Innate And Adaptive Flashcards by Laura Ang

What are PRRs

Pathogen recognition receptors

How well did you know this?

Not at all

Perfectly

What do PRRs recognise

PAMPs pathogen associated molecular patterns

How well did you know this?

Not at all

Perfectly

What does CXCL8 do?

It is a chemokine that attracts NEUTROPHILS and naive T cells

How well did you know this?

Not at all

Perfectly

What are the non professional immune cells

Fibroblasts and epithelial cells

How well did you know this?

Not at all

Perfectly

What is produced by the oral epithelium that protects the mouth

Antimicrobial peptides like defensins, human neutrophil peptides, cathelicidns, psoriasin)

Lysozymes
Lactoferrin
Secretory IgA
Cystatins
Peroxidase

How well did you know this?

Not at all

Perfectly

What do antimicrobial peptides do (function)

Directly kill microbes (by rupturing membranes or inhibiting intracellar function of bacteria causing lysis)

Modulate host immunity to recruit more immune cells or neutralise bacterial products to suppress inflammation etc

How well did you know this?

Not at all

Perfectly

Secretory IgA function

Adsorb onto the saliva to form protective layer, preventing microbes from adhering to oral mucosa

Bond and Neutralise pathogens

How well did you know this?

Not at all

Perfectly

Lysozyme function

Targets cell walls of bacteria

How well did you know this?

Not at all

Perfectly

Cystatins function

Promote remineralisation
Anti-protease activity

How well did you know this?

Not at all

Perfectly

Function of pathogen recognition receptors

Promote phagocytosis of microbes
Promote activation of immune cells

How well did you know this?

Not at all

Perfectly

Where is TLR2 (TLR6 heterodimer) found on and what does it recognise

It is found on monocytes, dendritic cells, mast cells, eosinophils, basophils

It recognises lipoteichoic acids in gram positive bacteria
Bacteria
Fungi ‘
mycobacterium
Lipoproteins

How well did you know this?

Not at all

Perfectly

What does TLR4 recognise and where is it found on

TLR4 present on macrophages dendritic cells mast cells eosinophils

Recognises LPS (gram negative bacteria)
Recognises lipoteichoic acids (gram positive bacteria )

How well did you know this?

Not at all

Perfectly

What do dectin and glucan receptors recognise

Fungi

How well did you know this?

Not at all

Perfectly

What do NOD-like receptors recognise

Bacterial

How well did you know this?

Not at all

Perfectly

What do protease-activated receptors recognise

Microbial and allergen recognition

How well did you know this?

Not at all

Perfectly

Functions of cytokines

Cytokines are chemical messengers that signal to other immune cells to coordinate an immune response

How well did you know this?

Not at all

Perfectly

What immune cells is most abundant at the oral mucosa

Neutrophils

How well did you know this?

Not at all

Perfectly

What is the function of cell adhesion molecules

They control the interaction between immune cells and epithelial cells, promote cell cell interactions, important for immune tracking

How well did you know this?

Not at all

Perfectly

What are the three main families of cell adhesion molecules

Selectins
Integrins
Immunoglobulin superfamily

How well did you know this?

Not at all

Perfectly

Is M1 or M2 proinflmmtory

M1 is pro
M2 is anti

How well did you know this?

Not at all

Perfectly

Where are cell adhesion molecules found

Cell surface receptors on endothelial cel,s

How well did you know this?

Not at all

Perfectly

What is opsonization

Coating of pathogen with antibodies or complement proteins

How well did you know this?

Not at all

Perfectly

C3 and C5 convertase

Proteins involved in the pathway , destroy the C3 and C5 proteins to obtain fragments which are anaphylatoxins

How well did you know this?

Not at all

Perfectly

Anaphylatoxins function

Lead to smooth muscle contraction and capillary leakage to allow infiltration of immune cells to site of infection

Promote immune cell recruitment

How well did you know this?

