What is your Immune System?
Our immune system makes sure that no harmful microorganisms or particles enter and hurt the body. The system is a complex cooperation between cells, organs, and different types of proteins. The immune system is often divided into two; the innate immune system and the acquired immune system.
The innate immune system
The innate immune system is the inherited defense, which is the part of the body from birth. This part of the immune system reacts as soon as it detects anything, which is not a part of the body itself. It does not distinguish between the different degrees of threats, but strikes with equal force every time. For this reason it is also known as the unspecific immune system. It reacts relatively slowly, and time is valuable, if the body is attacked by e.g. pathogenic (disease causing, harmful) bacteria, which multiplies rapidly.
The different parts of the innate immune system are:
• Macrophages: Are found in the tissue. When they encounter intruding bacteria, they initiate an infection response, like blushing, heat and swelling (in an isolated area).
• Natural killer cells: Recognize cells, which contain virus and kill them.
• Neutrophil granulocytes: Live for a short period of time and eat the intruding microorganisms, which create pus.
• Dendritic cell: Acts as a sort of gatekeepers, which capture the intruding microorganisms and transport them to the nearest lymph node, where the acquired immune system is located.
• Acute phase-proteins: A group of different proteins, which support the other processes e.g. by attaching to the surface of the pathogenic cells and “brand” or harm them.
The acquired immune system
Opposite the innate immune system, the acquired immune system is under constant development.Every time we face a new microorganism, the body notes whether the microorganism is pathogenic or not, so the body can produce the antibodies, which are necessary for eradicating it. If the body has been in contact with a pathogenic microorganism once, it will have tailor-made “ammunition” ready, should it return. Therefore this part of the immune system is quick to respond to incoming threats.
The acquired immune system consists of:
• T-cells: Localize and attack intruding cells
• B-cells: Produce antibodies
The role of the micro-flora and probiotic bacteria in the immune system
The beneficial microorganisms in the intestine work to protect the body. Many of them produce substances, which are toxic to pathogenic bacteria, and generally beneficial intestinal bacteria produce lactic and acetic acid, which make the environment in the intestine inhabitable to pathogenic bacteria. Another important quality of the micro-flora is its ability to compete with pathogenic bacteria for adhesion locations on the intestinal mucosa and for nutrients. In this way the micro-flora contributes significantly to inhibiting the proliferation of intruding microorganisms.
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