lecture 33

Question 1

all three complement starting pathways leads to what intermediate

Answer 1

C3 convertase

Question 2

what are the three methods of communication between the innate and adaptive immune system

Answer 2

soluble molecules, cell surface receptors and antigen

Question 3

what are the two chemical signal tpyes for chemical signals on cell surface receptor path

Answer 3

they are cytokines and chemokines

Question 4

what examples of chemical signals binding to cell surface receptors

Answer 4

PAMPS binding to toll-like receptors

Question 5

describe cell communication through cytokines

Answer 5

these cytokines can bind to cytokine receptors on other cells. Cytokine produced by one cell in response to a pathogen can be detected by another at the cytokine receptor of another cell. The binding of the cytokine will then have transcription effects on the receptor cell to help it fight the invading pathogen.

Question 6

whats a cytokine and example

Answer 6

Cytokines, for example interleukens and interferons, these are molecules that affect the growth and activity of immune cells.

Question 7

describe cell communication through chemokines

Answer 7

When a chemokine binds to a chemokine receptor on the cell surface there is signalling to the nucelus to change aspects of DNA transcription and translation. Chemokine receptor activates molecules that direct movement, the chemokine receptors will help the cell follow chemokine trails, undergoing positive chemotaxis.

Question 8

describe communication through Cell surface-bound receptors binding to cell surface-bound ligands

Answer 8

For example helper T cells will link with our B cells to activate them. The interaction between surface bound receptors will change the function of the cells with the ligand and the cells with the ligand receptor or both.

Question 9

describe communication through Antigen being presented to a cell surface-bound receptor

Answer 9

An example of this is dendrites. The dendrites are phagocytic. When they break up the phagocyte they consume a pathogen, and they make an antigen. The dendrite then shows this antigen to a T cell, activating it.

Question 10

whats an antigen

Answer 10

anything that can be recognised by the immune system.

Question 11

whats a foreign antigen

Answer 11

something from the outside of the organism that can be recognised.

Question 12

whats self-antigens

Answer 12

things within the body that immune cells are tolerant of.

Question 13

what are the major receptors on cells

Answer 13

major histocompatibility complexes

Question 14

what antigen do MHC-1 present

Answer 14

endogenous antigen, endogenous antigen: is a peptide made from an internal protein. So virus proteins that have been made in the cell are broken down but then are degraded into peptides. Or cancerous cells whose mutated DNA is used to make mutated proteins and then peptide antigens.

Question 15

what antigen do MHC-2 present

Answer 15

exogenous antigen, so antigens from peptides of cells that have been phagocytosed into the cell

Question 16

what cells have MHC-1 and what have MHC-2

Answer 16

all nucleated cells have MGC-1, all cells except red blood cells. MHC-2 is on Antigen-presenting cells, APCs are like dendritic cells, macrophages, and monocytes.

Question 17

APCs are from what lineage

Answer 17

the myeloid lineage

Question 18

how do helper T cells activate the b cells by

Answer 18

Making cytokines that bind to receptors on the B cell membrane.
Helper T cells also have surface bound receptors that bind to a b cell surface bound ligand.
This communication leads to activation of the B cell, and helps the B cell to make antibodies