Exam 2 - Dr. Woolums Material

T lymphocytes are key players in what immune response?

Adaptive

What immune response mediates memory Reponses to specific agents?

Adaptive

B-cells and T-cells recognize different forms of the _____ antigen

Same

WherePRR are the germline encoded broad receptors that recognize DAMPS/PAMPS, which is mediated by a variety of cells against a wide range of pathogens?Whare are the germline encoded broad receptors that recognize DAMPS/PAMPS, which is mediated by a variety of cells against a wide range of pathogens?

PRR

What are the gene rearranged two receptors of the adaptive immune response that are highly specific, can only recognize a single molecule, and is mediated by antigen specific lymphocytes?

TCRs and BCRs

PRR is germline is encoded.  When were they formed?

Embryo formation

Can TCRs undergo hypermutation or something equivalent?

No

What receptors are highly specific?

TCRs and BCRs

What receptors undergo gene rearrangement?

TCR and BCR

What receptors are germline encoded (do not change)?

PRRs

What receptors have a broad specificity?

PRRs

What is a major difference within the constant region of the TCR and BCR?

No isotype switching

How many binding sites do TCR have?

1

T/F Both TCR and BCR are heterodimers

TRUE

What do the small insertions or deletions of nucleotides of at the joints between gene segments of TCRs further contribute to?

Diversity

T/F Antigen stimulation promotes change in TCR

FALSE

Do TCRs undergo hypermutation?

No

T/F Once TCRs are activated, they do not change

TRUE

How many different combinations of gene segments are there that comprise the cast diversity in the TCR repertoires?

Several million

T/F Germline alpha and beta chains combine to create gene diversity of TCRs

TRUE

If either RAG gene is disrupted or mutated, B and T cells development is completely abolished this causing what?

Severe combined immunodeficient (SCID)

What is SCID caused by?

RAG gene disruption or mutation

What imitates V(D)J recombination by nicking double stranded DNA?

RAG-1 and RAG-2

What was the immunological analysis of SCID in Frisian Water Dogs that had an issue with fighting disease?

Missense mutation in RAG-1

What was the immunological analysis of SCID in Arabian foals?

Incapable of V(D)J gene rearrangement

 CD4 and CD8 Tell cells express TCR that is made up of what two components?

Alpha and beta chain

What transmits the signal that initiates the signal transduction cascade when TCR binds to an antigen?

CD3

What distinguishes alpha, beta cells from T cells that have a receptor made up of a gamma and a delta chain?

Alpha beta TCR

Which has more diversity (generally): gamma delta TCR or alpha beta TCR?

Gamma delta

Where are gamma delta cells well represented?

Peripheral blood mononuclear and afferent/efferent lymph

Where are gamma delta cells rarely found?

Lymph node parenchyma, spleen, payer's patches, and thymus

What stimulates only a small subset of all t-cells?

Pathogen

What does a single T cell response to?

Tiny fragment of a pathogen

What do APCs look for?

MHC class II

What do t cells look at?

Antigen fragment

What transmitted the signal that initiates the signal transduction casvade that results when TCR binds to antigen?

CD8

What is an encoded molecules that is in a cluster of closely linked genes?

MHC

What T cells exhibit both innate and adaptive immune behaviors?

gamma delta t cells

Which is more diverse: gamma delta t cells or alpha beta t cells?

alpha beta t cells

What class of MCH get recognized by CD8 cells?

Class I

What do healthy cells present to APCs?

MHC Class II

MHC in humans?

HLA

What doctor won the nobel prize for his studies on MHC?

Doherty

What allows cytotoxic t cells to kill target cells only?

MHC restriction

What do cytotoxic t cells to look for on target cells?

MHC Class I

T/F essentially every cells has MHC Class I

TRUE

Where is MHC Class 1 generated from?

inside the cell

What type of processing does MHC 1 undergo?

endogenous

Where is MHC Class II generated from?

outside of the cell

What type of processing does MHC II undergo?

exogenous

What type of peptide-binding sites on MHC molecules are capable to binding peptides of many different amino-acid sequences?

