Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

immunlogy > Immunologic and inflammatory disorders/ T cell development > Flashcards

Immunologic and inflammatory disorders/ T cell development Flashcards

1
Q

——————- :a variety of proliferative disorders ‘macrophages’ (= over-production of white blood cells = histiocytes)

A

Histocytosis

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

Histiocytes can lead to ———- and ———–formation

A

Histiocytes can lead to organ damage and tumour formation

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

Is Langerhans cell histocytosis a sytemic disease?

A

Yes

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

What are langerhans cells?

A

type of WBCs that help the body fight infections (provide immunity)

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

bulidup of langerhans cells in certain body parts will lead to?

A

tumours or organ damage

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

LCH in children vs Adults

A

children –> acute disseminated multisytem disease
Adults –> Indolent Single organ disease

* indolnet –> slowly growing

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

Piutuitary invlovlement in LCH in adults is assocaited w?

A

Diabetes Insipidus

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

Calssification of langerhans cell Histocytosis

A

1) Acute disseminated LCH (Letterer - Siwe ds)
2) Multifocal LCH- multifocal eosinophillic granuloma ( Hand-Schuller-Christian disease)
3) Unifocal LCH - Unifocal Eosinophilic granuloma

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

CF of Acute disseminated LCH (Lettere- Siwe disease)

A
  • mainly occur before the age of 2
    1) Cutaneous abnormalities are present in almost 80% of patients (trunk and scalp)
    2) hepatosplenomegaly
    3) lyphadenopathy
    4) lung involvement
    5) destructive osteolytic bone lesions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

In Acute disseminated LCH (Letterer - Siwe disease), when extensive BM involvement occurs pateints present w?

A

1) anemia, thrombocytopenia
2) recurrent infection (otitis media, mastoiditis)
3) if untreated can rapidly be fatal
(with intensive chemotherapy 50%, 5 year survival)

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

where are Langerhan cells found

A

Skin, spleen, lungs, bone marrow, liver, lymph nodes, skull

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

in Chronic Unifocal LCH bony lesions may cause ———?

A

Otitis media

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

CF/Epi of Multifocal LCH (Multiple Eosinophilic granuloma)

A

Classic HSC triad : Calvarian bone defects , exophthalmus , DI

  • Epi : 2-4 yrs

* Calvarian bone : skull

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

CF/Epi of Unifocal LCH - unifocal eosinophilic granuloma

A
  • Epi: age 5-15 years

1) Solitary clavarial lesions - solitary lesion of skull / vertebra /rib / mandible/ femur / ilium / scapula
2) Asymptomatic/ tenderness
3) an indolent disease (relatively benign)

* if clavarial lesion extend to the nervous system theyll cause neuro sx

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

which type of Histocytosis is associated w/ Tobacco smoking

A

Pulmonary LCH X
(Uncommon intersitital lung disease)

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

Epi of Pulmonary LCH X

A
  • intersitial lung disease ass. w/ Smoking (tobacco)
  • Affects young adults
  • benign, RARE
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

CF of Pulmonary LCH X

A

1) Nonproductive cough (56-70%)
2) Dyspnea (40%)
3) Fatigue (30%)
4) Weight loss (20-30%)
5) Chest pain (21%)
6) Spontaneous pneumothorax, which may be recurrent, is a classic presentation found in 10-20% of patients
7) Fever (15%)
8) Cystic bone lesions (4-20%): These may be painful and may predispose the patient to pathologic fracture

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

what makes up a granuloma?

A

collection of Organized macrophages (ask Histocytes)

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

most common cause of lung granulomas?

A

fungal infections that primarily affect the lungs

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

Granulomas are most often the result of an ——— and most frequently occur in the ————, but can occur in other parts of the body as well

A

Granulomas are most often the result of an infection and most frequently occur in the
lungs, but can occur in other parts of the body as well

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

Apart from infections, ——- conditions can also cause granulomas

A

Autoimmune systemic conditions

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

Examples of Autoimmune systemic conditions

A

SLE, rheumatid arthritis, scelroderma

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

chracteristics of a granuloma

A

1) inflammation
2) fungal infections in the lungs
3) Autoimmune systemic conditions

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

macrophages in granulomas are often referred to as ”————-“

A

macrophages in granulomas are often referred to as “epithelioid”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

