The Chinese Medical Canons’ View on Immune Response and Its Regulation
By Arnaud Versluys, PhD, MD (China), LAc
In biomedical terms, immunity is ‘a condition of being able to resist a particular disease especially through preventing development of a pathogenic microorganism or by counteracting the effects of its products.’ The actual process of resisting the pathogenic perpetrator is called immune response or immune reaction, which is ‘a bodily response to an antigen that occurs when lymphocytes identify the antigenic molecule as foreign and induce the formation of antibodies and lymphocytes capable of reacting with it and rendering it harmless.’
The concept of immunity is omnipresent in classical Chinese medical literature. And in particular, immune response is described as early as in the Han dynasty (circa 200 BC) Huangdi Neijing, or the Yellow Emperor’s Inner Canon, therefore being the first and foremost medical textbook to spell out in great detail the step by step process that the body goes through when responding against pathogenic affliction.
The Neijing Spiritual Pivot anecdotally describes the following: “Huangdi says: How is pain engendered? For what reason and what is it called? Qibo answers: Wind cold and damp qi, lodge between the flesh layers, and push and poke thus causing foam, whereupon the foam collects when encountering cold. The accumulation spreads the layers apart and causes them to rupture. The rupture causes pain, and the pain causes shen to arrive神歸, for when the shen arrives there is fever, and with the fever the cold resolves…”
Shen here refers to the organism’s immune awareness. This activity is governed by the heart as it represents the emperor. A good emperor becomes aware of a border breach as early as possible, and commands the triggering of defense mechanisms to rectify such breach. The imperial awareness arrives at the site of damage, and along with itself brings the fire of the South, which in the periphery is known as yang or protective.
The arrival of the imperial yang protective of the South at the location of breach is the classical view on immune response and clinically presents as fever. Ming dynasty Neijing commentator Zhang Jiebing explains: “With pain, the heart pours into the region, for this is the arrival of shen. The arrival of shen is the arrival of qi. The arrival of qi causes heat. And the heat causes the cold to disperse and the pain to briefly resolve.”
Neijing Suwen clearly establishes the link between external invasion and fever by saying: “All febrile diseases nowadays belong to the category of Cold Damage.” Biomedicine considers that “Fever is the body's reaction to pathogens; it attempts to raise core body temperature to levels that will speed up the actions of the immune system, and may also directly denature, debilitate, or kill the pathogen.”
Cold Damage is the Han dynasty name of what we now commonly refer to as ‘external invasion’. The Nanjing or Classic of Difficulties states: “How many types of Cold Damage are there? … There are five types of Cold Damage, these are Wind Strike, Cold Damage, Damp Warmth, Heat Disease and Warm Disease, and their [inflicted] suffering is all different.” As such it is clear that what the classics consider fever is the body’s attempt at optimizing body temperature, to provide optimal conditions for the functioning of the immune system and its response against illness of any possible nature, be it cold, damp, warm, hot, etc.
The above is the Han dynasty equivalent of modern medicine’s view of the mechanism and function of fever: “In many respects, the hypothalamus works like a thermostat. When the set point is raised, the body increases its temperature through both active generation of heat and retaining heat. Vasoconstriction both reduces heat loss through the skin and causes the person to feel cold. If these measures are insufficient to make the blood temperature in the brain match the new setting in the hypothalamus, then shivering begins in order to use muscle movements to produce more heat. When the fever stops, and the hypothalamic setting is set lower; the reverse of these processes (vasodilatation, end of shivering and non-shivering heat production) and sweating are used to cool the body to the new, lower setting.” As such it becomes clear that fever is the response that the organism triggers in order to optimize immunity by regulating the body temperature to stop the progression of an acquired illness and rectify physiology.
