The immune system is the body’s defence mechanism against pathogens. This system comprises of many cells that work together to protect the body from foreign invaders such as bacteria, viruses, parasites as well as tumours. The immune system is divided into two primitive forms, the innate and adaptive systems. The roles for both types are vital in the immune system; the innate is the rapid, non-specific primary response against any foreign material the body encounters, whereas the adaptive system is a secondary response and a more specific line of defence. The adaptive as well as the innate responses initiation are hugely associated with each other. The innate response consists of many components; these include mechanical, chemical, humoral as well as cellular barriers. The main line of defence in the innate system is the cellular component; there are different types of cells involved, however, the most critical cell of all other different immune cells is called a macrophage. Macrophages are a phagocytic cells originated from monocytes, a form of blood leukocytes. Monocytes are made by bone marrow in the myeloid lineage through committed haematopoietic stem cells in a process called haematopoiesis. Macrophages carry out indispensable roles in the immune system; they are involved in both of innate and adaptive responses. Thus, macrophages are always referred as the cells that ‘bridge’ the innate and adaptive systems. This essay will discuss the functions and activities of the macrophage that make it the most important cell in the immune system. Monocytes are the precursors for macrophages; these monocytes migrate and differentiate into tissue macrophages once they encounter an infection. Macrophages are distributed around the w... ... middle of paper ... ...al, anti-parasitic as well as anti-tumor activities. Macrophages play an important role in the defence against tumours. This defence is achieved by the rapid response, the production and secretion of various cytokines that target the activation of dendretic cells (DC) and natural killer cells (NK). INF-y is the main cytokine that drive NK to stop the progression of tumour, and NK cells to activate the T cells to respond to the danger (Lamagna et al. 2006). Tissue repair is critical for the body in order to regenerate the destruction of tissue during the inflammatory response. Macrophages are crucial for the resolution of the tissue. This is done by the secretion of the cytokine GM-CSF which is a colony stimulating factor; it proliferates and results in tissue healing. Also, macrophages secrete collagenase and elastase enzymes that promote tissue repair.
The immune system is made up of a network of cells, tissues, and organs that work together to protect the body, and it defends the body from “foreign invaders.” Immunity can be divided in two three different defenses, and these are defined as first, second and third lines of defense. The first line of defense for the immune system is the primary defense against pathogens entering the body from the surface in order to prevent the start of disease and infection. Some examples of the first line of defense is the skin, protecting the external boundaries of the body, and the mucous membranes, protecting the internal boundaries of the body. Although the skin and mucous membranes work on the internal and external boundaries, they both release chemicals
Repair after a muscle is damaged happens through the division of certain cells who then fuse to existing, undamaged muscle fibers to correct the damage. Different muscle types take different amounts of time to heal and regenerate after it has been damaged. Smooth muscle cells can regenerate with the greatest capacity due to their ability to divide and create many more cells to help out. While cardiac muscle cells hardly regenerate at all due to the lack of specialized cells that aid in repair and regeneration. In skeletal muscle, satellite cells aid in helping restoration after injury. Along with muscles, tendons are very important structures within the human body, and they to can be damaged. However, tendon repair involves fibroblast cells cross-linking collagen fibers that aid in not only reinforcing structural support, but also mechanical support as well (“Understanding Tendon Injury,” 2005). While quite different from muscle repair, tendon repair involves the similarity of reestablishing d...
“Cells Involved In Immune Responses and Antigen Recognition.” Microbiology and Immunology. Web. 18 Dec. 2011. .
Mycobacterium tuberculosis (MT) is a slender, rod-shaped, aerobic bacillus which causes tuberculosis. Tuberculosis (TB) is an airborn infection which is transmitted via inhaling droplet nuclei circulating in the air. These droplets are expelled from the respiratory secretion of people who have active TB through coughing, sneezing, and talking (Porth, 2011). Some bacilli stay in the upper airway and are swept out by mucus-secreting goblet cells and cilia on the surface of the airway. Others will escape from this protective mechanism to travel and settle down at alveoli (Porth, 2011). Local inflammatory reaction occurs and macrophages are cells that act as next line defense mechanism to fight with mycobacteria. First they engulf micobacteria, try to reduce their strength and ability, and kill them. In the same way they send antigen to helper T lymphocytes to initiate a cell-mediated immune response (Knechel, 2009). The infected macrophages will send produced cytokines and enzymes to breakdown mycobacteria’s protein. It is the released cytokines that attract T ly...
