The Infectious Diseases and Human Immune System
We are going to discuss “The Human Immune System and Infectious Disease”
A disease-causing agent can attack any living thing. There are systems to defend against infection by viruses even in bacteria, which can fit more than a million on the head of a pin. Virus defence technology improves with the complexity of organisms.
The immune system of multicellular animals contains cells and tissues that are specifically adapted to combat the infection. In some cases, these responses immediately happen, allowing the infection to be contained quickly. Other responses are slower, but they focus on the particular pathogen. Together, Known as the immune system, these reactions are the body’s defence mechanism. It is critical to our survival in a world full of potentially harmful bacteria that even a minor weakening of one arm of the human immune system can put us at risk for serious, or even life-threatening infections.
Immunity (Innate) without specificity
Specific immunity and non-specific immunity are two levels of immunity in the human immune system. Humans are able to protect themselves against harmful substances through non-specific immunity. Small and huge species alike might be targeted for destruction. Pathogens are a group of organisms that cause disease in their hosts.
Difese immunitarie is innate in all animals against common pathogens. Outer barriers like the skin and mucous membranes are the first lines of defence. When pathogens breach the outer barrier, such as through cuts in the skin or inhalation into the lungs, they can cause serious health problems.
Phosphophagocytes (white blood cells, WBCs) are capable of fighting pathogens that manage to pierce outer defences. Phagocytes surround pathogens, ingest them, and neutralize them.
Immunity to certain diseases
In addition to being critical to good health, healthy phagocytes are incapable of addressing certain infectious threats. The innate immune system’s phagocytes and other components can be supplemented by a particular immunological response.
Specific immunity is different from innate immunity in that it targets a specific pathogen. There are no specific immune responses in invertebrates.
Lymphocytes are one type of white blood cell That is essential to a particular immunological response. Bone marrow is the source of lymphocyte production, and there are numerous subtypes of lymphocytes. T and B cells are the two most frequent types of cells in the human body.
Antigens are foreign particles that trigger an immune response in the body. Millions of different antigens are specific to B and T cells in the human body. Antigens are usually associated with microbes, but they can also occur in other environments. People who receive blood transfusions that are not compatible with their blood type can experience reactions from T and B cells.
In order to better comprehend T and B cells, look at the following: A single characteristic distinguishes B cells from all other immune system cells. Plasma cells can be formed from the developed cells, and these cells create an antibody, a protein. Antibodies can only recognise specific antigens. B cells, on their own, do not produce good antibodies, and they must be stimulated by T cells to begin maturation. When it detects the antigen to which it is trained to respond, a well informed B cell will produce a large number of plasma cells.
A large number of antibodies are then secreted by the plasma cells, which are directed against specific blood antigens. Activated T cells are triggered by antigen-presenting cells (APCs) that display the antigen they are specific for. Blended cells (mostly human, but containing an antigen for T cells) are a trigger for certain elements of immune responses.
The T helper cell subtype plays a variety of roles in the immune system. T helper cells release chemicals that help the immune system fight infection
- Support the division of plasma cells by activating B cells
- Microbes are destroyed by phagocytes
- Killer T cells must be activated
The body’s organs and tissues
In addition to circulating in the blood, specific immune cells can also be found in several different organs. Within the organ’s immunological tissues, immune cells are formed, infections are halted, and immune cells are able to communicate with each other. All of these organs and tissues are part of the body’s immune system.
Infections and diseases
Pathogens cause infection when they invade body cells and multiply. The immune system usually responds to infection. Quick and effective action will eliminate or contain the infection so quickly that it cannot cause disease.
The disease can sometimes be caused by infection. (The focus of this chapter will be on infectious disease, which we define as symptoms or signs of sickness as a result of an infection). Infectious diseases may occur when immunity is low or impaired, when pathogens are virulent (effective at damaging host cells) or when there are many pathogens in the body.
There is a wide range of symptoms associated with infectious diseases. When the body temperature rises, the immune system responds and the environment becomes hostile for pathogens. White blood cells are attacking and releasing substances involved in the immune response when they cause inflammation or swelling, in the infected area.
In order to create memory B and T cells specific to a particular pathogen, vaccinations work to stimulate an immune response. Memory cells remain in the body and can help the body respond quickly and effectively to the pathogen if it encounters it again in the future.