Degenerate binding specificity

What is the peptide binding sites of the surface of MHC molecules that allow for a single peptide to be tightly held by non-covalent bonds?

peptide-binding groove

How many peptides fit into MHC I groove?

8-11 amino acids

How mant peptides fit into the MHC II groove?

12-25 amino acids

What is the individual that inherited two different alleles of the genes from parents?

heterozygous

What is the individual that inherited two different alleles of the genes from parents?

Homozygous

What is the particular combination of MHC alleles found on a given chromosome?

HMC haplotype

What is the combination of all MHC alleles that an individual has?

MHC type

What is a downside of extreme heterozygous MHC alleles?

Higher chance of autoimmune response

What can delay the progression of AIDs in people infected with HIV-1?

MHC heterozygosity (both MCH class I and II)

What is it called when an animal population are very homogenous?

genetic bottlenecking

What can genetic bottlenecking increase the risk of?

decimation by infectious pathogens

The diversity of peptides that can be presenting by the human or animal population as a whole is further increased by what nature of MHC class I and class II genes?

polymorphic

In the instance of transplants, what can cause a strong T cell response against the transplant?

MHC polymorphism

Where do lymphocyte progenitor cells (B or T cels) travel to in order to develop into naive t cells?

primary lymphoid organs

Where do T cells become fully devloped?

thymus

Where do B cells become fully developed in birds?

bursa of fabricius

Where do b cells become fully developed in ruminants?

peyer’s patches

Where b cell become fully developed in anything but birds and ruminants?

bone marrow

Where do fully developed naive T and b cells travel to become activated in order to fight infections?

Secondary lymphoid organs

What lymphoid organs cannot be removed without causing a loss of lymphocytes thus making your patient more prone to infection/disease?

primary lymphoid organs

What type of lymphoid organs can be removed without causing major or minor loss of lymphocyte production?

secondary

What are examples of primary lymphoid organs?

thymus, bursa, peyer’s patches

What are examples of secondary lymphoid organs?

spleen and lymph nodes

What is this an image of?

Bursa of fabricius (primary lymphoid organ)

What is pointed out in black?

Follicle of bursa

What is the dark outer layer that houses lymphocytes, macrophages, and plasma cells?

Cortex

What is the lighter inner area that is the epithelial cells surrounding lymphocytes?

medulla

What can be found in the medulla of the bursa follicles?

epithelial cells

What can be found in the cortex of the bursa follicules?

Lymphocytes, macrophages, and plasma cells

In birds, what is the primary B cell lymphoid organ?

bursa of fabricius

In ruminants, what is the primary B cell lymphpid organ?

peyer’s patches in the ileum

In everything but birds and ruminants, what is the primary b cell lymphoid organ?

bone marrow

What are clusters of lymphatic tissue in the ileum?

Peyer’s patches

What is this an image of?

thymus

What is the section pointed out?

Lobules

What is the dark outer area that houses lymphocytes, macrophages, and plasma cells?

Cortex

What is the inner light area that is epithelial cells of the lobules within the thymus?

medulla

When is the thymus fully devloped?

at birth

What happens to the thymus as one ages?

involution

Why doesn’t involution compromise t cell immunity in adults?

t cells are long-lived or slef-renewing

Once t cells are primed (experience an antigen), what occurs?

clonal expansion

What secondary lymphoid organ is everywhere?

lymph node

What secondary lymphoid organ is in the abdomen?

spleen

What secondary lymphoid organ is under the pharyngeal muscosa?

tonsilsa

What secondary ly,phoidc organ is under the small intestinal mucosa in the jejunum and ileum?

Peyer’s patches

How do primed T cells leave the lymph node to go to the bloodstream?

efferent lymphacitcs

Where in the lymph nodes do Naive t cells wait to meet dendritic cells that present antigens?

paracortex

Where in the lymph nodes do native b cells go to be primed by antigens in lymph?

cortex

Where do antigens and sentinel cells enter the lymph node?

afferent lymphatics