lecture 5

Question 1

what are the properties to adaptive immune response?

Answer 1

specificity, diversity, memory, clonal expansion, specialization, contraction and homeostasis, nonreactivity to self

Question 2

what are examples of the immune system cells?

Answer 2

T and B cells are lymphocytes
dendritic cells, macrophages, B cells, and follilcular dendritic cells are antigen presenting cells
lymphocytes, granulocytes (neutrophils, eosinophils) and macrophages are effector cells

Question 3

what is humoral adapative immune response?

Answer 3

antibodies that circulate in blood, can recognize the infected cells and free microbes

Question 4

cellular adaptive immune response?

Answer 4

lymphocytes t cells dont produce a soluble product, t cells can recognize the infected cells but not free microbes

Question 5

which lymphocyte is the membrane bound antibody?

Answer 5

the B cell antigen receptor is membrane bound, surface immunoglobulin. T cell is not, t cell antigen receptor

Question 6

what are the small antigen fragments bound to in t cells?

Answer 6

normal cell surface proteins called MHC molecules

Question 7

what is antigen presentation?

Answer 7

when infected cells produce mhcs that bind to antigen fragments and are transported to the cell surface

Question 8

what are some central lymphoid organs?

Answer 8

thymus- t cell maturation, bone marrow- b cell maturation

Question 9

what are some peripheral lymphoid organs?

Answer 9

lymph nodes, spleen white pulp, mucosa associated lymphoid tissue- t and b cell activation, antigen trapping

Question 10

what is acquired immunity?

Answer 10

the adaptive immunity provided by immunological memory

Question 11

what are the effects of b lymphocyte?

Answer 11

neutralization of microbe, phagocytosis, complement activation, production of plasma cells

Question 12

effects of helper t lymphocytes?

Answer 12

activation of macrophages, inflammation, activation of t and b lymphocytes

Question 13

cytotoxic lymphocyte effects?

Answer 13

killing the infected cell, virus cells

Question 14

what are the two instances where antibodies dont work well?

Answer 14

dont work well with hiv and intracellular pathogens

Question 15

what does clonal selection of B cells generate?

Answer 15

a clone of short live activated effector cells and a clone of long lived memory cells

Question 16

clonal selection theory accounts for…

Answer 16

diversity, self/non self discrimination, and memory

Question 17

what is the make up of immunoglobulins?

Answer 17

2 heavy chains, 2 light chains, Fab, Fc where antibodies are defined

Question 18

describe the 5 classes of antibodies

Answer 18

IgD-unknown,
IgG-major form of antibody circulating in blood,
IgM-memrbane bound formis the receptor on B cells, also circulates in blood
IgE-involved in allergic reactions and defense against parasites
IgA-found in secretions, first line of defense against pathogens

Question 19

difference between IgG and M

Answer 19

M primarily activator in complement system. G can do that too but can play further effector mechanisms through Fc on phagocytes, eosinophils and mast cells

Question 20

how is antibody diversity created?

Answer 20

B cells start off with same DNA as any other cell, as B cells mature the antibody DNA changes, heavy chain variable region encoded in 3 gene segments (V D and KJ), light chain variable region encoded in 2 gene segments (V and J), mix and match at random

Question 21

steps to B cell maturation

Answer 21

immature b cell has not rearranged DNA for B cell receptor, naive b cell expresses a membrane bound antibody on its surface but hasnt encountered antigen, mature b cell undergone class switching, affinity maturation, and secretes an affinity matured antibody

Question 22

what can antibodies do?

Answer 22

can block entry of a microbe into a host cell or prevent virus from replicating, can tag invaders for destruction, DONT directly kill anything

Question 23

how are some ways pathogens evade antibodies?

Answer 23

change one antigen residue to prevent binding, mutate rapidly so antibodies dont react with new strain, and enter a cell so antibodies cant do anything

Question 24

how are monoclonal antibodies used in medicine?

Answer 24

used to detect presence and or quantity of an antigen, used to purify antigens, increasingly used for medical applications like cancer