Intro. To Immunology Flashcards
Difference between adaptive and innate immunity. What type of cells make up each type of immunity
Inmate-first line of defence when there is a new antigen. NK, phagocytes
Adaptive- strengthens with each encounter of the same antigen
T-cell, b-cell
Where do b-cell and t-cells come from? How about myeloid cells?
Common progenitor lymphoid
Common progenitor myeloid
What do NK cells target?
Downregulated mhc clas, viral infected cells
What are complement systems made up of and what is their main function?
They are made up distinct plasma proteins, that can opsonize a bacteria for engulfment by phagocytosis, it can directly kill them or acts chemoattractants
What does the postulates of the clonal selection theory state
That each lymphocyte has a specific receptor for an antigen, the higher the affinity the more likely it will be activated, its colonies will have the same exact receptor. The lymphocytes that have receptors against self molecules are deleted at an early stage
Difference in antigen bonding site between t-cell and b-cell?
B-cells have 2+surface immuglobulin
T cells have 1
Where are the t-cells and b-cells made? Where do they go?
Thymus
Bone marrow
Lymph tissues
Where do antigens go?
Lymph nodes where they meet naive lymphocytes
How are b-cell activated? What happens after it’s activated?
Antigen receptor binding(signal 1) binds to antigen internalizes it and process it and present it on mhc class 2, and activation by t-cell(signal2). T-cell binds to antigen on mhc class 2 activates B cell where it Proliferates, differentiation to antibody secreting plasma cells and memory cells
Outline b-cell migration
Develop in bone marrow, go to lymph node and leave through efferent node, the antibody secreting B cells go back to bone marrow
Effector functions of B cells
Neutralization, opsonization, complement
What induces isotope switching in B cells?
Different cytokines activate and inhibit
What is somatic hypermuation?what is the result of it?
Rearrangement of antigen binding site after it re encounters an antigen, it is mutated in a high frequency resulting in differentiated antibodies that have higher affinity and ones that have lower affinity
How are t-cell activated? What happens to t-cells after activation?
T-cell signal 1-mhc peptide on APC
Signal2-costimulatory signal from APC(cd28&cd80/86)
Proliferate differentiate to effector T cells, leave lymph node and go to the body
Is activation of t-cells in the site of infection? how do dendritic cells work?
No
They’re immature when they encounter an antigen it binds to it, it migrated to lymph node where it will mature and present antigen to lymphocytes and then it stop processing antigens
Do people have different phenotypes of mhc class 1 and 2?and how many hla phenotypes do they inherit from each parent? Why is there this variation?
Yes, 3 from mom and 3 from dad, because they have different peptides that some are adept to binding to compared to others.
What’s the difference between mhc class 1 and 2?
Class 1- binds to endogenous antigen and to CD8 cells
Class 2- binds to exogenous antigen and to cd4 cells
Requirement for CD8 epitopes? CD4 epitopes?
9 amino acid peptide, closed groove and mhc class 1 Open groove
What are they types of APC
Dendritic cell. B cell, macrophage
What do th cells activate and recruit?
B cells, NK cells, granulocytes and macrophage
What cytokines make cd4 cells differentiate into th1 cells? Th2 cells? What cytokines do they release in turn? What cells do they activate And what kind of immunity is th1 and th2 cells part of?
Il-12. Ifn gamma, tgfb, il-2, macrophages, cell mediated immunity
Il-4. Il-4, Il-5, il-10, b-cells humoral immunity
How do CTL cells kill target cells directly?
By granzyme or perforin,toxins, interferon gamma and tnf,fas
Do effector cells need costimulation?
No
