Immunology Exam 2

chapter 4, 5, 6, 7

Similarities of Kappa and Gamma light chains

both pair with heavy chains, both have v and c regions, and both contribute to antigen binding site

Differences between Kappa and gamma light chains

kappa locus rearranges first, gamma rearranges only if kappa fails, gamma has multiple genes, Gamma is less common in humans(only 40%), gamma has multiple constant genes

Three most abundant antibodies in blood

IgG, IgA, IgM

Heavy chain segments

V, D, J

Light chain segments

V, J

How many antigen binding sites do T cell receptors have?

1

How many antigen binding sites do antibodies have

2

Where do RSS sequences lie?

Upstream 5' of J, Downstream 3' of V, Both sides of D

Enzyme responsible for V, D, J recombination

RAG 1 and RAG 2

What corresponds to the antigen binding site?

variable regions of heavy and light chains, CDR1, CDR2, CDR3 loops

Enzyme adding n nucleotides

TdT

Key enzyme involved in both somatic hypermutation and antibody class switching

AID

Enzyme adding N nucleotides

TdT

enzyme involved in both somatic hypermutation and antibody class switching

TdT

which of the following antibodies is the first class to be made in response to an infection and commonly exists as a pentamer

IgM

mature naive b cells co express these on their surface

IgM and IgD

Part of the T cell receptor complex and helps the t cell receptor transmit signals to the interior of the cell

CD3

mechanism used to produce either secreated antibody or the membrane bound form of immunoglobulin known as the b cell receptor

alternative splicing

results in changing of the constant region of the heavy chain of antibodies, causes change in the effector function and transports properties of antibodies.

isotope class switching

Which type of cells undergo somatic recombination

B cells and T cells

Enzyme for affinity maturation, cell activated B cells produce antibodies

AID

Process of gene rearrangement

somatic recombination

what determines immunoglobulin isotype

heavy chain constant region

How is diversity achieved

multiple V, D, J segments. somatic hypermutation

phenomenon of selecting higher affinity antibodies

affinity maturation

Antibody activity

Neutralization, opsonization, complement activation, sensitization of mast cells,

mutational mechanism producing higher affinity

somatic hypermutation

process changing constant region

isotope switching, class switching

process producing surface vs secreted heavy chain

alternative RNA processing

immunoglobulins that sensitizes mast cells

IgE

Form dimers

IgA

Forms pentamers

IgM

Properties of the t cell receptor

Heterodimer, variable and constant regions, membrane bound, CD3 complex

How does t cell receptor recognize antigen

recognizes peptide and MHC complex

Alpha beta t cells

majority, MHC restricted

gamma delta t cells

minority, not MHC restricted, innate

How is TCR diversity generated

V, D, J recombination, no somatic hypermutation, junctional diversity

what else makes up the T cell receptor complex

CD3 and zeta chains

What is antigen processing and presentation

turning proteins into peptides and loading onto MHC

Differences between MHC l vs MHC ll

MHC 1 are intracellular, and recognized by CD8. MHC 2 are extracellular and recognized by CD4

Which cells express MHC 1

alll nucleated cells

which cells express MHC 2

dendritic cells, macrophages, b cells

Why have two types of MHC

to detect both intracellular and extracellular pathogens

what does MHC bind to?

peptides, they function at cell surfaces to activate t cells