The Immune system/ virus and vaccine Flashcards
What is the transport system of the immune system
The lymph nodes
What happens when the immune system is invaded
The inate immune system is activated
1. Macrophages and dendridic cells (phagocytes) are the first on the scene and begin to eat the infection
2. Extra support is provided by Neutrophils (which are short term and leave pus)
3. Histamine molecules are released causing vasodialation – phagocytes can enter the area easier
IF the defenses are overwhelmed the adaptive immune system kicks in
1. Dendrite cells go through the lymphatic system to find Helper T cells. When the correct antibody matches with the antigen, the helper T cell clones
2. Into memory T cells and another group that goes to reenergizze the macrophages at the front line.
3. It also activates B cells (which make antibodies for any disease and killer T cells
4. B cells activate memory B cells and produce antibodies that recognize the antigen and produce antibodies
What is the first part of the adaptive immune system to be activated and what does it
The helper T cell by the dendric cell
What does a helper T cell do
They are specific to 1 antigen
- Activates memory T cells
- Activates B cells
- Activates Killer T cells
They need a lot of ATP for recruiting
What do B cells do
B cells are responsible for producing antibodies, which are proteins that recognize and bind to specific foreign substances, such as viruses or bacteria, and help to neutralize them or mark them for destruction by other immune cells.
- Antigen recognition: The first step in B cell activation is the recognition of a specific antigen by the B cell’s surface receptor. This receptor is composed of a membrane-bound immunoglobulin (Ig) molecule that can bind to a specific part of the antigen, called the epitope.
Internalization and processing: After binding to the antigen, the B cell receptor and the antigen are internalized into the B cell. The antigen is then broken down into smaller fragments, which are presented on the surface of the B cell as antigenic peptides.
Presentation to helper T cells: B cells can only be fully activated by helper T cells, which recognize the antigenic peptides presented by the B cells. This recognition occurs when the T cell receptor (TCR) on the surface of the helper T cell binds to the antigenic peptide presented by the B cell.
Co-stimulation: Once the helper T cell recognizes the antigenic peptide, it provides a co-stimulatory signal to the B cell. This co-stimulation is necessary for the B cell to become fully activated and to begin proliferating.
Differentiation: After receiving the co-stimulatory signal, the B cell undergoes clonal expansion, which results in the production of a large number of identical B cells that are all specific for the same antigen. Some of these activated B cells differentiate into antibody-secreting plasma cells, while others become memory B cells that can provide long-term protection against future infections by the same pathogen.
How does the adaptive immune system recognize so many pathogens
The immune system can recognize as many as 1 to 10 million pathogens by B and T cells mixing their code to represent possible variations found
What prevents the mutated cells in the random variation B and T antibodies from attacking the body
They go through the Thymus, Support the growth of T-cells by educating them to recognize and respond to specific antigens. It’s crucial to preventing an autoimmune reaction as it kills cells that would attack the body.
inate defense system
External barricades– skin, mucus
- Enzymes in the saliva and eye fluid, and peptides in the skin that keep cuts from getting fungi and bacteria in them
Internal defenses– fever, chemical signals, inflammation
- phagocytes, neutrophils, macrophages
- Natural killer cells – kill your own cells if theyve been infected
What are natural killer cells/ Killer T cells
patrol blood and lymph, can kill your own cells if they’re cancerous or bad
* NHC1 isn’t made in infected cells, if it detects it, it pokes it with an enzyme that triggers apoptosis (cell death)
what do histamine molecules do
cause vasodialation (signs of healing) increased temp increases cell metabolic rate
* increases permeability, and capillaries send proteins, increasing swelling, which is a good thing
* phagocytes can escape capillaries and eat bacteria
* neutrophils start to die
What happens when phagocytes get overwhelmed
they release chemicals that tap the hypothalamus and raise the body’s thermostat (fever) to burn everything, increases the metabolism of the cells, tells the liver and spleen to hold their iron and zinc so that they can’t contribute to bacterial growth
What is an antigen
something on a pathogen (bacteria virus) that the immune system does recognize (usually a protein or carb)
Why do we feel sick
Its only after the immune response has been signaled that we start feeling sick
1. Fever – makes the immune cells work better
- “calling for backup”– increased bloodflow, butrients and antibodies
- increased permiability of capilaries, so things get red and swollen from escess fluid
What are the regions of the antibodies
constant region – same for all antibodies , interacts with other immune system proteins/cells eg macrophages provides structure and interacts with others
Variable region – binds to one antigen
differences between primary and secondary immune response
secondary response is faster and higher intensity
antibiotics
target infectious bacteria
antibody
proteins made by immune cells that are used to fight pathogens
herd immunity
people who cant get the vaccine are protected because everyone else is
Antiviral
make a virus infection less severe
- they work by affecting virus replication
mRNA vaccine
- much faster development
- gives the cell the instructions to attack the virus
- mRNA vaccines work by introducing a piece of mRNA that corresponds to a viral protein, usually a small piece of a protein found on the virus’s outer membrane
Humoral Immunity
a part of our immune system that fights against infections caused by bacteria and viruses outside of our cells.
It involves the production of antibodies that can recognize and neutralize these harmful invaders.
These antibodies are released into our bloodstream and other body fluids to help prevent the spread of infections and protect us from getting sick.
Immunocompitency
the immune system can determine friend from foe
passive immunity
Temporary protection through antibodies
- By sending preformed antibodies into the blood stream
- what a baby gets from its mother
What is the size of immune cells in order
Antigen – Antibody – Virus – macrophage – vein
Virus Vaccines can be
Weakened (attenuated) - putting it through animal cells so that its slow in humans
Inactivated- usually with chemicals, more risky, can never reproduce
Protein Based - proteins from the surface of the virus are made without making the whole virus
Nucleic Acid vaccines - DNA or RNA, and only involved developing genetic material
mRNA- having our own bodies produce it, they isolate the rna of the virus and create mrna with instructions to build an aspect of the virus, could build their own spike proteins
No side effects, bc the immune system can attack without the symptoms of the virus surfacing
Which of the following is true of attenuated viruses
the virus can reproduce in non-human cells