Immunology Flashcards
what are lymph nodes?
1) Act with filtration of B or T cells
What are the parts of the lymph node, and what is the use?
1) Follicule: B cell localization
2) Medulla: Drain lymphatics and contain reticular cells
3) Paracortex:houses T cells ( not well developped in DiGeorge syndrome)
Which part of the body do the following lymph nodes drain? Cervical Hilar Mediastinal Axillary Celiac Superior mesenteric Inferior mesenteric Internal iliac Para-aortic Superficial inguinal Popliteal.
1) Cervical (head and neck)
2) Hilar (lungs)
3) Mediastinal (Trachea and esophagus)
4) Axillary: Upper limb, breast, skin, ombilical
5) Celiac: liver, stomach, spleen, pancrease
6) Superior mesenteric: lower duodenum, jejunum, ileum, colon to splenic flexure
7) Inferior mesenteric: colon from splenic flexure to upper rectum
8) Internal iliac: lower rectum to anal canal, vagina, cervix, prostate
9) Para-aortic: testes, ovaries, kidnies, uterus
10) Superficial inguinal: anal canal, skin below ombilicus, scrotum,vulva
11) Popliteal: dorsolateral foot, posterior calf
where are T cells found within the spleen?
1) Periarteriolar lymphatic sheath
Where are B cells found?
In the follicles in the white pulp
What is found in the marginal zones between the red pulp and the white pulp?
Macrophages
Specailized B cells
Antigen presenting cells
What is seen in blood smear after a splenectomy?
1) Howell-Jolly bodies (nuclear remnants)
2) Target Cells
3) Thrombocytosis: loss of sequestration and removal
4) Lymphocytosis: loss of sequestation
What is the thymus used for?
What are changes to thymus depending on the condition?
1) Site of T Cell differentiation and maturation
2) Hypoplastic with DiGeorge’s syndrome
3) Enlarged if have myasthenia gravis.
What are components of inate vs adaptive immunity?
1) Inate have neutrophils, macrophages, and noncytes
2) Adpative have: T cells, B cells and antibodies
What is the resistance between inate and adaptive immunity?
1) Inate: perists through generations, and does not change within an organismes lifetime
2) Microbial resistance, not heritable
Response to pathogents (inante vs adaptive)
1) Inate: rapid
2) Adpative: highly specific, and refined over time, the memory response is faster
What are proteins associated with the rapid/inate?
1) Inate: C-reative protein
2) Adaptive: immunoglobulins
How does recognition occur? (Innate vs adaptive)
1) Inate: Tollike recpetors
2) Pattern recognition receptors (LPS for gram - bacteria)
3) Adpative: Memory activated B and T cells.
MHC 1 vs MHC 2 in terms of loci?
HLA-A, HLA-B, HLA-C (1 letter)
MHC-2 (HLA-DP, HLA-DQ, HLA-DR) (has 2 letters)
MHC 1 vs MHC 2, binding?
1) TCR and CD8 (MHC 1)
2) TCR and CD4 (MHC 2)
MHC 1 vs MHC 2 expression?
1) MHC1: on all nucleated cells (but not RBC)
2) MHC 2: On all APC
Function of MCH 1 vs MHC 2?
MHC 1: endogenously synthesized antigens
MHC 2: Presents exogensously sythesized antigens
What are associated proteins with MHC 1 and MHC 2?
B2-microglobulin
Invariant chain
What are HLA subtypes associated with disease? Hemochromatosis B8 B27 DQ2/DQ8 DR2 DR3 DR4 DR5
A3: Hemochromatosis
B8: Addison diseasse, mysanthia gravis
B27: PSoratic arthritis, ankylosing spondylitis
DQ2/DQ8: Celiac disease
DR2: Multiple scleosis
DR4: Rheumatoid arthritis. DM
DR5: pernicious anemia (Hashimoto thyroiditis)
What do natural killer cells do?
1) Use perforin and granzymes to induce apoptosis of infected cells and tumor cells
2) Activity enhanced by IL 2, Il-12, IFN- alpha
What are the positive and negative selection of T cells?
Positive selection: Thymic cortex, capable of binding to self MHC are allowed to survive
Negative selection: Thymic medulla. T cells with high affinity for self antigens undergo apoptosis.
What do helper T cells do?
1) TH 1 cell Secrete IFN-Gamma that activate the macs and cytotoxic T cells.
2) Th2 cells: Il-4 and IL-5 (recruits eospinophils for parasitic defense and promote IgE
What is naive T-Cell activation?
Dendritic cells do the recognizing
1) Presented to MHC II (either CD4+ or CD8+)
2) Proliferation and survival
3) Cell activates cytokines and kills virus infected cells
What is B cell activation class, switching?
1) B cell receptor mediated endocytosis (presented on MHC II)
2) Cell secretes cytokines that Ig Class switch of B cell, and activates the antibody production.
What are the structures of antibody Fab, and the Fc?
1) FaB: fragment antigen binding (determines idiotype), only 1 antigenic specificity per B cell
2) Fc (Constant): Carboxyl terminal
How is generation of antibody diversity accomplished?
1) Recombination of light and heavy chains
2) Random addition of nucleotides in the chains
3) Recombination of light and heavy chain genes
What immunoglobulin isotypes?
1) IgG: delayed response to bacterial toxins and viruses
2) IgA: prevents attachements of bacteria and virus to mucous membrane (secretory)
3) IgM: intermediate response to antigen
4) IgD: Unclear
5) IgE: immnuity to worms by activating eosinophils.
What are the thymus-independent antigens?
1) Weakly immunogenic (requires boosters)
2) Thymus dependent: Contain diphtheria vaccins (immnuological memory occur as a result of direct contact with B cells and Th-Cells
What are acute phase reactants?
Factors whose serum concentration change significantly in response to inflammation (notably IL-6)
C-reative protein Ferritin Fibrinogen Hepcidin Serum Amyloid A
What are negative (downregulated) during stress?
1) Albumin
2) Transferrin
What does C-reactive protein measure?
Facilitates phagocytosis, sign of ongoing inflammation
What does ferritin measure?
Binds and sequesters iron to inhibit microbial iron scavenging
What does fibrinogen measure?
1) Coagulation factor, promotes endothelial repair (goes with ESR)
What does Hepcidin show?
1) Decrease iron absorption, and decrease iron release
What does serum amyloid A show?
1) Prolonged elevation can lead to amyloidosis
What does transferrin show?
Internalized by macrophages to sequester
Which organ produces the complement system?
Hepatically synthesized plasma proteins that defend against gram - bacteria
How is the complement system mediated?
By IgG of IgM
What are the functions of complement pathway?
C3b opsonization
C3a, C4a, C5a anaphylaxis
C5: neutrophil chemotaxis.
Disorder associated with C1 esterase inhibitor deficiency?
1) Angioedmea (unregulated kallikrein, increased bradykinin)
Disorder associated with C3 deficiency?
Recurrent sinus and respiratory infection
Disroder associated with C5-C9 deficiency?
Increased susceptibility to Neisseria bacteremia
Disorder associated with DAF (GP1-anchored enzyme deficiency)?
Complement mediated lysis of RBC
Passive vs active immunity due to acquisition?
1) Receiving preformed antibodies vs exposure to foreign antigens
Passivevs active immunity due to onset?
Passive is rapid, and active is long lasting protection with memory
Passive vs active immunity duration?
Passive: short life span
Active: long lasting (protection)
Examples of passive vs active immunity?
IgA in breast milk
IgG crossing placenta
Active: natural infection
What are some examples of passive immunity vaccines?
1) Tetanus
2) Botulism
3) HBV
4) Varicella
5) Rabies
When there is exposure to one of these entities, then the vaccine is given, and because works rapidly, can heal.
Which response is activated by the live attenuated vaccine?
Cellular and humoral response
what are the pros and cons of live attenuated vaccine?
1) Induces lifelong immunity
2) cons: may revert to virulent form *cannot be given if immunocrompromised, or pregnent
What are some examples of live attenuated virus?
1) Influenzae
2) Measels
3) BCG
4) Polio (sabine)
5) Varicella
6) yellow fever
What are pros and cons of inactivated or killed vaccine?
Pro: safer then live vaccine
Cons: weaker, immune response, and needs a booster
What are the 5 types of hypersensitivity reactions?
1) Type 1 (anaphylactic and free antigen crosslinked IgE
(rapid reaction, because has preformed antibodies)
Test with IgE
2) Type 2 Cytotoxic (direct and indirect coombs test)
Direct: detects antibodies bound to patient’s RBC
Indirect: detects serum antibodies
IgM and IgG
3) Type 3: immune complex immune complex-antigen/antibody, its IgG
(Vasculitis or systemic manifestations)
Examples: SLE, polyarertis nodosa, post streptococcal glomerulonephrtis
4) Type 4:Sensitized T cells encounter antigen and the release cytokines (lead to macrophage activation)
Usually this is delayed or last cell mediated, and not transferred by serum.
Examples: Contact dermatitis
Graft vs host disease
Multiple sclerosis
What is serum sickness?
Immune complex disease in which antibodies to foreign proteins are produced
might be deposited on membrane and can fix tissue
Can lead to arthus reaction
What are the causes if serum sickness?
Drugs acting as haptens
What are the symptoms of serum sickness?
1) Fever
2) Urticaria
3) Arthralgia
4) Proteunuria
5) Lymphadenopathy (5-10 days) after antigen exposure
What is Arthrus reaction?
1) Antibody medited hypersensitivity reaction
2) Intradermal injection of antigen into pre-senstized skin
3) Have immune complex on the skin leading to edema, necrosis, and activation of the complement
What are possible types of blood transfusion reactions?
1) Allergic Reaction
2) Anaphylactic reaction
3) Febrile nonhemolytic transfusion reaction
4) Acute hemolytic transfusion reaction
What is presentation and cause of allergic reaction to blood?
1) Hypersensitivity to plasma proteins: urticaria, pruritis, wheezing, fever
Presentation and cause of anaphylactic reaction?
IgA deficient individual
Needs to recieve blood products without IgA
Dyspnea, brochospasm, hypotension
Treatment: epinephrine
Presentation and cause of febrile, non hemolytic transfusion reaction?
Type 2 hypersensitivty reaction
Host antibodies against donor HLA
Fever
Headaches
Chills
Flushing
Causes and presentation of acute hemolytic transfusion reaction?
Type II reaction
Intravascular hemolysis
ABO incompatibility
Fever Hypotension Tachycardia Flank pain Hemoglobinuria Jaunedice
Autoantibody with anti-ach?
Mysanthia gravis