What are the 2 central lymphoid tissues?
Thymus gland and bone marrow
What are the 3 peripheral lymphoid tissues?
Lymphnodes, peyers patches (ileum), spleen
Where is the site of B-cell localization and proliferation in a LN?
follicle
Where are the T-cell in a LN?
paracortex
What is found in the medulla of the LN?
medullary cords (closely packed lymphocytes and plasma cells)
The role of B-lymphocytes is categorized as what kind of immunity?
humoral
What is produced with humoral immunity?
antibodies
The role of T-lymphocytes is categorized as what kind of immunity?
cell mediated
What kind of chemical activates components of immune system (i.e. activates macrophages, PMNs, etc)?
lymphokines (subset of cytokines produced by lymphocytes)
what is the function of basophils?
they function in the inflammation response by releasing histamine and other chemical that act on the blood vessels.
what is the function of eosinophils?
they destroy parasitic organisms
what is the function of neutrophils?
they recognize foreign antigens and destroy them through phagocytosis (often the first to respond)
what is the function of monocytes/macrophages?
they engulf foreign antigens and cell debris and process antigen and present it
what is the function of B-lymphocytes?
they are independently able to identify foreign antigens and differentiate into antibody producing plasma and memory cells.
Which LN drains the head and neck?
cervical LNs
Which LN drains the upper limb, breast, and skin above the umbilicus?
Axillary LNs
What drains (lymph) the right side of the body above the diaphragm?
Right lymphatic duct
What drains the rest of the lymph into the junction of the left subclavian and internal jugular veins?
thoracic duct
What is the function of the natural killer cells?
Use perforin and granzymes to induce apoptosis of virally infected cells and tumor cells. Induced by non-specific activation (MHC 1). Also only lymphocyte member of the innate immune system.
what is the role of macrophages in the spleen?
they remove encapsulated bacteria
What is the consequence of splenic dysfunction? (post-splenectomy or sickle cell disease)
dec IgM –> dec complement activation –> increased susceptibility to encapsulated organisms.
what do we see (histo) post splenectomy?
howell-jolly bodies, target cell, thrombocytosis
which encapsulated organisms are we worried about with a damaged spleen?
Strep pneumoniae, H. influenzae type B, Neisseria meningitis, E.coli, Salmonella, klebsiella, and group B strep
where are B and T cell made?
bone marrow
Where do T cell mature?
Thymus = site of T-cell differentiation and maturation.
what are the components of adaptive immunity?
T cell, B cell, and circulating antibodies
what are the components of innate immunity?
neutrophils, macrophages, monocytes, dendritic cells, NK cells (lymphoid origin), and complement
What type of response do we see in innate immunity?
non-specific
what type of response do we see in adaptive immunity
highly specific, refined overtime– memory response becomes faster and more robust.
What proteins are secreted in innate immunity?
lysozyme, complement, CRP, defensins, etc.
What proteins are secreted in adaptive immunity?
immunoglobulins
what is the key feature of pathogen recognition in innate immunity?
Toll-like receptors (TLRs): pattern recognition receptors that recognize pathogen associated molecular patterns.
what is the key feature of pathogen recognition in adaptive immunity?
memory cells: activated B and T cells
where is MHC class 1 expressed?
expressed on all nucleated cells (not on RBCs)
where is MHC class 2 expressed?
only on antigen presenting cell: dendritic cells, macrophages, and B-cells (plasma cells)
what is the function of MHC class 1?
to present endogenously synthesized antigens (e.g viral) to CD8+ cytotoxic T cells.
what is the function of MHC class 2?
to present exogenously synthesized proteins (e.g. bacterial proteins, viral capsid proteins) to T-Helper cells.
what diseases are associated with HLA B27?
PAIR: Psoriatic arthritis, Ankylosing spondylitis, arthritis of Inflammatory bowel disease, Reactive arthritis
what disease is associated with HLA DQ2/DQ8?
celiacs dz
what disease is associated with HLA DR4?
Rheumatoid arthritis, and type 1 diabetes
what is the principle immunoglobulin in exocrine secretions e.g. breast milk, respiratory and intestinal mucosa, saliva, and tears?
IgA
what immunoglobulin can move across the placenta thus becoming important for newborn’s immunity?
IgG
what is the main immunogloblin in the serum?
IgG
what immunoglobulin activates complement and is important for opsonization?
IgG
what immunoglobulin attaches to mast cells in the respiratory system and intestinal tract and plays an important role in allergic response?
IgE
what immunoglobulin is the first to form in response to an attack?
IgM
what immunoglobulin controls the A, B, and O blood group antibody responses?
IgM
Antigens present on all nucleated cell in the body that identify a cell as self are called what?
HLA
what is a hapten?
a substance that normally does not act as an antigen- can elicit an immune response when attached to a larger protein but not alone.
complement is activated in what type of immune response?
