Immunity Flashcards
What is the immune system?
The complex network of organs, cells, and molecules that work together to protect the body from infection
What is the lymphatic system?
helps remove waste products, bacteria, and damaged cells from the body, and provides an important defense against infections
Circulatory
Responsible for transporting blood, nutrients, and waste throughout the body
Main functions of lymphatic system
immune defense and waste removal
Major structures in the lymphatic system
lymph nodes, spleen, thymus, and tonsils
What does the lymphatic system do?
provides a route for excess fluid in tissues to return to the blood
What is lymph?
Colorless fluid containing white blood cells, found in tissues and drains through the lymphatic system into the bloodstream
What do lymphs contain?
waste products, cellular debris, bacteria, and proteins, as well as lymphocytes!
Lymphocytes
Majority of cells in lymph, a type of white blood cell
What is innate immunity?
Provides immediate, non-specific defense against pathogens, like the first line of defense (blocks the spread of pathogens through out body)
What is considered innate immunity?
physical barriers like our skin and stomach acid, as well as cells like macrophages and dendritic cells that attack pathogens
What is adaptive immunity?
More specific and develops after exposure to a particular pathogen
What is considered adaptive immunity?
involves specialized cells called B and T lymphocytes which can recognize and attack specific pathogens
What are antigens?
a substance from the surface of pathogen
What are antibodies?
a blood protein produced in response to and counteracting a specific antigen
What is the Major Histocompatibility Complex (MHC)?
- a locus on DNA that codes for cells surface proteins essential for the adaptive immune system
- Helps our immune system recognize and destroy infected cells (MHC I) or harmful pathogen (MHC II)
MHC 2
antigens from outside cells
MHC 1
antigens from inside cells
Ex. viruses that have infected the cell
Where is MHC 2 found?
Found on special immune cells called antigen-presentings cells (APCs)
Where is MHC 1 found?
Found anywhere in the body
What are T cells?
Special immune cells that recognize the antigens and trigger an immune response
How many cells can each T cell recognize?
Only recognize a specific sequence of a song peptide which helps the immune system target the specific antigens that are causing the infection
B Lymphocytes
a type of white blood cell responsible for producing antibodies
Do B lymphocytles connect to the immune system?
Yes, to the adaptive immune system
Where does B cell development begin?
the bone marrow
What happens when B cells grow up?
mature and differentiate into antibody secreting cells called plasma cells also known as effector B cells
Where do b-cell development migrate too?
Secondary lymphoid organs like the spleen
What is the order of B cells?
Antigen present–>B cell releases antibody–>antibody binds and neutralizes antigen
B-cells can remember…
specific antigens
The memory of B-cells means…
a faster and more effective response if the pathogen enters the body?
How is understanding B-cell development and antibody production crucial for advancing knowledge of immunology and developing new treatments for disease?
B cells remember antigens, use that to help prevent specific diseases. Knowing this helps us know how our body reacts to disease, which can allow for us to try and use these B cells to help people who can’t themselves
What is cell mediated immunity also known as?
Cellular immunity
Does cell mediated immunity involve antibodies?
NO
How does cell mediated immunity work?
Activation of specific immune cells and the release of cytokines in response to an antigen
How is cell mediated immunity effective against?
Virus-infected cells, cells with intracellular bacteria, cancer cells displaying tumor antigens, and even delayed transplant rejection
How does cell mediated immunity begin?
With activation of naive T cells (haven’t encountered an antigen yet)
What happens when a naive T cell encounters antigen-presenting cells (APCs)
Converted into activated effector T cells
What do APCs do and what are some examples?
Macrophages and dendritic cells (killers), are presnt antigenic peptides to receptors on T cells, initiating the immune response
What does the memory T and B cells do?
Recognize and respond to antigens that the body has encountered before
Why are the memory of T and B cells good?
Faster and more robust immune response, preventing reinfection by the same pathogen
Vaccination are…
based on the concept of immunological memory
What is a vaccine?
the system is exposed to a weakened form of the pathogen or part of pathogen to develop immunological memory without causing the disease
What do vaccines do?
stimulates the production of memory cells
The strength and duration of vaccine induced immunological memory can be influenced by various factors such as…
Age, genetics, and the nature of the pathogen itself
Requiring multiple vaccination helps to create…
long-lasting immunity, while others may mutate and evade existing memory cells