TURE/FALSE
Loosely dispersed macrophages are not considered to be granulomas

A

True
they must be organized

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

infections that are characterised by granulomas

A

1) TB
2) leprosy,
3) histoplasmosis, cryptococcosis, coccidioidomycosis,
blastomycosis and cat scratch disease

27
Q

Non-infectious Granulomatous diseases

A

1) sarcoidosis,
2) Chron’s disease,
3) berylliosis,
4) granulomatosis with polyangiitis,
5) eosinophilic granulomatosis with polyangiitis,
6) pulmonary rheumatoid nodules
7) Wegener granulomatosis

28
Q

———–: multisystem inflammatory disease, that manifests as non-caseating granulomas,
predominantly in the lungs and intra-thoracic lymph nodes

A

Sarcoidosis

29
Q

CF of Sarcoidosis

A

1) Lupus pernio (painful skin sores on face)
2) Lesion on back, arms, neck, face and scalp
3) Enlarges lymph nodes (in chest near wind pipe adn lungs)
4) Scarring and granulomas in lung
5) Spleen enlargment
6) Heart complications (rare)
7) Conjuctival lesions and scleral plaques
8) Anterior/ posterior granulomatous uveitis (most frequent)
9) crackel sounds in the lungs
10) Erythema nodosum
11) Violaceous rash on the cheeks or nose (common)

30
Q

One of the main featurs of Wegner’s granulomatosis (GPA)

* GPA - granulomatosis w/ polyngiitis

A

Vasculitis

31
Q

CF of Granulomatosis w/ polyngiitis (Wegner’s ganulomatosis)

A

1) recurrent respiratory infection in Adults
2) upper and lower respiratory tract problems in children
3) Fevers, night sweats
4) Fatigue, lethargy
5) Loss of appetite
6) Weight loss

32
Q

CF:
* Typical Saddle nose damage
* Sclerokeratitis
* Vasculitis

are features of?

A

Wegener’s Granulomatosis
= GPA granulomatosis w/ polyangiitis

33
Q

cell mediated vs Humoral immune respose

A
  • Cell mediated immunity (T cells)–> does not produce Ag specific Abs
  • Humoral response (B cells) –> produces Ag-specific Abs
34
Q

where does the development of T cells take palce

A
  • produced in the Bone marrow
  • mature in the thymus
35
Q

Mature T cells leaving the thymus, are diverse in their specificities and are both —————-and restricted to ————-

A

Mature T cells leaving the thymus, are diverse in their specificities and are both tolerant to self and restricted to self-MHC

36
Q

T cells undergo development in the ——— and migrate to the —————, where they are activated by foreign antigens

A

T cells undergo development in the thymus and migrate to the peripheral lymphoid organs, where they are activated by foreign antigens

37
Q

developing T cells are called ———-

A

Thymocytes

38
Q

the 2 events of T-cell development

A

1) Early thymocyte development –> T-cell receptor independent
2) Selection events –> T-cell receptor dependent

39
Q

VERY early thymocyte development occurs in the ———–

A

Bone marrow

40
Q

The 3 stages pf Thymocyte Development

A

1) Early thymocyte development
2) Positive and negative selection
3) Lineage commitment

41
Q

Immature T-cells (progenitor cells) migrating from the BM to the Thymus [Express/ do not Express] Ag receptors/ CD4 or CD8 or CD3

A

Do not Express

42
Q

In Early thymocyte development Cells go through a series of different stages, what are they?

A

1) Double negative (DN) no CD4 or CD8 expression CD4-CD8
2) Double positive (DP)—both CD4 and CD8 (TCR expressing
3) Recombination of TCR gene segments occurs in the DN stages

43
Q

What is lineage commitment?

A

Its when selceted thymocytes mature to become SP (single positive) , Where thye either become CD4+ or CD8+ T cells

  • Note:
    this happens after positive and negative selection (so Thymocytes that have passed the +ve selection will undergo Lineage commitment)

* First DN –> DP –> SP

44
Q

Selected thymocytes mature to become single positive (SP), where only CD4 or CD8 are expressed, this is known as?

