immunology Flashcards
How does a macrophage destroy a pathogen?
Phagocytosis. Macrophage engulfs pathogen through digestive enzymes and becomes a APC
How does a macrophage interact with T helper cells?
T helper cells have specific receptors that attach to macrophage and become “activated T helper cells” and release cytokines to begin to mass produce t helper cells and macrophage
What does a B lymphocite receptors attach to?
pathogen- becomes APC
What does T helper cell release to activate B Cells?
chemicals
Whats it called when B lymphocites replicate?
Clonal expansion
What do Plasma Cells do?
create identical antibodies that bind to the antigens on pathogens
What can b lymphocites differentiate into?
plasma cells and B memory cells
What is the primary immune response?
Plasma cell antibodies- may take days or weeks to develop so symptoms may appear
What are memory cells?
Involved in secondary immune response and remain in body after primary infection
How are memory cells used in the secondary immune response?
Convert to plasma cells when infected a secondary time- faster and destroys pathogen faster so less symptoms
What type of virus is HIV?
RNA Virus
What type of drugs are used for a viral infection
Antiviral
What do antiviral drugs do
prevent functions of enzymes for viral RNA to replicate into DNA like reverse transcriptase
What is the function of reverse transcriptase
Convert viral RNA to viral DNA
What does HIV target
T helper cells
How does a virus enter the host cell
Attachment proteins on the virus attach to a molecule on the surface of helper t cells
What happens when a virus capsid enters the cell
Viral RNA is converted to Viral DNA through use of the enzyme reverse transcriptase
what happens when HIV DNA in the nucleus becomes activated
produces mRNA encoding viral proteins, moves into cytoplasm where it is transcriped by ribosomes into viral proteins the bud from helper T cell
Why do the helper T cells die during viral replication
integrates into the host cells DNA and uses the cell to make new viral particals that break out and damage host cell
what can death of helper t cells lead to
AIDS
What happens when a person gets AIDS
their immune system can no longer function properly as thry cannot produce antibodies by b lymphocites and cell mediated becomes less effective
what is the humoral response
antibodies released by plama cells (B lymphocites)
what is the cell mediated response
role of t lymphocites- helper T cells and killer T cells
What does a t lymphocite do
Have receptors to recognise “non- self” specific antigens
