Dr. Vishy - Immune Skin Conditions Flashcards
Skin Layers Mnemonic (top to bottom):
- Californians
- Like
- Girls (in)
- String
- Bikinis
Stratum Corneum, Lucidum, Granulosum, Spinosum, Basalis
Glycoprotein desmosome glue
Desmogleins (1 and 3)
Superficial desmoglein
Desmoglein 1
*the other one’s the other one
Proteins in hemidesmosomes
Bullous pemphigoid antigen (BPA1&2)
Connects keratinocytes of stratum basale to basement membrane
Hemidesmosomes
Dendritic cells in dermis is called
Dermal DCs
*DC = dendritic cell
DC in epidermis is called
Langerhans cell
molecular wt for BPAg1
230
molecular wt for BPAg2
180
Important protein for keeping epidermal skin barrier intact. Also helps terminal differentiation of epidermis.
Filaggrin
EXTRAcellular antigens are conjugated to which major histocompatibility class within dendritic cells?
MHC ClassII
Antigens broken down by proteosomes are attached to which intracellular protein on its way to the endoplasmic reticulum?
TAP proteins
Within the endoplasmic reticulum, viral antigens are attached to MHC class I and the entire complex is then presented to
CD8 (cytotoxic Tcells)
Which signal pushes Tcells to become effector cells?
Signal 2
Mutation of this protein can leave epidermis susceptible to infection
Filaggrin
Homeostasis mechanism to “turn off Tcells”
CD 80/86 of APC bound to CTLA4 of Tcell
During antigen recognition, IL-12 pushes Tcells to become
TH1 subset
These T helper cells do the following
- Aid in cell immunity
- Secrete IL-2 and IFN-gamma
Th1
These T helper cells do the following
- Aid B cells to produce Abs
- Secrete IL-4, IL-5, and IL-10
Th2
During antigen recognition, IL-10 pushes Tcells to become
TH2 subset
Which signal involves “polarizing cytokines” during antigen recognition?
Signal 3
*cytokines push Tcells to TH1 or TH2
Released by Cytotoxic T lymphocytes and generates transmembrane pores in target cells
Perforins
Released by CTLs and induce apoptosis inside cytosol of target cells
Granzymes
Apoptotic signal of membrane bound molecule of target cells
Fas
This ligand is on CTL cell surface and binds Fas on target cells
Fas ligand
Inflammatory DCs
- very good at migration
- very good at antigen presenting
IDECs
DCs that present Type I interferons
Plasmacytoid DCs
Type I interferons
Interferon alpha
Interferon beta
These interferons protect against viral infection
Type I interferons
alpha, beta
These are like basophils, but are present in DERMIS and cross link with IgE
Mast cells
- have Fc epsilon Receptors for IgE
Name the Hypersensitivity Type:
Immediate/Anaphylactic
- IgE
- allergy
- Mast cells/ Basophils
Type I
*seconds-mins
Name the Hypersensitivity Type:
-Immune Complex mediated
Type III
Delayed-Type Hypersensitivity
Type IV
Which Hypersensitivity is antibody-mediated cytotoxic?
Type II
Hypersensitivity reaction involving IgM and IgG, resulting in complement activation and cell rupture
Type II
Basophils are like mast cells and travel in the
Blood
Hypersensitivity Reaction in which Abs bind to soluble antigen and forming immune complexes
Type III
Urticaria has pale center and raised red edges caused by histamine release. Which Hypersensitivity reaction is urticaria?
Type I
Type I Hypersensitivity reaction involving defective FILAGGRIN
Atopic dermatitis
With atopic dermatitis, which stage involves INF gamma and viral infection?
Chronic
During the chronic stage of atopic dermatitis, what DC type is low, leading to susceptibility to viral infection?
Plasmacytoid DCs
With atopic dermatitis, which stage involves rashes and bacterial infection?
Acute
During chronic atopic dermatitis which interferon is present and which Tcell subset is dominant?
IL-10 and TH2
T cell homing antigen important during atopic dermatitis
(CLA) Cutaneous lymphocyte associated antigen
Which hypersensitivity?
- GOODPASTURE’s
- Pemphigus foliaceus
- Bullous pemphigoid
- Linear IgA Dz
Type II
During acute atopic dermatitis, which interferon is present ad which Tcell subset is dominant?
IL-12 and TH1
- IgG
- Autoantibody
- Desmoglein 3
- Ashkenazi Jews
Pemphigus vulgaris
Deeper Desmoglein
3
Deep blisters in skin and mouth
Pemphigus vulgaris
-can cause death
- Looks worse than pemphigus vulgaris, but it’s not
- IgG
- Autoantibody
- Desmoglein 1
Pemphigus foliaceus
- Auto antibodies to BPAg1 & 2
- IgG
- No acantholysis
Bullous Pemphigoid
Acantholysis
Pemphigus vulgaris
Desmoglein 1 and NO ACANTHOLYSIS
Pemphigus foliaceus
Autoantibodies from IgA class specific to BPAg2
Linear Immunoglobulin A Disease
- IgA
- HLA: A1, B8, DR3, DQ2
- Gluten
Dermatitis herpetiformis
*IgA
Which Hypersensitivity type?
Dermatitis herpetiformis and SLE
Type III
Garbage DNA and histones trigger which Disease?
SLE
15mm TB induration
low risk individuals
10 mm TB induration
risk groups and researchers
5 mm TB induration
HIV
What type of hypersensitivity is contact dermatitis?
Type IV
These skin conditions caused by which hypersensitivity reaction?
- Erythema multiform minor and major
- Steven-Johnson
- Toxic epidermal necrolysis
Type IV
Rashes on the extremities caused by autoimmune attack of keratinocytes by CD8+
-mycoplasma or HSV
Erythema multiform minor
Rashes on the extremities caused by autoimmune attack of keratinocytes and effecting mucous membranes
Erythema multiform major
Blisters on less than 10% of body surface
-usually trunk, mucosa
Steven-Johnson Syndrome
Life threatening blisters on more than 10% body surface. Hospitalized like burn victim
Toxic epidermal necrolysis
- Scleroderma
- Psoriasis
Autoimmune skin diseases
Systemic proliferation of fibroblasts
Scleroderma
Hyper proliferation of keratinocytes
Psoriasis
Collagen in the blood vessels causing red, white, blue fingertips
Scleroderma
Fibrosis in GI tract = peritonitis
Fibrosis at heart = pericarditis
Fibrosis in lungs
Scleroderma
Over activation of Tcell subtypes in skin by either
- superantigens OR
- lack of CTLA-4 (Tcell brakes)
Psoriasis
Which skin dz has biphasic Tcell responses during acute and chronic stages?
Atopic dermatitis
60y/o male complains of hemoptysis and hematuria. Lab test confirm presence of antibodies against glomerular basement membrane protein. What’s his disease?
Goodpasture’s
Which one is Type I?
a. Pemphigus vulgaris
b. Pemphigus foliaceus
c. Goodpasture’s
d. Dermatitis herpetiformis
e. Atopic dermatitis
Atopic dermatitis
A person has blisters all over body and tests positive for desmoglein 1 autoantibodies. What’s his disease?
Pemphigus foliaceus