Immunology Biology 3/4

Active immunity

body produces its own antibodies against disease-causing antigens, long term

Adaptive immunity

A specific response which is produced in response to a specific pathogen

Administrative measures for disease prevention

Changes in scheduling and work practices

Agar

The nutrient jelly on which many microorganisms are cultured. Feeds the bacteria.

Airborne (Aerosol) disease transmission

disease that is spread from person to person through droplets in the air

Allergen

a substance that causes an allergic reaction

Allergy

occurs when the body's immune system overreacts to an antigen that has been encountered previously

Antibiotic

A chemical drug that kills bacteria or slows their growth without harming body cells.

Antibiotic resistance

A bacterium no longer is affected or killed by an antibiotic due to a resistance gene

Antibody

A protein made by Plasma B cells that binds to a specific antigen. Marks specific cells for destruction.

Antigen

a molecule that is recognised by the immune system

Antigen presenting cell

engulfs, breakdown, and presents antigen to T helper cells via MHC II

Antihistamines

medications administered to relieve or prevent the symptoms of allergies; works by preventing effects of histamines

Autoimmune disease

a disease in which the immune system attacks the organism's own cells as they are seen as non self

Bacteria

unicellular, one circular double stranded DNA chromosome, produce rapidly by binary fission, produce harmful toxins which is what causes the disease

Chemical barriers

chemical barriers must be able to break bonds
animals - enzymes inside of saliva and sweat, stomach acid
plants - production of toxins. defensins, poisons

Complement Protein

innate immune system
when activated then a complement cascade will occur
lyses pathogens through membrane attack complex, makes it easier for phagocytes or other immune cells to identify pathogens

Contagious

a subset of infectious diseases that can be transferred from person to person

Cytokines

These are chemical messengers in the immune system. They are released by immune system cells to cause a specific response in a target cell.

Cytotoxic T-cells

A type of lymphocyte that kills infected body cells and cancer cells

Dendritic cell

engulf pathogens and display the antigen on its MHC Class II receptor to adaptive immune system cells, found in high numbers in the lymph nodes

Eosinophil

in high numbers during parasitic infections, allergic reactions and asthma
have granules that contain a range of substances that can be used in fighting infections

Epidemic

when a disease spreads suddenly in a specific geographic region.

Faecal-oral (Enteric) transmission

transmission involves infectious agents being spread via the feces of an individual to the mouth of another individual. Most enteric diseases are due to poor sanitation or hygiene

First line of defense

physical, microbial and chemical barriers to pathogens

Histamines

chemicals released by mast cells that increase the blood flow and cause dilation of blood vessels and increase permeability of blood vessels

Humoral immune response

activated T cells produce cytokines
cytokines stimulate specific plasma B cells that has the specific antibody for the pathogens antigen
B cells undergo clonal expansion to create plasma B cells and memory B cells
plasma B cells secrete specific antibodies to allow PLAN to occur

Infectious disease

A disease that is caused by a pathogen and that can be spread from one individual to another.

Innate Immunity

The non specific immune responses that will occur the same regardless of the pathogen encountered

Interferon

blocks/produces an enzyme that blocks the virus from reproducing

Lymphatic system

Composed of a network of vessels involved in defending the body from pathogens

Lymph node

collection of stationary solid lymphatic tissue along lymph vessels that filter lymph. The site of most antigen presentation.

Mast cells

Contain histamine and are involved in both inflammatory and allergic responses, and are found in the connective tissues

Memory cells

General term for lymphocytes that are responsible for immunological memory and protective immunity.

MHC I

major histocompatibility complex, found on all body cells except RBC

MHC Class II

A receptor expressed on the surface of APCs (macrophages

Neutrophil

These cells constantly patrol the organism for signs of microbial infections

NK cell

kill Virus infected, cancer cells through the release of cytotoxic chemicals perforin and granzymes resulting in the abnormal cell undergoing apoptosis
found circulating the blood and move into tissues

Nonspecific defence

1st and 2nd lines of defence. Can include barriers and non specific immune system cells i.e. macrophages

Pandemic

When a disease spreads suddenly throughout multiple geographic regions (countries

Passive immunity

antibodies from another organism enter the body, no memory or antibodies, short term

Pathogen

A disease causing agent, cellular or non cellular

Personal measures for disease prevention

Staying home when sick

Personal Protective Equipment

Wearing gloves

Physical contact transmission

Direct contact transmission of diseases occur with direct physical (though NOT necessarily sexual) contact such as touching

Plasma B-cells

Produces antibodies against a specific pathogen

Prion

An infectious protein that usually cause neuro degenerative diseases

Public health measures for disease prevention

Orders from health officers

Respiratory (droplet) disease transmission

occurs when infectious agents are carried from an infected person's nose or mouth via coughing

Sexual Contact transmission

transmitted through sexual intercourse and other sexual activities, referred to as STDs or STIs

Specific defence

Adaptive Immune response by B cells

Surface disease transmission

involves inanimate objects that are contaminated with an infectious agent

T helper cell

Produces cytokines that stimulate specific cytotoxic T and B cells

Transfusion (blood) transmission

blood-borne infections that occur from the introduction of a pathogen via blood transfusion

Vaccine

A harmless variant or derivative of a pathogen that stimulates a host's immune system to mount defenses against a virus

