Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Dermatology > Immunology > Flashcards

Immunology Flashcards

(68 cards)

Start Studying
1
Q

how is the keratin layer formed?

A

through terminal differentiation of keratinocytes to corneocytes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

name some important structural proteins in the keratin layer & epidermis

A

filaggrin
involucrin
keratin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

name some features of the keratin layer

A

tough
lipid rich
physical barrier

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what do keratinocytes do in the epidermis?

A

sense pathogens via cell surface receptors and help mediate an immune response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what can keratinocytes be activated in the epidermis?

A

UV light

sensitzers e.g. allergic contact dermatitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what do keratinocytes produce in response to pathogens?

A

antimicrobial peptides (AMPs)
cytokines
chemokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are Langerhans cells?

A

a type of dendritic cell that intersperse with keratinocytes in the epidermis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what are Langerhans cells characterised by?

A

the birbeck granule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what do Langerhans cells do?

A

process lipid Ag & microbial fragments & present them to effector T cells to activate them

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what type of T cells are found in the skin?

A

mainly CD8+ in the epidermis
CD4+ & CD8+ in the dermis
subsets (NK cells) are also found

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

which CD4+ Th cells are associate with inflammation?

A

Th1 - psoriasis
Th2 - atopic dermatitis
Th17 - atopic dermatitis & psoraisis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

where are T cells produced?

A

bone marrow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

where are T cells sensitised?

A

thymus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

how are Ags recognised and T cells activated?

A

using the T cell receptor (TCr) & major histocompatibility complex (MHC)
enhanced by co-recptors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what do Th1 cells do?

A

activate macrophges to destroy macrophages using IL2 & IFN gamma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

when are Th1 cells especially useful?

A

against viral invaders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what do Th2 cells to?

A

help B cells to make Ab using IL4, IL5 & IL6

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

when are Th2 cells especially useful?

A

against parasitic invaders

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

when are CD8+ cells useful?

A

important in the protection against viruses & cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

which types of dendritic cell are found in the dermis?

A

dermal dendritic cell & plasmacytoid dendritic cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what do dermal DCs do?

A

involved in Ag presenting & secreting cytokines & chemokines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what do plasmacytoid DCs do?

A

produce IFN alpha

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

when are plasmacytoid DCs found in the skin?

A

they are low or absent in normal skin but found in relatively high numbers in diseased skin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is psoriasis?

A

an over-reaction of the immune response presenting as chronic inflammation, specifically a non-late phase wound response

