what are Pathogens Antigens and Antibodies | Basic Concepts | Biology | Psychology

 

Basic Concepts of Pathogens Antigens and Antibodies

Ø Pathogens:

A pathogen is a disease-causing organism. Your body is naturally full of germs.

However, these germs can only cause problems if your immune system is weak or if they are

able to enter the normal sterile part of your body. Bacteria are different and can cause infections

when they enter the body. There are different types of bacteria, but we will focus on four of the

Most common types: Viruses, bacteria, fungi, and parasites.

Ø  Viruses:

Viruses are made up of a piece of genetic code, such as DNA or RNA, and are protected by a protein blanket. Once infected, the germs attack the host cells in your body. Then they use parts of the cell that hold them back, producing more viruses.

Ø Bacteria:

Bacteria are tiny organisms made from a single cell. They are very diverse, have a

variety of shapes and characteristics, and have the ability to live in almost any environment, including your body. Not all bacteria are disease-causing. What can be called pathogenic bacteria.

Ø Fungi:   

There are millions of different types of fungi in the world. Only 300 reliable

sources are still known to cause illness. Fungus is found almost everywhere in the environment, including indoors, outdoors, and on human skin. They cause infection when they are overweight. Fungus cells contain the nucleus and other structures protected by a membrane and a thick cell wall. Their structure can make it difficult to kill.

Ø Parasites:

Parasites are living organisms that behave like small animals, living or living in the 

home and feeding themselves or at the expense of the host. Although insect infections are more common in tropical and subtropical areas, they can occur anywhere.

Ø Types of pathogens diseases and description:

Ø How do pathogens spread?

Bacteria can spread in a variety of ways. Coughing or sneezing can cause germs to spread

through tiny droplets in the air. Microorganisms can also enter the gut directly when a person

 consumes contaminated food or water.

ØØ Protecting against pathogens:

1 .Wash your hands often.	2. Prepare, cook, and store meat and other foods properly.
3.Stay home when you are sick especially if you have a cold or diarrhea or vomiting. 6. Do not share drinking glasses.	4. Do not share personal items, such as razors or toothbrushes. 5. Get used to having safer sex.

Ø Antigen:

 

Molecular antigens that are able to stimulate the body's response. Each antigen has

 different facial features, or epitope, that lead to specific reactions such as the use of lymphocytes that are white blood cells of the body. In general, two main components of antigens areidentified: foreign antigens (or heteroantigens) and auto antigens (or anti-antigens). External antigens appear outside the body. Automatic antigens, on the other hand, are derived from the body.

Ø  There are 3 types of Antigen:

1	Exogenous	outside the immune system
2	Endogenous	made up of intracellular bacteria and the virus that replicates itself within the host cell
3	Auto antigens	produced by the manager Antigens that stimulate the immune system to produce lymphocytes, white blood cells that fight disease

Ø Antibodies:

        

Antibodies (immunoglobins) are Y-shaped proteins that are produced by B immune cells

in response to antigen production. Each antibody contains a paratope that sees a specific epitope in the antigen, acting as a key and key binding mechanism. This binding helps to eliminate antigens in the body, either by directly reducing or 'marking' other arms of the immune system.

 

 

Ø  Transmission electron micrograph of a human B cell, or B lymphocyte:

    As the immune system circulates, it attacks and weakens antigens similar to those that

trigger the immune response. Antibodies remain in circulation for several months, providing

 increased protection against certain antigens. Binding the antibody to toxin can reduce toxins by simply altering their chemical structure. The reaction can cause lysis (explosion) of the invading virus or attract cells that kill the microbes.

	Antigen	Antibody
Overview	Substance that can induce an immune response	Proteins that recognize and bind to antigens
Molecule type	Usually proteins, may also be polysaccharides, lipids or nucleic acids	Proteins
Origin	Within the body or externally	Within the body
Specific binding site	Epitope	Paratope

 

Ø According to new research about cancer:

 

Researchers from Cardiff University in Wales may have found a way to treat all

cancers The researchers weren’t searching for cancer therapies they were looking for

ways to fight bacteria with immune cells celled killer T cells.

 

Ø Killer T cells:

 

Cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell,

 cytolytic T cell, CD8 + T-cell or killer T cell) is T lymphocyte (a type of white cell) that kills

cancer cells, infected cells (especially viruses), or other damaged cells.

 Ø Philipp Eissmann, Imperial College, London, UK

 

    NK cells were initially recognized for their ability to kill tumor cells without recommendation or previous activation (unlike cytotoxic T cells, which need to be stimulated by antigen-expressing cells). They are called these ‘natural’ killers. In addition, NK cells secrete cytokines such as IFNγ and TNFα, which act on other immune cells such as Macrophage and Dendritic cells to increase immune response.

 While on the streets NK cells constantly interact with other cells. Whether the NK cell kills these cells or not depends on the balance of signals from the activation of receptors and the inhibitory receptors on the surface of the NK cell. Active receptors detect molecules that are expressed on the surface of cancer cells and are infected.

cells, and then ‘open’ NK cell. Inhibitory receptors act as a check in the killing of NK cells. Many normal healthy cells express MHC I receptors marking these cells as 'real'. The inhibitory receptors on the surface of the NK cell recognize MHC I cognate, and this 'shut down' the NK cell, preventing us from killing. Cancer cells and infected cells often lose their MHC I, leaving them at risk of NK cell death. Once a decision has been made to kill, the NK cell releases cytotoxic granules containing perforin and granzymes, leading to the targeting of the target cell.

Both the genes MHC I and the NK cell inhibitory receptors they detect vary widely among humans. The genes (or alleles) of these genes that a person has are linked to their ability to fight HIV infection and their risk of autoimmune diseases. NK cell types also change with age and are susceptible to chronic viral infections such as cytomegalovirus (CMV).

 Because of their ability to kill pain cells, NK cells are an attractive source of cancer-fighting agents. Some therapeutic monoclonal antibodies depend on the killing of NK cells. Researchers are also developing therapies to activate NK cells using tiny molecules or cytokines, even experiments.

 By :ZARIA NOREEN

REFERENCES:

Seladi-Schulman, J. (August 21, 2020). What are pathogens.

Macdonald, a. (2017, OCTOBER 25). technology network. Retrieved MAY 24, 2021, from IMMUNOLOGY AND MICROBIOLOGY: https://www.technologynetworks.com/immunology/articles/antigen-vs-antibody-what-are-the-differences-293550

Santos-Longhurst, A. (2019, April 03). healthline. Retrieved May 24, 2021, from Healthline website: https://www.healthline.com/health/what-is-a-pathogen

https://www.immunology.org/public-information/bitesized-immunology/cells/natural-killer-cells