Immune system 1 - MT2 - Part 3 Flashcards
What type of cells are lymphocytes?
Adaptive cells
Where are lymphocytes derived from?
Stem cells in the bone marrow
Where do B lymphocytes (B cells) mature?
In the bone marrow
What type of cell are B cells?
White blood cells
What is the function of B cells?
They function in the humoral immunity component of the adaptive immune system by secreting antibodies
Where to T lymphocytes (T cells) mature?
In the thymus
What type of cell are T cells?
White blood cells
What role do T cells play?
They play a central role in cell medicated immunity
What do B cells have on their surface and what do they serve as?
Antibodies, that serve as antigen receptors
What does the binding of an antibody tell the cell?
That there is a foreign molecule out there with the specificity to bind to that antibody
How are B cells activated? (2)
- Antigen binding
2. Interaction with a helper T cell
How are B cells educated?
As they mature
- they learn as they go
What happens if B cells are not activated?
They circulate around and do nothing until they are activated
How long do plasma cells last?
Not very long
- days or weeks
Plasma cell
Is a fully differentiated B cell that produces a single type of antibody
How long do memory cells last?
Forever
Memory cell
Is a long lived lymphocyte capable to responding to a particular antigen on its reintroduction, long after the exposure that prompted its production
What do antibodies do?
They coat viruses and bacteria which prevents their attachment to epithelia and allows them to be recognized for degradation
- needs to have some sort of recognition of the viruses (it needs to be invited in)
CD4
Is a glycoprotein found on the surface of immune cells
What are 3 examples of CD4?
- T helper cells
- Monocytes
- Macrophages
What do helper T cells do?
Provides links for communication
- links are between macrophages, humoral immunity and innate immunity
Macrophages
They are antigen presenting cells (APCs) that are molecules of the major histocompatibility complex (MHC) presents the antigen to the cell
What are critical cells for the immune system?
Macrophages
- communicates innate and adaptive system
What can an activated helper T cell do?
Can activate B cells and cytotoxic T cells
Cytotoxic T cells
Is a type of WBC that kills cancer cells that are infected, or cells that are damaged in other ways
Humoral immunity
Is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as antibodies
Innate immunity
Immunity that is naturally present and is not due to prior sensitization to an antigen form
- for example an infection or vaccination
What are cytotoxic T cells activated by? (2)
- Helper T cells
2. Infected cells
What do cytotoxic T cells do?
They poke holes in the plasma membrane of the target cell and the contents then leak out of the cell
Perferin
Can form larger channels in the membrane of the cell, but these channels are not gated
What do granzymes do?
Chew up material
How do viruses reproduce?
By introducing genetic information in the cell and having that be expressed
