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
The job of the immune system is to keep “foreign” invaders out of the body, or if one gets in, to seek it out and kill it. These foreign invaders are called pathogens, which are tiny organisms that can cause an infection in the body. Pathogens can be bacteria, parasites, and fungi (http://www.niaid.nih.gov/topics/immuneSystem/pages/whatisimmunesystem.aspx).
Emerging evidence implicates microglial play critical roles to the CNS development of the brain. Microglial are unique population arise from immature yolk-sac macrophages that migrate and colonize the developing brain (Ginhoux et al., 2010; Ransohoff and Cardona, 2010). Interestingly, microglial (or their precursor cells) are selectively integrating into proliferative neurogenic zone of the proliferation and regulating the size of neural precursor cell pool via phagocytose neural precursor cell upon completion of neurogenesis(Cunningham et al., 2013). Also, colonization of microglia in the developing brain almost concurs temporally with brain vascularisation, neuroepithelial-radial glia transformation, neuronal migration, and myelination. Recent advent of transgenic technology and pharmacology allowed the role of microglia during development and their correlation with neural development disorder to be investigated extensively. For instance, pharmacologically knockout or inactivation of embryonic microglia resulted in increases of neural precursor cells pool (Cunningham et al., 2013). Similar phenomenons were also observed in genetically knockout of microglial in mice. Colony stimulating factor 1R-deficient (Csf1r−/−) mice w...
B-cells make antibodies that attack antigens, T cells make cytokines and attack damaged or diseased cells, and natural killer (NK) cells detect and destroy damaged cells. Cytokines are used in immunotherapy to cause cancer cells to die or to stop creating new cells. Cytokine-induced killer (CIK) cells are a group of natural killer (NK) T-cells that come from a blood cell having a round nucleus; peripheral blood mononuclear cells (PBMC). These blood cells are an important element in the immune system to fight infection and adapt to intruders. PBMCs can be extracted and cultured in vitro from patients with cancer. Immune cells identify major histocompatibility complex (MHC) present on infected cell surfaces, generating cytokine release and eventually causing apoptosis. However, CIK cells have the ability to detect infected or malignant cells in the absence of antibodies and MHC, allowing for a quick immune reaction. This characteristic of CIK cells can be useful as therapy for cancer and viral
cells into the wound. During the first few days after the injury, the body tries to
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.
Cell cycle is a complex mechanism that governs the cell growth and proliferation. Cell proliferation contributes to the continuity of life by producing cells, replenishing cells which undergone to cellular differentiation to acquired specialized phenotypes (function and morphology) to carry out living mechanism and towards the end-point-cell-death. Cell proliferation is determined by both extracellular signals such as cytokines and mitogen, and intrinsic cellular factors. Interactions of extracellular signals with intrinsic cellular factors trigger the biochemical events of cell proliferation. In the case of acquired immunity, proliferation is the important state after lymphocytes encountered to antigen presentation, and then leads to their effectors functions. Cell cycle regulators control the appropriate entry and progression throughout the cell cycle event. Thus, any cell cycle deregulation will potentially lead to tumourigenesis. (Malumbres and Carnero 2003)
The innate immune system is given to you at birth and always has microbes ready to fight (Joanne M. Willey, 2014). This system is very fast to detect and attempt to eliminate any invading cells. It reacts by triggering Toll-like receptors (TLRs) who then fasten to pathogen-associated molecular patterns (PAMPs) (Joanne M. Willey, 2014). The first line of defense in the innate immune system contains the skin and mucous membranes, along with normal microbiota (Joanne M. Willey, 2014). The second line of defense of the “early-warning” system consists of natural killer cells, phagocytes, eosinophils, dendritic cells, macrophages, inflammation, fever, and antimicrobial substances (Joanne M. Willey, 2014). Although a powerful system, it cannot take
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.
We are amazing human beings. Our bodies have been carefully constructed to protect ourselves from injury and harm. The protection of our body begins with the brilliant intervention of one small cell. According to Huether and McCance (2012), adaptive immunity is considered the third line of defense within our bodies. Adaptive immunity is summoned after the frontline or “external barriers” are compromised (Huether & McCance, 2012, p. 142). The process of inflammation arrives at the scene of invasion; next adaptive immunity is organized. Adaptive responses help our bodies fight disease at the scene. Additionally, adaptive responses maintain a unique memory to protect the body from future invasions. This paper will explore examples of the specific pathophysiology and associated alterations caused by adaptive responses.
The immune system is a highly evolved and complex defence system, armed against millions of potential pathogens that may cause infection at any point. Pattern recognition receptors, known as PRRs, are displayed by the cells of the innate immune system, such as macrophages and dendritic cells, and recognise pathogen associated molecular patterns or PAMPs. PAMPs are evolutionary conserved structural similarities found in many pathogens but not in the host’s own cells allowing the innate immune system to distinguish between self and non self and to react to the pathogens immediately (Mogensen, 2009). Antigen recognition receptors are used by the lymphocytes of the adaptive immune system to provide a highly specific and targeted response to a precise epitope of an antigen. However as a single lymphocyte carries only a single type of antigen recognition receptor that recognises one type of antigen the chance of a pathogen of finding a lymphocyte with a given specificity is low. Therefore the adaptive immune response takes time to mobilise hence the innate immune system is essential to keep the infection
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.
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.
Innate system critical main defense is the cellular component; there are several kinds of cells involved in the process. One of the crucial cells is the macrophage. ...
In addition to serving as a drainage system, the lymphatic system, along with the lymphoid tissues and organs, play a vital role in the body’s immune system to create an immune response. The body ...