.... Glioma-initiating cells: a predominant role in microglia/macrophages tropism to glioma. Journal of neuroimmunology 232, 75-82.
2. Cytokines in Cancer Therapy. Francis R. Balkwill. Oxford University Press, NY, 1989. pp 1-8.
The structure and function of our immune systems is a great help for our body to keep all of us healthy. Our immune system has a specific structure that it should maintain. There are also organs that play a major part for the health of our immune system. These organs are called lymphoid organs because of the lymphocytes that inhabit that area. (white blood cells) Bone marrow is also one of the key elements for the immune system, this is where all of our blood cells are being made along with the white blood cells. With the help of the bone marrow, white blood cells are constantly traveling throughout our bodies using the blood cells for help. Another structure that is important for our immune system is lymphoid tissue. Lymphoid tissue acts as a gateway into our bodies that help to prevent incoming germs.
Our immune system protects our bodies from pathogens like bacteria and viruses very efficiently in most cases. One big question that has come up is why does the immune system not respond to cancerous cells in the same way? Why are cancer cells not eradicated like other dangerous foreign cells? This seems very strange, especially since the immune system has cells that are specific to destroying cancer cells and virus-infected cells, called natural killer cells. To begin to answer this question it is useful to examine cancer cells and their interactions with the immune system in more detail.
The immune system has the important job of protecting the body from foreign invaders. It is made up of a network of cells (including white blood cells), tissue and organs. The foreign invaders the immune system fight include viruses, bacteria, microbes and pathogens. In order to stop these foreign invaders, there is a process known as immune response that attacks in three different lines of defence. Without this immune response, the body would be constantly under invasion by pathogens trying to attack and induce illness.
When a cell in our body has become infected or has become cancerous it’s surface changes. This is how the immune system can tell good cells from bad ones (the markings on the surface.) Once a bad cell has been recognized our bodies sends cells to destroy the damaged cell and prevent the spread of whatever caused the damage in the first place. The next step our body takes is to have the affected cells start to produce interferons and other helpful substances. These help to fight off unwanted organisms, and also to warn other cells of the invaders and prepare them to resist them therefore preventing the spread of disease.
There are three different types of granular leukocytes. Neutrophil is a phagocyte, produced in the bone marrow that ingests and destroys bacteria extremely fast. Neutrophil has a diameter, which is, about ten to twelve micrometers long. They make up about 60-70 percent of the total number of white blood cells in our body. Eosinphil is a type of white blood cell that secretes poisonous materials in order to kill parasites, allergies and phagocytosis of bacteria, which is when the...
Adaptive immune system happens much quicker to the presence of an “infection creating potent mechanisms for neutralizing or eliminating the microbes. There are two types of adaptive immune responses: humeral immunity, mediated by antibodies produced by B lymphocytes, and cell-mediated immunity, mediated by T lymphocytes.”
We are always hearing on the news and in newspapers about children catching diseases and often dying from them. Why is this happening when all of these diseases are easily preventable by simply being immunised, why aren’t parents getting their children Immunised, is it for religious beliefs or just carelessness. What ever their reason may be is it really good enough, because why would anyone rather let their child be able to catch and spread a deadly disease then have them Immunised, so Immunisation should be made compulsory for all children.
In its nature, collagen is like the backbone of the skin and is responsible for its elasticity and structure. It’s also responsible for replacement of dead skin cells with new ones giving the skin a radiant
The human body is very complex. It is like a job. You have to do a million things in one day to make it through the day. The body uses nine systems to do all of those jobs. They all have separate functions, but some work together. Each system is also made up of organs. There are many ways to care and protect the systems from the many different problems they can have. There are also many interesting facts about each system.