B-cell mediated immune response
what types of proteins are involved in vasodilation, chemotaxis, opsonization of antigens, lysis of cells and blood cloting?
complement
what is opsonization?
a coat (marker) is placed on cells that they can recognize for easier removal.
what role does interferon play?
they are released when invading organism is a virus. they inhibit production of virus in infected cells, prevent viral spread, enhance activity of macrophages, NK cell, cytotoxic T cells and inhibit growth of tumor cells.
which cytokine permits cells of the immune system to “talk” to one another and initiate a response?
IL-1
which cytokine promotes humoral immunity?
IL-4, 5, and 10.
which cytokine promotes cellular immunity?
IL-2, stimulates T-cells.
hayfever is what type of hypersensitivity?
Type 1
IgE is formed in what type of hypersensitivity?
type 1
antibodies are produce in what type of immunity?
humoral
The reaction of antigens and antibodies at cell surface is what type of hypersensitivity reaction?
type 2
anaphylactic and atopic reactions are what type of hypersensitivity?
type 1
Reaction to blood transfusion would be what type of hypersensitivity reaction?
type 2
The reaction of antigen and antibody in extracellular fluid space is what type of hypersensitivity reaction? (immune complex)
type 3
Serum sickness is an example of what type of hypersensitivity reaction
type 3
A cell mediated reaction or delayed reaction mediated by T lymphocytes and antigen is an example of what type of hypersensitivity?
type 4
TB is an example of what type of hypersensitivity?
type 4
loss of normal tolerance by the immune system of “self” antigen on the surface of cells with destruction of normal tissue with auto-antibodies is defined as what?
autoimmunity
what is the name for genital warts?
condyloma cuminata
Downey cells or atypical lymphocytes are seen in what infection?
Epstein Barr (EBV)
why does hep B have a potential carrier state?
viral DNA is integrated into the chromosome of the host cell
pandemics of flu are associated with what?
antigenic shift, major changes in RNA
which polio vaccine is alive attenuated and given orally?
Sabin
Which polio vaccine is inactivated multi-valent and injectable?
salk
how does polio cause paralysis?
by destroying motor neuron of the anterior horn and medulla
hemolytic anemia, pernicious anemia, and good pastures syndrome are examples of what type of HS reaction?
type 2
SLE, post-strep GN, and serum sickness are what type of HS reaction?
type 3
MS, guillian barre, and TB are examples of what type of HS reaction?
type 4
what antibody is found in myasthenia gravis?
anti-ACh receptor
what antibody is found in good pastures syndrome?
anti-basement membrane (Lungs and kidneys)
what antibody is found in SLE?
anti-dsDNA, anti-smith
what antibodies are associated with PM and DM?
anti-Jo, anti-SRP, and anti-Mi-2
what antibodies are found in hashimotos thyroiditis?
anti-microsomal (TPO), and anti-thyroglobulin (TG)
anti-CCP is related to?
Rheumatoid arthritis
what antibodies are seen in RA?
RF and anti-CCP
anti-TSH receptor is seen in what disease?
Graves disease
Celiac disease has what antibodies?
IgA anti-tissue transglutaminase (TTG)
c-ANCA is seen in what disease?
Wegner’s: granulomatosis with polyangiitis
what is the role of IgE?
binds mast cells and basophils, crosslinks when exposed to allergen, mediating a type 1 HS reaction through release of inflam mediators such as histamine.
which immunoglobulin has the lowest concentration in serum?
IgE
what is the role of IgA?
prevents attachment of bacteria and viruses to mucous membranes. It does NOT fix complement. It is the most produced antibody overall but secreted in tears, saliva, mucous and early breast milk (not serum)
what are acute phase reactants?
factors whose serum concentration change significantly in response to inflammation; produced by the liver in both acute and chronic inflam states. Induced by IL-6, IL-1, TNF-alpha, and IFN-gamma.
role of ferritin as an acute phase reactant?
upregulated: bind and sequesters iron to inhibit microbial iron scavenging.
role of CRP as an acute phase reactant?
upregulated: opsonin; fixes complement and facilitates phagocytosis. measured clinically as an ongoing sign of inflammation.
role of albumin as an acute phase reactant?
downregulated: reduction conserves amino acids for positive reactants.
role of transferrin as an acute phase reactant?
down regulated: internalized by macrophages to sequester iron.
how many signals are required for T-cell activation, B cell activation, and class switching?
two
role of IL-1?
an endogenous pyrogen: osteoclast activating factor. Causes fever and acute inflammation.
role of IL-6?
secreted by Th2 cells, causes fever and stimulates the production of acute phase proteins.
role of IL-8?
major chemotactic factor for neutrophils- signals neutrophils to be recruited to clear infections.
role of IL-12?
induces differentiation of T- cells into Th1 cells. Activates NK cells. Also secreted by B-cells.
TNF-alpha?
mediates septic shock. Activates endothelium. causes leukocytes recruitment, vascular leak
