Antibody Structure and Function

Question 1

What is humoral immunity?

Answer 1

adaptive immune system. B cells turn into plasma cells, which create antibodies. These antibodies can bind to any molecule.

Question 2

What is cell-mediated immunity?

Answer 2

adaptive immune system. T cells can be helper T cells or cytoxic T cells

Question 3

What are the types of lymphocytes?

Answer 3

T cells and B cells

Question 4

What is neutralization with antibodies?

Answer 4

Antibodies bind to virus that stop the virus from being able to bind to/interact with cells receptors

Question 5

What is opsonization with antibodies?

Answer 5

antibody Fab region binds to microbe. The phagocyte recognizes and the receptor binds to the Fc region of the antibody. It then internalizes the whole thing and destroys the microbe.

Question 6

What is complement fixation of antibodies

Answer 6

Antibodies bind to microbe which then allow complement proteins to also bind/clump to kill the microbe.

Question 7

What is Antibody-Dependent Cellular Cytotoxicity (ADCC)

Answer 7

antibody binds to spike proteins on outside of infected cells. A NTK (natural killer cell) will bind to the antibody and destroy the sick cells by releasing granules.

Question 8

Explain the antibody structure

Answer 8

2 arms (Fab region) and 1 tail (Fc region). The Fab region is the antigen binding site. There is a heavy chain and light chain on both arms. the tail only has a heavy chain.
The variable domain is the part of the Fab arm region that is different based on the binding site for antigens.

Question 9

antibody that is the foot soldier of the immune system

Answer 9

IgG

Question 10

antibody in charge of allergies

Answer 10

IgE

Question 11

low affinity antibody with lots of binding sites

Answer 11

IgM

Question 12

antibody in the gut against gut microbes

Answer 12

IgA

Question 13

difference between variable domain and constant domain of antibody

Answer 13

Talking about the Fab region of arm (heavy and light chain). The variable domain is the one that varies antibody to antibody that is the antigen binding site. The constant domain doesn’t change.

Question 14

Immune Complexes when antibodies cause diseases

Answer 14

antibodies bind to self antigens and will form “immune complexes” that deposit/bind to the inside of blood vessel walls.

Question 15

What is the J chain?

Answer 15

connects antibodies together in IgA and IgM

Question 16

Complement Fixation when antibodies cause diseases

Answer 16

antibody binds to antigen of cell. C1Q complement protein binds to antibody and causes lysis of the cell

Question 17

Inflammation when antibodies cause diseases

Answer 17

antibody binds to antigen of cell. C1Q binds to antibody and releases inflammatory complement proteins. These bind to the endothelium cell wall and cause neutrophils to come out of the blood and bind to the antibody tail (Fc)….but they can’t do phagocytosis! So “frustrated phagocytosis” happens where neutrophils release granules, which kill the affected cells.