Dorothy FarrarImmune system (immunization, immunity)
The immune system ( immunity ) includes the entirety of all defense reactions of a body against occurring pathogens with which it is confronted, such as bacteria, fungi, viruses even against other foreign proteins (e.g. toxins). Immunity is the insensitivity to pathogens of infectious diseases (contagious diseases). A distinction is made between natural and artificial immunity.
What is the immune system?
Contagious diseases (infectious diseases) are mainly caused by bacteria , viruses , unicellular fungi or animals. But their toxic excretion products can also be the cause.
Not every infection inevitably leads to a disease. This depends on the extent to which the body or our immune system is able to form certain defense substances (antibodies) quickly enough and in the appropriate amounts. It is very likely that the overall physical condition also plays a role.
Antibodies are the body’s own defenses (antigens). These are special proteins that are dissolved in the blood plasma or bound to the surface of special white blood cells (lymphocytes). These are able to render foreign substances (antigens) that have penetrated harmless.
Humans naturally have an innate immune system (immunity) against many bacteria and viruses, which is caused by certain defense mechanisms. The skin prevents the penetration of pathogens or their excretions into the body with its protective acid mantle. Pathogens that have already penetrated are destroyed by specific white blood cells (scavenger cells) or killed by their cell products (eg interferons).
In the course of life, immunity against very specific pathogens can be acquired through the formation of antibodies. A prerequisite for the natural immune system is that the person has already experienced and overcome the infectious disease.
Artificially acquired immunity can sometimes lead to a mild course of the disease. Vaccination is carried out with weakened or killed pathogens. The immune system is stimulated to form antibodies against the cause of the disease itself. Both natural and artificial immunity require the presence of antibodies in the blood against certain pathogens.
What is immunization (immunity)?
Immunization is the achievement of immunity to infectious pathogens. There are two different types of immunization, active and passive.
Natural immunity can be innate, such as in humans against various animal diseases (foot-and-mouth disease) or acquired by surviving an infectious disease (eg, diphtheria).
Artificial immunity is achieved through vaccination (immunization). These are exogenous macromolecules of a living nature (e.g. bacteria, mould) or inanimate nature (e.g. foodstuffs and medicines) which, once they have penetrated the body, can trigger a specific immunological defense reaction.
In active immunization, weakened or killed pathogens are vaccinated. In this case, the body produces its own defenses (antibodies). This type of immunization is used for the following infectious diseases: eg to protect against polio, diphtheria , tuberculosis , measles , smallpox and whooping cough . However , for some diseases, such as diphtheria and tetanus , multiple vaccinations are necessary to achieve lasting protection.
In passive immunization, a serum containing antibodies is injected. This type is used when an infection is already present and the body’s defenses are weakened and require support. Although this vaccination works immediately, it does not last long because the injected antibodies are quickly broken down by the body.
History of immunization (vaccination)
How did vaccination come about? Who was the founder? In 1796, the English doctor Edward Jenner made a discovery that led to a medical advance in the successful fight against infectious diseases.
During a smallpox epidemic, Jenner observed that people (mostly milkers) suffering from harmless cowpox were not seriously affected by the disease. They were protected from that dangerous human pox. At that time, however, many people died from this very contagious, serious infectious disease.
Jenner looked for crucial connections between these different types of smallpox and dared a risky experiment. He injected small cuts in the skin of children with liquid from the pustules of smallpox cattle and was successful. None of those vaccinated contracted smallpox. In this experiment, the children were artificially confronted with harmless cowpox.
These did not cause disease, but there was an immune reaction. Your body formed specific antibodies that also provided adequate protection against the pathogen that causes the dangerous human smallpox. Formed memory cells provided immediate protection in the event of a new infection caused by the same or similarly structured pathogens. After vaccination against human smallpox was introduced, the death rate dropped significantly.
Active immunization (vaccination)
We humans can protect ourselves from many infectious diseases through vaccinations, which often led to death in the Middle Ages. With active immunization ( vaccination ), killed or weakened pathogens are often also vaccinated with their excretion products. Certain white blood cells (lymphocytes) then form antibodies that react with the pathogens (antigens) and thus render them harmless.
The body produces its own antibodies, it has to deal with the pathogens itself. Antibodies bind several antigens and clump them together, an antigen-antibody reaction takes place. Scavenger cells (white blood cells) then destroy these clumps. Most pathogens are successfully combated in this way.
These endogenous antibodies can exist for many years or even be formed again and again throughout life if necessary. For this purpose, special lymphocytes, which do not participate in the antibody reaction, convert into so-called memory cells after an infection. These cells are very durable. If there is another infection with the same pathogens, they immediately ensure the formation of pathogen-specific antibodies. The organism has become immune to one type of pathogen and that is exactly why we usually get childhood diseases only once.
A prerequisite for the use of this type of immunization is that there is no infection at the time of vaccination or that there was no infection for some time. The doctor must clarify this in advance so that the organism is not additionally stressed and weakened. This artificially acquired immunity can sometimes lead to a mild course of the disease. This method does not work immediately, but its effect sometimes lasts for a very long time. In any case, it should be seen as a preventive protective measure against infectious diseases.
Passive immunization
In this immunization, a healing serum that already contains specific antibodies is injected. These immediately begin to fight the pathogens. The serum is used to heal infectious diseases that have already broken out and is therefore used in the body of sick people.
The already weakened body is supported in its fight against the pathogens by the supplied ready-made antibodies. This lasts until it is able to produce enough antibodies on its own. Although this vaccination works immediately, it does not last long, since the foreign serum proteins are quickly broken down again by the body’s own immune system.
To produce the vaccine, animals are repeatedly vaccinated with weakened or killed pathogens. Their immune system then reacts by forming specific antibodies, which are later filtered out of the blood plasma.
The liquid blood serum is processed together with the antibodies into the vaccine. It has to be used after about 2 to 3 weeks, since the antibodies break down after this time. Nowadays, such antibodies are increasingly being obtained from human blood, which offers the appropriate conditions.
Bacteria are also used to produce antibodies. For this purpose, the genetic material of a bacterium is changed and thus manipulated.
By inserting the corresponding human genes into the genome of the bacterial cell, its entire metabolic apparatus is adjusted to the synthesis of human protein . Bacteria thus acquire the ability to produce special antibodies whose proteins are identical to those in human blood.
The industrial mass production of these artificially generated bacterial mutants with the desired properties is economically feasible thanks to complex biotechnological processes. Antibodies produced using this method are very popular in medicine because they are simply better tolerated by those affected.
Hello and welcome to my Health Guide & Encyclopedia! My name is Dorothy Farrar, and I'm the founder and main author of this platform.
My passion for health and wellness started at a young age when I became interested in the connection between the food we eat and the way we feel. This fascination led me to study nutrition and dietetics in college, where I learned about the importance of a balanced diet and the impact of various nutrients on the body.