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Life is not yet a machine which can be disassembled freely.

作者:Xu Rongxiang 出版社:CHINA SOCIAL SCIENCES PRESS 发行日期:2009 September

In stem cell research, the difference between in vitro and in vivo mode reflected not only the different understanding between western and eastern researchers on stem cell activities, but also the difference on the in depth recognition on the nature of life.  Inspired by molecular biology, in vitro researchers observed life activities with a mechanistic point of view, which had dominated the understanding of life since 20th century; the success of Rongxiang Xu’s MEBT techniques and the emergence of in situ stem cell culture slightly retrogressed people’s understanding on life nature from today back to the history.  When the whole world is mesmerizing in the hope of revealing the mystery of life, and extremely appraising people’s recognition ability, Rongxiang Xu showed the world the other side – potential of life itself.  This revelation is not merely a demonstration.  It offered an implicational feeling to the people as God given. Rongxiang Xu, at the frontline, in the research field in which human power was expressed to the extreme, at the most imaginative and proudest moment, with his ancient eastern intelligence fulfilled the unreachable dream which could not be fulfilled even with all human intelligence combined.  It is incredible, like God was joking and playing the cat and mouse with human being.  What is the meaning behind Rongxiang Xu and his research results?  Is there a supernatural power manipulating its creation, challenging human’s intelligence, and sneering at the human vulnerability?

In 1912, Germany born biologist Loeb published his epoch-making book, ‘The Mechanistic Conception of Life’ when migrating to America.  In the book he described his own experiment on the eggs of sea urchin.  Loeb took the eggs out of female sea urchin and without sperm, used chemicals to stimulate female urchin to mimic fertilization, and therefore produced the most surprising phenomenon – the generation of an ‘embryo’.  Although today this experiment becomes a simple demonstration to show the early development of embryo, back to that time, this process of monocellular development into organism was described on newspaper headline as production of life in the test tube.  Loeb’s study and discovery became the clear evidence to support the mechanistic conception of life.  He truly believed that the mechanisms of life were as easy as that life could be produced in laboratory.  He wrote: “We will successfully produce artificial life; even not, we will find the reason.”

Since 1970s, the research in life activities had been carried out on the cell and molecule combination level to explore the nature of life with mechanistic approach.  Today, some life activities can be performed without organism, and the fundamental process of life could be explained by the interaction between nonliving atoms and molecules.  Contemporary biologists claimed: “All life building phenomena can be explained by physics and chemistry vocabularies.”

By the success of life cloning from somatic cells and indefinite proliferation through in vitro stem cell culture, mechanistic understanding of life was pushed to the extreme.  It was reported that the study groups in American and Canada had announced to initiate an ambitious plan with 3 billion British pounds of budget to produce human organs.  They would clone the various tissues of the organ first, and then assemble the tissues to form the organ.  For example, to produce a heart, firstly they would use stem cells from different tissues to produce cardiac muscle, heart valve, and blood vessel tissues, and then put these tissues together to form a heart.  The target organs included heart, kidney, and liver, etc.

In history, although some western scientists realized the ‘self constitution’ ability of life, it was used, instead of supporting organicism, only for describing life dynamics which could not be explained by their mechanisticism.  When facing life dynamics, their explanation was that it was unnecessary to explain it, like the formation of snow flake, which was not by miracle.  The snow flake crystallization was originated by some specific features of molecules.  It was self constitution without influence of external factors.  Specific molecules could form specific structures because their physical and chemical properties only allow them to form those structures.  In other words, the crystallization was caused by the internal factors inside the molecules without the influence of external factors.  The French Nobel Prize winning biologist Monod wrote in his book ‘Chance and Necessity’: “Pre-constituted complete structures do not exist, but their blueprints are stored in each constitution unit, thus, without external help or inserted extra information, they can be formed automatically and spontaneously.  The essential information is partially concealed in the forming molecules, and a structure is formed gradually instead of suddenly from nothing.  It is the demonstration of the message.”

From global to local, from macrocosmic to microcosmic, the understanding on life nature was gradually expanded.  It was fundamentally improved from the superficial level into the intrinsic level.  The life nature was successively revealed on organism – system – organ – tissue – cell level.  The understanding was guided further into microcosmic level on which people was inspired by the discovery of ‘life mechanistic’ details without noticing the macrocosmic level, let alone the inevitable correlation between microcosmic and macrocosmic level.  It seemed that all of the significance of life activities lay on the microcosmic level and in the cells; even the occasional consideration about the association between molecules and external environment was focused on microenvironment.

Microcosmically, organism is a macro-system.  Its life activities are complicatedly and uncontrollably presented on different levels.  It would be difficult even to thoroughly understand the activities of cell, the most fundamental unit of organism.  To investigate life on cellular level, both internal and external constitution must be clarified.  As pointed out by the scientists, the blueprint was in the forming molecules.  However, what if was the blueprint not only in the molecules, but also outside the molecules, or even in the interaction between molecules?  In this case, identification of life activities would not be simple and accomplished by the understanding only on the local features of organism.