Vector

Animal that transports a pathogen to a human

vector-borne disease transmission

Allergen First Encounter

1. allergen enters the body and is recognised as non self and threatening when it shouldn’t be

2. Anitgen presentation occurs, plasma B cells are cloned and secrete a specific Ige antibody for the antigen

3. Ige is released into the bloodstream and will bind to the surface of the mast cells

4. Mast cells are now sensitised to the allergen

Virus

needs a host, either attaches to a host cell or fully enters it and injects their nucleic acid into the host cells, viruses can make changes to their surface antigens through antigenic drift and shift

Virus structure

protein coat (caspid) and nucleic acid core

Zone of inhibition

Region around a chemical saturated disc

Inflamation

1. Pathogen breaks the intact skin and enters the body which is identified as non self and initiates an immune reponse

2. cytokines are released to call neutrophils to the site of infection

3. mast cells release histamine which increase blood flow to the area and makes blood cells more permeable and dilate

4. permeable blood vessels allow the entry of the phagocytes and fluids into the tissue

5. Pus forms

6. Blood platelets release substances which allow the wound to clot to prevent further blood loss and produce a scab

Allergen Subsequent Encounters

1. Allergen enters the body and is recognised as non self

2. It bind to atleast two Ige antibodies on the surface of the mast cell

3. Mast cell releases histamine into the bloodstream and caused increased permeability and blood dilation of blood vassals.

Active Artificial Immunity

When pathogen enters the body in an artificial manner, such as receiving a vaccine

Active Natural Immunity

When a pathogen enters the body in a natural manner, such as infection by a pathogen like catching a cold

antiseptic

kills pathogen on the body like detol

disinfectants

kill surface pathogens such as bleech

non specific chemical agents

kills a variety of pathogens including virus, bacteria, fungi such as handsanitiser

Natural Killer Cells

a white blood cell that destroys infected and cancerous cells

B lymphocytes replicate to produce

plasma cells

plasma B cells

produce antibodies, defends against extracellular pathogens, cell mediated immunity, causes PLAN to occur

technical name for an antibody

immunoglobulin

non-self

antigens on the surface of the pathogen that are not recognised as belonging to the body, or self cells that have become infected or cancerous

toxoid

inactivated toxins such as from bacteria that are used in vaccines

chemical barriers for plants

Production of enzymes that can effect pathogen function or secretion of toxins, production of odors that are unfavorable for the pathogen. production of poisons and defensins

Role of complement proteins

damage the plasma membrane of bacteria and attract other cells such as macrophages to an area

role of natural killer cells

kills cells infected by a virus or release cytokines/cytotoxic granules/chemicals

Sterile

free from pathogens

How do antibodies perform their function on a molecular level

The antibody binding regions have a specific shape for a specific antigen so that for example macrophages or other immune cells can engulf and destroy it

venom inhibitors

locks onto snake/spider venom molecules and prevent them from reacting

how to antigen-antibody complexes provide protection against pathogens

immobilises the pathogen, agglutinates the pathogen, allows phagocytes to engulf the pathogen

why is making the correct identification of a viral pathogen important in the control of a disease

Specific pathogens have specific methods of transfer and might require specific methods of control such as a particular antiviral drug. Incorrect identification can lead to continued infections and spread
Identify pathogen and isolate antigens, enabling the production of a vaccine or produce a drug with a complementary shape. If the majority of the population was vaccinated or treated with this rational drug, this would greatly reduce the transmission of the disease.

creation of a vaccine

• modify a pathogen so that it isn’t harmful and won’t cause damage

• Then it’s injected into the body to create antibodies and memory cells

herd immunity

occurs when majority of a population or community develops immunity against a contagious disease either through vaccination or previous infection, greatly decreasing the likelihood of transmission from person to person

consequences based approach

doing actions that have the most positive outcome on the majority of people regardless of whether it’s right or wrong

duty/rules based approach

people have an obligation to follow a rule/law/moral duties regardless of the consequences

virtues based approach

the need to consider the virtues/moral character of a person carrying out the action

principle of justice

actions involving equality

principle of integrity

actions involving truth and trustworthiness

principle of beneficence

actions that minimise harm and have a positive outcome

principle of non maleficence

avoiding actions that lead to harmful consequences

principle of respect

considering autonomy

what makes a pathogen non living

• unable to undergo cellular processes such as protein synthesis or cellular respiration

• requires a host to replicate DNA

• Non cellular, meaning not made of cells

disease

a change that impairs the function of an individual
can be genetic, deficiency, environmental, pathogens

cellular pathogens

bacteria, fungi, protists

non cellular pathogens

viroids, prions, viruses

viroid

infectious particle, single stranded short pieces of RNA, no protein coat, plant pathogen, competes for nucleotides in plants and form viroid bundles
eg - potato spindle tuber viroid

prions

infectious proteins with abnormal shape, normal proteins can become abnormal through contact with abnormal one, hard to destroy but can be destroyed by heat or protease
can cause degenerative neurological disease, prions destroy neural tissue making them holy and spongey, neuro messages can’t get through for long and causes death quickly
eg - mad cow disease

protists

unicellular, live in colonies or on their own
eg - protozoa, cs8drd gastro in animals, mildew

fungi

uni or multicellular, heterotrophic the need to obtain nutrients from an external factors, yeasts, molds, ringworm