The above phenomenon of raising peripheral body temperature through vasoconstriction is in the Shanghan Lun or Treatise on Cold Damage referred to as Taiyang disease, as it manifests with aversion to cold and body aches. More specifically, the process of vasoconstriction will lead to the absence of sweating and aversion to cold which in Shanghan Lun terms is called Taiyang Cold Damage. This is why in such instances, the pulse becomes very tight. While fever to regulate body temperature through vasodilatation will produce a sweat along with the fever and is in Shanghan Lun terms referred to as Wind Strike which is accompanied by a milder form of cold aversion, known as wind or draught aversion. The latter cannot present with shivering, and is imperatively accompanied by sweating. The opening of the vessels makes the pulse feel soft or moderate.
The intention of treatment will be to assist the body in this febrile process to adequately regulate peripheral immune function through thermo-regulation and counter the breach, thus effectively undoing the disease process. The herbal medicine practice recorded by Han dynasty Zhang Zhongjing in his Treatise on Cold Damage or Shanghan Lun is the premier instruction on assisting the body in this process using canonical herbal formulas. The canonical prescriptions are the magistral formulas of our medicine. The differentiation system used by Zhang Zhongjing is based on a model of six conformations. This system differentiates six types of yang functional expressions. From the perspective of thermodynamics, the yang conformations govern peripheral temperature regulation, while the yin conformations govern visceral temperature regulation.
Taiyang is the first stage and its function is to help the body maintain steady peripheral blood temperature through vasoconstriction or vasodilatation. Damage to taiyang results in the inability to stabilize one’s body temperature resulting in upward or downward deregulation and fever. Its hallmark febrile symptom is fever with aversion to cold or wind.
The second stage is yangming and its function is to prevent the body from over-heating and dehydrating through the abundant generation of cool moisture in the lung and skins. Damage to yangming results in the heating up of the air in lungs and stomach and consequent drying up of cooling moisture, resulting in the inability to stop the proliferation of fever and sweating. The hallmark clinical presentation is high fever with aversion to heat.
The third stage of the thermo-regulatory chain is called shaoyang. Shaoyang governs the transfer from peripheral body temperature into the viscera through the internalizing of warm gasses or qi embedded in nutritive humors. Damage to the physiology of the shaoyang conformation results in a generally lower fever than the previous stage, but alternated by chills. The treatment of these three stages is then the re-regulation of their thermodynamics. The methods are recorded in great detail in the Shanghan Lun and suggest the use of well-known formulas such as Mahuang Tang, Guizhi Tang, Baihu Tang, Tiaowei Chengqi Tang, Huangqin Tang and Xiao Chaihu Tang, among others.
Failure to assist the body in duly performing the aforementioned three functions will lead to annihilation of peripheral body defenses and the inward progression of the pathological damage to the body. This is called the passage of disease from yang conformations into yin conformations. The yin conformations are the functions of the solid organs which will deregulate as their yang gets damaged. Damage to the yang of the viscera equals deregulation of the temperature of said organs. Once disease is allowed to penetrate to the depth of the yin conformations, the initial functional impairment of the yang conformation disease will give way to physical and material damage to viscera and their corresponding tissues. Treatment of the three yin stages is also recorded in the Shanghan Lun in great detail and uses cardinal prescriptions such as Sini Tang, Zhenwu Tang and Danggui Sini Tang, to name but a few.
As such it should become clear that the Han dynasty model of the six conformations is a metaphor to describe the body’s intricate ways of maintaining healthy body temperature and consequent immunity against external pathogenic influences. There is no contradiction with current biomedical understanding of the immune system. And it is the best way to understand how to assist the body in re-establishing homeostasis and consequent health. Through study of the Neijing theories on the subject matter, one can gain understanding of the functions of the six conformations, while the Shanghan Lun provides us with instructions on how to clinically recognize the symptoms associated with failure of the different stages as well as provides us the herbal prescriptions necessary to cure the dysfunction of the conformations, thus constituting the most original and coherent medical system to regulate a human organism’s immunity and balance with its environment.
About the Author:
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