Immunopathology II

Question 1

Tolerance

Answer 1

incapability to mount an immune response against specific antigen

Question 2

self tolerance

Answer 2

lack of responsiveness to self antigens

Question 3

Central tolerance

Answer 3

referes to deletion of self-reactive B and T cells during their maturation inthe bone marrow and thymus

Question 4

Peripheral tolerance

Answer 4

mechanism to eliminate self reactive T cells that escaped intrathymic delection (- selection)

• anergy
• suppression by reg. t cells
• deletion by induced apoptosis
• antigen sequestration

Question 5

Anergy

Answer 5

T cell rendered useless after bad enconter

T cell requires two signals: MHCII and B7 (APCs)

• secondary signal B7–>CD28 is absent
• instead CTLA4 binds B7–>thus anergy

Question 6

Suppression by regulatory T cells (T-regs)

Answer 6

• T-regs develop in the thymus and express CD4 and CD25
• mutation in Fox3, required for their dev and fx results in severe autoimmune

Question 7

Deletion by Induced apoptosis

Answer 7

involves fas ligand system

mutaions can lead to autoimmune lyphoproliferative syndrome

Question 8

antigen sequestration

Answer 8

some antigens are hidden from immune system due to lack of communication with blood and lymph (immune-privileged sites such as testis, eye, brain

Question 9

Systemic Lupus Ertyhematosis (SLE)

Answer 9

unknown cause, but fundamental defect is failure to maintain self-tolerance

-characterized by presence of antinuclear antibodies

Question 10

Criteria for diagnosis

Answer 10

Question 11

Antinuclear antibodies (ANA)

Answer 11

Question 12

Antinuclear Antibodies and Autoimmune Disease

Answer 12

Drug induced Lupus will have antihistones.

Question 13

Antiphospholid antibody (lupus anticoagulat) is associated with?

Answer 13

thrombosis and recurrent miscarriages

Question 14

Early complement deficiency (C3, C4, C1q) in SLE will?

Answer 14

impair removal by MO and favor tissue deposition

approx 5-10% patients

Question 15

How are vesceral lesions mediated in SLE?

Answer 15

Hypersensitivity type III

Question 16

What happens when cel nuclei are exposed to ANA in SLE?

Answer 16

cell damage occurs. those cells lose their chromatin pattern and become homogenous (hematoxylin bodies)

Question 17

What does this figure represent?

Answer 17

Hematoxylin Bodies (SLE)

Question 18

What does this figure represent?

Answer 18

Immune-complex deposition (Type III HS)

SLE

Question 19

Class I of Lupus Nephritis:

Answer 19

Question 20

Class II of Lupus Nephritis:

Answer 20

Mesangial Glomerulonephritis (20%), mild symptoms

Question 21

Class III of Lupus Nephritis:

Answer 21

Focal prliferative (25%), moderate disease

Question 22

Class IV of Lupus Nephritis:

Answer 22

Diffuse proliferative (50%) most severe, characterized by wire loops

* active disease*

Question 23

Class V of Lupus Nephritis:

Answer 23

Membranous (15%), capillary wall thickening, nephrotic syndrome

Question 24

Answer 24

Normal Glomerulus (Class I)

Question 25

Answer 25

Class II Glomerulonephritis

Question 26

Answer 26

Class III Focal Proliferative glomerulonephritis

Question 27

Answer 27

Class IV Diffuse proliferative glomerulonephritis \*most active form

Question 28

Answer 28

Class IV "Wire loep"

Question 29

Answer 29

Class V: membranous glomerulonephritis

Question 30

Sjogrens Syndrome

Answer 30

Autiunnybe destruction of Lacrimal and salivary glands - dry eyes, dry mouth - about 75% patients have RA factors - 50-80% have +ANA - \>90% antibodies against SS-A & SS-B present - 40x risk increase for non-Hodgkin's lymphoma - women age 50

Question 31

What are these characteristic of?

Answer 31

Sjogens disease

Question 32

Systemic Sclerosisi (Scleroderma)

Answer 32

- chronic disorder, abnormal accumulation fo firbous tissue in skin and other organs - common in 50-60yo F - diffuse and limited variants - Associated w/ anti-DNA topoisomerase 1 and anticentrome antiboides - diffuse variant: skin(most), GI (90%), lungs (50%), kidneys (65%) and SK (common)

Question 33

What autoimmune disorder is represented here?

Answer 33

Scleroderma A. normal B. fibroblasts, cell mediated process w/ lymphocytes

Question 34

What characteristic of limted type scleroderma does this figure show?

Answer 34

Calcinosis of soft tissues?

Question 35

What type of limited scleroderma does this figure represent?

Answer 35

Esophageal invovement-fibrosis of the lower 2/3 esophagus

Question 36

Rheumatoid arthritis

Answer 36

autoimmune disorder leads to chronic systemic inflammation affecting many tissue - arthritis- affects small joints of hand & feet and is non-suppurative that eventually leads to destruction of jts. - extra articular symptoms are fairly common and vascular/renal finding similar to SLE - incidence 1:100, F:M 3-5:1, 2nd-4th decades of life

Question 37

Rheumatoid factor

Answer 37

IgM attack B cell producing IgG found in 80% believed to be involved in extra articular pathology (due to similarities w/ SLE)

Question 38

What does this figure show?

Answer 38

ulnar deviation in arthritis

Question 39

What does this figure show?

Answer 39

Athritis: PIP joints (Swan neck deformity)

Question 40

What does this figure show?

Answer 40

Arthritis ## Footnote Pannus formation – mass of inflammatory cells that begins destroying cartilage (B, T, Plasma cells)

Question 41

What does this figure show?

Answer 41

1. Normal Synovium 2. RA synovium

Question 42

What does this figure show?

Answer 42

Rheumatoid nodules- central zone of necrosis surrounded by epithelioid histiocytes

Question 43

What does this figure show?

Answer 43

Libman-Sacks Endocarditis - caused by lupus aswell - inflammatio and pus affecting valves

Question 44

Autoimmune disease and HLA

Answer 44

SLE--\>HLA-DQ RA--\>HLA-DR4 JUVENILE RA--\>HLA-B27 \*SPONDYLOARTHROPATHIES--\>HLA-B27 SJOGRENS SYNDROME--\>HLA-DR3

Question 45

Seronegative Spondyloarthropathies

Answer 45

heterogenous group - characterized by - do not see RA factor (this is in RA) - pathological changes to ligaments - involvement of sacroiliac joints - association w/ HLA-B27

Question 46

What does this figure represent?

Answer 46

Ankylosing spondylitis: sacro-iliac involvement -common in males