A

Lineage Commitment

45
Q

Exaplin what happnes during the selection events of Thymocyte development

A

Positive/ Negative selection satges :

1) Postive selection –> selection for those cells whose TCR respond to self-MHC
2) Negative selection –> selection against those cells whose TCR reacts strongly to self-peptide/MHC combinations
3) selected thymocytes (the ones passing positive selection) –> are realeased into the peripheral bloodstream

46
Q

T-cell development in the cortex

1) DN: once they encounter the thymic environment they ———–
2) DN: ————- begins to rearrange
3) DN: those that have successfully rearranged β-chain form ———— , they proliferate and mature to ———
4) DP: initiation of ———– chain, if successful then ——— is expressed and cells are ready for the second stage of T cell development (———-)

A

1) DN: once they encounter the thymic environment they proliferate
2) DN: β-chain begins to rearrange
3) DN: those that have successfully rearranged β-chain form pre-TCR , they proliferate and mature to DP
4) DP: initiation of TCRα chain, if successful then TCR is expressed and cells are ready for the second stage of T cell development (selection)

47
Q

————– ensures only one β-and α-chain are expressed per cell during the early thymocyte development

A

Allelic exclusion

48
Q

Surface molecules expressed during development of T-cells (during the DN and DP stage)

A

RAG1/RAG2 and TdT

49
Q

why is thymic selection necessary?

A

Randomly generated TCRs can recognize all possible MHC/peptide combinations–> dangerous (they will attack “self”)

  • note:
    i.e. recognize foreign MHC/peptides – not useful
    i.e. recognize self MHC/self peptides – dangerous!!!!
    i.e. recognize self-MHC forgein-peptide- useful
50
Q

Positive selection ensures ————-

A

MHC restriction

51
Q

how does positive selection ensure MHC restriction?

A

Selects thymocytes bearing T cell receptors (TCR) capable of binding self-MHC molecules, allowing the creation of a self-MHC restricted T cell repertoire

* repertoire : store/ collection

52
Q

Negative selection ensures ————

A

Self-tolerance (Central tolerance)

53
Q

Negative selection happens in the ———— and the ——– of the thymus and eliminates T cells that bind too strongly to self-MHC+ self peptide
(———————)

A

Negative selection happens in the cortex and the medula of the thymus and eliminates T cells that bind too strongly to self-MHC+ self peptide
(central tolerance)

54
Q

cells involved in the +ve/-ve selection of thymocyte development

A

Cortical and medullary thymic epi cells, macrophages and DCs

55
Q

Funtion of cortical and medullary thymic epi cells, macrophages and DCs?

A

1) Express MHC I and II
2) developing T cells interact w/ these cells through TCR-CD3

56
Q

Cortical and medullary thymic epi cells, macrophages and DCs play important roles in the selection
* These cells express MHC I and II and developing T cells interact with them through their ————-

A

TCR-CD3

57
Q

Developing T cells that can bind MHCs shift from —— to ——-

A

DP –> SP
* If the TCR can bind to an MHC class II molecule, it becomes a CD4+ cells
* The opposite happens if the TCR binds to an MHC class I molecule, it becomes a CD8+ cell

58
Q

How are developing T cells checked against self- antigens that are not expressed in the thymus?

A

The thymus expresses and presents proteins from all the body, those are presented to —> AIRE, expressed by medullary thymic epithelial cells (mTECs), which eliminate autoreactive T cells –> preventing them from being released into the peripheral bloodstream

59
Q

Maturation of T cells happens in the Thymus, in which part does final maturation occur
1) Thymic medulla or
2) Thymic cortex ?

A

Medulla

60
Q

While most self-reactive T cells will be deleted in the thymus, a small population of these T cells will instead differentiate into ————

A

TREG cells

61
Q

T regulatory cells (Tregs) belong to a subset of CD4+ T cells charcaterized by constitutive expression of ——–, —— and ——— transcription factor

A

They belong to a subset of CD4+ T cells characterized by constitutive expression of CD4, CD25 and FoxP3 transcription factor

62
Q

What cytokines are secreted by Tregs?

A

IL-10 and TGF-β

63
Q

fx of IL-10 and TGF-β

A

anti-inflammatory Cytokines released by Tregs (inhibit inflammation)

64
Q

How do Tregs serve in peripheral tolerance?

A

when they leave the thymus they inhibit the fxn of escaping autoreactive T cells

immunlogy (18 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions