What is IgY?
IgY is the English abbreviation of egg yolk immunoglobulin. It is a specific immunoglobulin that uses specific antigens to immunize laying hens multiple times, inducing laying hens to differentiate into plasma cells, secrete specific IgY into the blood, and transfer into the yolk when the blood flows through the ovaries.
Mammals have 5 types of immunoglobulins: IgA, IgM, IgG, IgD and IgE, the most important of which is IgG. IgG plays a major protective role in body immunity and achieves antibacterial and antiviral purposes.
There are three types of immunoglobulins in the serum of birds: IgA, IgM and IgY. The main ones are IgA and IgM in the egg white. Because the IgY molecule is small, it can specifically bind to the yolk membrane to enter the yolk, and the main ones are IgY in the yolk. The structure of
IgY
IgY and IgG are both immunoglobulins, with similar basic structures, and are composed of two heavy chains and two light chains.
IgY heavy chain consists of 1 variable region and 4 constant regions, while the IgG heavy chain consists of 1 variable region and 3 constant regions; IgG has a hinge region, while IgY has no hinge structure, and the structure is more stable.
IgY molecular weight is 180 kDaltons, while IgG molecular weight is 150 kDaltons.
IgY is more hydrophobic than IgG.
IgY isoelectric point is between pH value 5.7~7.6, while IgG isoelectric point is between 6.1~8.5. Physical and chemical characteristics of
IgY
IgY has good stability and has heat resistance, acid resistance, alkali resistance, ion resistance and certain anti-enzyme degradation capabilities.
Thermal stability: IgY has good thermal stability under conditions below 75℃, and its activity still has no significant change in storage at 4℃ for 5 years or at room temperature for 18 months; the pasteurization activity will not decrease under 30 minutes at 60℃, and the activity will not decrease in 85℃ for 5 minutes.
acid and alkali resistance: IgY has a wide tolerance range to pH, which is relatively stable at pH 3.5~11.0. Activity begins to decline at pH 3.0 and above pH 12.0.
Anti-enzyme degradation: IgY has a high resistance to pepsin, but is very sensitive to trypsin, can resist the digestion of pepsin and eliminate the gastric acid barrier. The immune function of
IgY
The immune function of IgY contained in poultry eggs is basically equivalent to the IgG contained in mammals and colostrum.
IgY naturally produced by avians is the same as the maternal antibody contained in mammalian colostrum. It is essentially the maternal antibody of avians, which can cause the embryos and young chicks to have passive immune effects, thereby protecting the embryos and young chicks.
IgY prepared by humans has been widely used in disease prevention, diagnosis, treatment and health care in humans and mammals. If the antigens used in preparing IgY are different, the pathogens that can be prevented and treated by the produced IgY are different: for example, IgY produced with canine parvovirus antigen can prevent and treat canine parvovirus; IgY produced with swine epidemic diarrhea virus antigen can prevent and treat swine epidemic diarrhea; IgY produced with pig E. coli antigen can prevent and treat piglet yellow and white dysentery. Anti-pathologic mechanism of
IgY
IgY anti-pathologic mechanism belongs to passive immunity. There are two ways of immunization in animals: active immunity and passive immunity. Natural infection or vaccination stimulates the body's immune system, and the body's own production of immunoglobulins is an active immunity. Female animals are transmitted to fetus and young animals through placenta or colostrum, and female poultry is transmitted to maternal antibodies of embryonic eggs and young chicks through yolks. They are passive immunity for fetus and young animals, embryonic eggs and young chicks. Injection or feeding immunoglobulin to animals to directly eliminate pathogenic factors in the body is a passive immune disease prevention and treatment method. There are three mechanisms for IgY to prevent and treat diseases.
anti-specific pathogens: IgY directly adheres to the cell wall, pili or flagella of the pathogen, inhibits the pathogen from playing a role on the intestinal wall, and causes the parenteral bacteria to lose the ability to adhere to host cells, destroy the integrity of the pathogen and inhibit its proliferation; some IgY degrades the action of intestinal digestive enzymes into binding fragments (Fab fragments), where the fragments containing antibodies can become small peptides that are easily absorbed by the intestinal mucosa, and bind to specific pathogenic factors after entering the blood, while the stable part (Fc fragment) remains in the intestinal but will lose its pathogenicity to susceptible cells.
Anti-specific virus: IgY affects the fusion of the virus membrane and the cell surface by binding to the surface receptor of the virus particle or adhering to the virus capsid, and inhibits the growth and reproduction of the virus.
neutralizes toxins and anti-tumors, etc.: IgY can neutralize the toxicity of toxins produced by bacteria, molds, etc., inhibit the secretion of tumor necrosis factors by macrophages, reduce inflammatory responses, and inhibit the binding of endotoxins to target cells, avoid adverse subsequent reactions and secondary infections. Advantages of
IgY
There are two main ways to manually obtain immunoglobulins: one is to extract immunoglobulins from the blood to make various high-immune serums that can be injected; the other is to extract from yolk to make various oral immunoglobulins.
Traditional anti-disease serum products need to use blood as raw material. The disadvantage of this method is that the source of raw materials is limited, the preparation cost is high, and the more important hidden danger is that it is prone to cross-infection. Extracting IgY oral immunoglobulin from yolk successfully overcomes this problem. Its disease prevention function is the same and even has greater advantages.
is easy to obtain: no blood collection is required, just collect the eggs laid by immunizing the poultry to obtain antibodies. Using a small amount of antigen to immunize the poultry can not only obtain a large amount of specific IgY with uniform quality, but also have high yields of specific antibodies, relatively low cost, and are beneficial to animal welfare protection.
safe to use: Due to the large difference in the germline occurrence distance, there will be no cross-serological reaction between avian IgY and mammalian immunoglobulin, it will not activate the mammalian complement system, do not bind to rheumatoid factors or Fc receptors, it will not interfere with immune detection results, will not cause cross-infection, and it will be safer and hygienic than antibodies extracted from mammals.
has better effect: IgY has a high response to mammalian antigens. Due to its low cost, it can be used in larger doses than serum antibodies. It can directly exert immune effects in the digestive tract for digestive tract infection, and the effect is better. Compared with active immunization by injecting vaccines, vaccines can only be prevented, and the proportion of immunization failure is large. IgY can not only prevent it, but also can be used for treatment after animal infection and conditioning after recovery. No drug resistance, no residue, no pollution, safe and efficient.
is easy to store and transport: Due to the good stability of IgY, the activity can be stored for 5 years at 4°C for 5 years. The activity is almost unaffected under room temperature for more than 18 months. Therefore, cold chain and other storage measures are unnecessary. Not only can it be used as auxiliary treatment drugs for animal hospitals and feed factories as functional additives, but it is also very convenient for small and medium-sized breeders or pet owners to purchase and use them on their own. Application of
IgY technology
IgY technology, that is, a series of technologies for the research, development, production and application of IgY antibodies. The research and development of a new specific IgY antibody is a relatively complex process that requires the cooperation of many biologists, pharmacists or veterinarians, and many results have been achieved in the past decade. The production and preparation process of IgY products is complex and has strict requirements. The process flow includes: immunogen preparation → immunization → pollution-free feeding throughout the process → high-egg free → egg separation and extraction → pasteurization → low-temperature spray drying → detection → sterile packaging.
IgY products have been widely used in the diagnosis, prevention, treatment and health care of human and animal diseases.
Diagnosis: IgY monoclonal antibodies have been used to establish diagnostic methods for certain bacteria, viruses, parasites, tumors and other diseases, with high detection sensitivity and strong reliability.
Prevention and treatment: The most important application of IgY is currently the prevention and treatment of intestinal diseases in humans and various animals. For example: used to prevent human Helicobacter pylori disease; used to prevent and control diseases such as E. coli, Clostridium veterinary artery, infectious gastroenteritis, rotavirus and swine epidemic diarrhea that causes diarrhea in piglets; it can also be used to prevent pet diseases such as parvovirus disease in dogs and cats, coronavirus, and rotavirus.
Animal Health: The most promising application of IgY is the development of anti-free feed additives that replace antibiotics. With the increasing prominence of drug residues and microbial resistance in livestock and poultry products caused by the abuse of antibiotics, the country has issued laws and regulations to ban anti-antibody in 2020. As a biologically active immunoglobulin, IgY has unique advantages as a replacement product for antibiotics with its unique physical and chemical properties and biological functions. IgY not only promotes the growth of pigs, broilers, etc., but also has no drug residues and drug resistance problems. It is a green and environmentally friendly feed additive with development prospects.
Yu Chongkang
It needs to be emphasized in particular that IgY is highly specific, and each IgY is only for a specific pathogen. However, in actual clinical practice, dogs and cats are often infected with multiple pathogens or viruses as secondary bacterial infections after the primary disease. As a good product, this must be taken into account in research and development and design. produced by Beijing Huitong is compounded with various IgYs such as canine and cat parvovirus, rotavirus, coronavirus and E. coli, and also contains probiotics that regulate the intestinal microecology, Bacillus coli and prebiotics, which are conducive to the repair of normal intestinal microecology after the disease, allowing Aitong to restore her former health and cuteness as soon as possible; adding dog and cat intestinal repair factor (EGF) is conducive to the repair of intestinal chorionic; in addition, the high nutritional components contained in egg yolk are highly efficiently retained in Yutongkang, with 18 amino acids, 9 organic mineral trace elements, 13 vitamins, and especially added taurine acid, with the lecithin content not less than 100mg/g. It can be used for diarrhea rehabilitation, postpartum rehabilitation, postoperative rehabilitation, resistance to stress, oral antibodies during the immune gap, regulating the gastrointestinal intestines, and improving specific immunity, and is widely used.
hesheng—Yu Chongkang