According to life mechanisticism, life is as simple as a computer.  No matter how complicated are the circuits, integrated circuit could participate in the computer formation as an independent unit which can be changed with a new one and still work as usual.  Is this the case in the constitution of real life?  2000 years ago, Aristotle from ancient Greece used an oldest metaphor to describe the local and global relationship: hand was connected with arm.  When form as a united organism, hand functioned as hand.  When separated from arm and lost the unison with the organism, hand lost its function and was not hand any more, even it still kept the appearance.  This was the most original and plain organic theory.

As early as in 1930s, physiologist Holden criticized that the pure mechanistic explanation could not clarify the phenomenon of life unison.  Ritter invented the word ‘organicism’ to demonstrate the organic theory of life.  He described life as: the correlation between the entirety and the components, including the sequential regulation between components and their interdependence essential for the existence of the entirety, as well as the absolute control of the components by the entirety.  Novikoff showed in detail that why the explanation of organism must be integrative: “The whole on a certain level is the component of a higher level.  Both the parts and the wholes are substantial entities, and the integration caused by the interaction between components is resulted from the integrative feature of the components.  Because the vitalism excludes the reductionism, it opposed to describe the organism as a machine consisted of independent parts (physical and chemical units), which could be removed like taking a piston from the engine, and all parts could be described by their functions and natures without mentioning their origins.”  In contrast, due to the interaction between the components in biological system, the merely description of each component was unable to demonstrate the integrative nature of the system.  It was the tissue between the components actually controlled the entire system.

From cell to tissue, organ, organ system, and the entire organism, there is component integration on each level, which can be seen on biochemical level, genetic level, and individual level.  All organicists agree that no system can be clearly explained by the natures of each component.  Organicism is based on the fact that organism contains tissues.  Organism is not formed as a pile of stones by properties and molecules.  The function of organisms is determined by properties, intermolecular tissues, intermolecular correlation, molecular interaction, and molecular interdependence.

The advanced development in microcosmic study in life led people to thorough understanding and away from entirety at the same time.  It seemed difficult for people to globally or systematically view life.  Under this background, Rongxiang Xu’s in situ stem cell research led people back towards the history and the recognition of life with systemic organic point of view.

The correlation between stem cells and organic physiological environment established by Rongxiang Xu revealed that the significance of life was not only organic, but also dynamic.  In other words, on one hand, life is a united and integrative system in which each part is controlled by the organism to meet its global needs and can not independently exist.  Without the connection with the organism, each part would lose its specific function in specific organism and therefore, lose its meaning.  On the other hand, life is a dynamic system in which each part positions itself and performs its own tasks in the united environment and under the commend from the organism in order to support the whole organism.

Because its simplicity and primitiveness, the organic view establishes a straightforward and principled concept about life activities.  No matter how thorough and deep the microcosmic understanding about life is, even on the molecular level to study the basic unit of cell and its fertilization, differentiation, growth and proliferation, and signal transmission, it should not contradict with the fundamental characteristics of life, which are the organic nature of cell activities revealed, on the basis of realistic clinical achievements, by Rongxiang Xu’s stem cell research.

Based on the activation of somatic cells to become stem cells, and on the directed differentiation of in situ stem cells, let’s review the stem cell activities: when skin was injured, it was managed by Rongxiang Xu in whole body macrocosmic physiological environment, instead on microcosmic molecular level, which maximally and artificially built the physiological environment for the wound; under the condition by which the basic life activities were functionally maintained, the organism automatically sent signals through information exchange in order to repair the injured tissues; provided with bionic designed essential regenerative nutrients, somatic cells in the organism automatically initiated the procedures directed by the commend and transformed into primitive embryonic stem cells; the embryonic stem cells then started tissue regeneration by the organic differentiation procedures acquired during the zygote period.  However, during the process of tissue regeneration, embryonic stem cells did not passively produce the tissues as the origin.  They accurately determined the amount of repairing tissues by the severity of the injury, and therefore to produce optimal healing without excessive proliferation which might cause skin protrusion, or inadequate repair which might lead to sunken skin.  This is the true dynamic feature of stem cell life activities disclosed by Rongxiang Xu.

Facing the perfectly repaired muscle and skin, we have to wonder: in this world, what kind of stem cells can accomplish this marvelous masterpiece as in situ stem cells, and what kind of ability can exceed the great potential hidden in life itself.

Finally, we come back again to the old issue pursued by philosophers for thousands of years, which is the relationship between human and nature. In front of the objective world, how powerful is human dynamics?  Can human being change the natural progress of life on the most fundamental level and therefore to beat the nature?  If we can serve people by conforming to the nature, then what is the point to exhaustedly struggle with and finally to go beyond the nature?  Back to the reality, what we consider will be more practical.  If life tissues can restore the physiological environment for diseased organisms and provide the prerequisite activation conditions for stem cells with low costs, and therefore to achieve the regeneration and repair of organic tissues, then what is the practical value of the tissue engineering involving in vitro tissue culturing and organ transplantation by stem cell?

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