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
describe the immunopathogeneis of psorasis
keratinocytes under stress release factors that stimulate pDC to produce IFN alpha, interleukins& TNF which activate DC which migrate to lymph nodes to present to & activate Th cells T cells then attracted to dermis by cheekiness & secrete interleukins
26
what is the key factor in atopic eczema?
impairment of the skin barrier function due to mutations in the filaggrin gene and decreased AMP in skin
27
how does impairment of the skin barrier function cause atopic eczema?
allows access/sensitisation to allergen & promotes colonisation by micro-organisms
28
what does filaggrin do in normal skin?
normally found in granules in granular layer where it breaks down & binds water helping the skin to retain water, naturally moisturising the skin
29
which interleukin is clinically relevant in eczema?
IL4
30
what happens in vitiligo?
melanocytes are attacked by T lymphocytes
31
what happens in SLE?
auto-antibodies are produced by B lymphocytes
32
when are Type II hypersensitivity mechanisms important?
in autoimmunity & transplantation | mediated by IgG & IgM
33
when are type III hypersensitivity mechanisms important?
in certain drug reactions | mediated by IgG & IgM
34
when are type i hypersensitivity mechanisms important?
in allergies | mediated by IgE
35
when are type IV hypersensitivity mechanisms important?
in contact allergies & tuberculin reaction | mediated by Th1 cells
36
which factors affect skin immune response in organ transplant?
immunosuppression - after 10 years most probable cause of death is skin cancer as its more like to metastasis due to lack of active immune surveillance
37
which factors affect skin immune response to UV light?
immunosuppression & structure
38
which factors affect skin immune response in ageing?
changes in skin structure decreased ability to detect maligned cells decreased ability to detect Ag decreased ability to distinguish self cells from non-self
39
what 2 types of drug reactions are there?
immunologically mediated reactions & non-immunologically mediated reactions
40
what types of immunologically mediated drug reactions are there?
type 1 - anaphylactic type 2 - cytotoxic reactions type 3 - immune complex-mediated reactions type 4 - cell mediated delayed hypersensitivity reactions
41
are immunologically mediated drug reactions does dependant?
no
42
what non-immunologically mediated drug reactions are there?
``` eczema drug induced alopecia phototoxicity skin erosion/atrophy from topical therapy psoraisis pigmentation ```
43
are non-immunologically mediated drug reactions does dependant?
can be
44
who do drug reactions present?
``` exanthematous/morbiliform/maculopapular urticarial papulosquamous/pustular/bullous pigmentation itch/pain photosensitivity ```
45
what are the risk factors for developing a drug eruption?
``` age - young adults > infants/elderly gender - females > males genetics concomitant disease immune status chemistry route does kinetics/half-life ```
46
what are exanthematous drug eruptions?
Most common type of drug eruption (90%). | Idiosyncratic, T-cell mediated delayed type hypersensitivity (Type IV) reaction,
47
describe some of the clinical features of an exanthematous drug eruption
usually mild & self-limiting widespread symmetrically distributed rash sparing the mucous membranes pruritus & mild fever is commone
48
what are the indicators of a potential severe reaction in exanthematous drug eruptions?
``` Involvement of mucous membrane and face. Facial oedema & erythema. Widespread confluent erythema. Fever (>38.5⁰C). Blisters, purpura, necrosis. Lymphadenopathy, arthalgia. Shortness of breath, wheezing. ```
49
name some drugs associated with exanthematous drug eruptions (at least 4)
``` Penicillins Sulphonamide antibiotics Erythromycin Streptomycin Allopurinol Anti-epileptics: carbamazepine NSAIDs Phenytoin Chloramphenicol ```
50
what is the mechanism of urticarial drug reactions?
IgE mediated hypersensitivty reaction after rechallenge with drug or direct release of inflammatory mediators from mast cells on first exposure
51
give 2 examples of pustular/bullous drug eruptions
acne | acute generalised exanthematous pustulosis (AGEP)
52
what do fixed drug eruptions look like?
well demarcated round/ovoid plaques
53
what do fixed drug eruptions feel like?
red & painful
54
where are fixed drug eruptions found?
hands, genitalia, lips & occasionally oral mucosa
55
how do fixed drug eruptions resolve?
with persistent pigmentation when the drug is stopped
56
can fixed drug eruptions re-occur?
yes, on the same site on re-exposure to the drug
57
how fixed drug eruptions present?
as eczematous lesions, papules, vesicles or urticaria
58
which drugs are associated with fixed drug eruptions?
tetracylcine, doxycycline, paracetamol, NSAIDs, carbamazepine
59
what do combined cutaneous and systemic symptoms include in severe cutaneous adverse reactions?
stevens-johnson sydrome toxice epidermal necrolysis drug reaction with eosinophilia & systemic symptoms acute generalised exanthematous pustulosis
60
what is stevens-johnson syndrome (SJS)?
a form of toxic epidermal necrolysis, is a life-threatening skin condition, in which cell death causes the epidermis to separate from the dermis
61
what is toxic epidermal necrolysis (TEN)?
also known as Lyell's syndrome, is a rare, life-threatening skin condition that is usually caused by a reaction to drugs
62
what is drug reaction with eosinophilia& systemic symptoms (DRESS)?
a severe idiosyncratic drug reaction with a long latency period
63
what is acute generalised exanthematous pustulosis (AGEP)?
a common cutaneous reaction pattern that is characterized by a sudden eruption that appears on average five days after the medication is started
64
what are the acute phytotoxic drug reactions?
skin toxicity systemic toxicity photodegradation
65
what are the chronic phytotoxic drug reactions?
pigmentation photoageing photocarcinogenesis
66
what are photooptic cutaneous drug reactions?
Non-immunological mediated skin reaction which will arise in any individual providing there is enough photo-reactive drug and the appropriate wavelength of light
67
what is the waveband usually associated with phototoxic cutaneous drug reactions?
UVA/Visible
68
what are the major patterns of cutaneous phototoxicity?
immediate prickling with delayed erythema & pigmentation exaggerated sunburn exponsed telangiectasia delayed 3-5 days erythema & pigmentation increased skin fragility

Dermatology (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions