the fields of artificial organs and transplantation many clinical
problems have been identified, but have not yet been solved.
Complex issues such as racial differences may be involved. It is
widely known, for example that survival after liver
transplantation has markedly decreased in Hbs AG-positive Asians
(19). Clinicians hope that the newly established relationship
with immunologists and engineers will bring solutions practicable
in everyday patient care. The well-being of mankind and
artificial organs was the motto of the 32nd General Meeting of
the Japanese Society for Artificial Organs (20). At that time,
the Congress President, Dr. Y. Sezai, aptly formulated the
complexity of and the demands for the development of artificial
organs with the words: "In the process of developing
superior artificial organs and introducing them into medical use,
obviously the adequate distribution of medical resources and the
effects on the environment, as well as the relationship between
law, ethics, religion, economy and society to medicine have to be
carefully considered when carrying out research. In recent years
this necessity has become pronounced more and more." Not
only Utopians start to speculate whether new frontiers in organ
transplantation and extracorporeal immunomodulation may bring
man’s ancient dream of eternal youth closer to its
realization (21). After hearing Nosé’s lecture at Sapporo,
I am even more convinced that the advanced understanding of
circulation and the development of new materials will finally
bring the day when surgeons face the question of transplantation
or total artificial heart implantation as put forth in Assisted
Circulation 4 (22).
Address for Correspondence:
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