Not at all

Perfectly

3 Receptors involved in adaptive immunity

T cell receptors (TCR) B cell receptors (immunoglobulins/i\Ig-) MHC proteins (major histocompatibility complex)

What is the difference between innate receptors and adaptive receptors

Adaptive receptors can specialise and alter genes to develop a repertoire of receptors with wide specificity

What does CD8 corecptor bind to

MHC1

What does CD4 coereceptor bind to

MHC2

What is MHC proteins

MHC molecules are self molecules MHC proteins on self cells tell T cell whether this is our own body cell or a pathogen T cells receptors can only recognise Peptide antigens Peptide antigens are MHC-peptide complexes

What are the components of the T cell receptors

Alpha and beta chains Very small proportion are gamma and delta chains

What are the three gene segments that encode the variable region of TCRs

TCRs have constant and variable region Variable region made up of Variable Diversity Joining

Which gene segment in the variable Region of a TCR has both alpha and beta chains

Variable and joining

Which gene segment that encoded the variable region in a TCR only had beta chain involvement

Diversity section

In relation to TCR, what is the name of the process where genes are rearranged

Somatic recombination

What is the name of the enzyme that drives somatic recombination

RAG enzyme aka recombinase

What is selection in the development of T cells

Non-selection, positive and negative selection It refers to whether the naive T cells pass the checks and are able to recognise self cells before being allowed to differentiate into specific T cells

What is positive selection

If the naive T cell can recognise and bind to the MHC proteins, it can survive Binding is not too strong or weak

What is negative selection

When the naive T cells bind too strongly or weakly to self peptide, apoptosis

Until when are T cells considered mature?

T cells are classed as naive until they recognise and bind to an antigen

What does signal 1 2 3 each mean for T cell differentiation?

Signal 1 determines whether T cells can be activated (ie does TCR recognise and bind to MHC) Signal 2 is the survival and colonial expansion of T cells Signal 3 is the differentiation into subsets of T cells (1) anti- gen recognition, (2) costimulation, and (3) cytokine- mediated differentiation and expansion

What is special about signal 3 for cytotoxic T cells (CD8+ T cells)

Effects are production of perforins and granzymes

Anergy meaning

Signal 1 but no signal 2

What are the two B cell receptors

IgD and IgM

B cells can produce 5 different types of antibodies

IgG E D M A

Most abundant antibody

IgG

Structure of B cell receptors

Light and heavy chain (instead of alpha and beta chains) Variable and constant region

B cells mature in the periphery ie spleen

Does heavy or light chain involve VDJ

Heavy involves V D J Light invokes V J

What is the B cell receptor on immature B cells

IgM

What is the B cell receptors on mature B cells

IgM and IgD

Function of IgG

Class switching from IgM to IgG, most abundant

Function of IgA

Protection at mucosal barrier surfaces

Function of igE

Type 1 Hypersensitivity and allergic reactions, involves basophils and mast cells

Does B cell undergo negative and positive seletkon

No only negative

What is negative B cell selection (central tolerance response)

B cells that bond too strongly to self antigens are eliminated

3 main Functions of antibodies

neutralization activate the complement system to destroy bacterial cells by lysis opsonization

Where are B cells activated

Secondary lymphoid organs like Lymph nodes and spleen

What activates B cells from naive to mature

Thymus dependent antigens and thymus independent antigens

In thymus dependent antigen activation, what T cell and B cell receptor interacts with each other

CD40 on B cell recognises CD40L on T cell The cytokines released from T cells induce proliferation of B cells into memory and plasma cells

In Thymus independent antigen activation, what activates B cells

Certain antigens like LPS (TLR4)

Does thymus independent activation lead to the generation of memory cells?

No memory cells only plasma cells

Why does IgM class switch to IgG

IgM has a weak response IgM has a Low affinity but high avidity IgG has a high affinity (strong binding) but Low avidity (only 2 binding sites)

Why can IgM class switch to IgG?

Because class switching doesn’t affect the antigen binding site, still can recognise the same antigens

Affinity of antibodies

Strength of bonding of single antibody to antigen

Avidity of antibodies

Ability of antibodies to form complexes

Germinal centres

Hubs in lymph nodes where T and B cells cross talk

Central tolerance

Thymus and bone marrow (primary lymphoid organs) Positive and negative selection

Peripheral tolerance if T and B cells manage to bypass central tolerance mechanisms

Need all three signals for T cells T regs also block activity B cells do not differentiate and proliferate because no T cells to release cytokines

3 complement pathways

Classic Alternative Mannose binding lectin MBL

What are IgD and IgM

B cell receptors

What are IgM and IgG

Type 2 hypersensitivity

What activates the classical, alternative and MBL pathway?

Classical - binding of antibody to bacterial surface Alternative- binding of c3b to microbial cell wall MBL- binding of complement protein to carbohydrate

Where do dendritic cells take up and process antigens in the body

Epidermis

Where do mature dendritic cells reside

Lymph nodes , settling in T cells areas

Do NK cells have granules

Yes

Where are ILCs found

Innate lymphoid cells are found mostly at mucosa, barrier surfaces Oral mucosal barrier harbours all ILC subsets

Structure of IgA

Dimeric

Which cells produces CXCL8/IL8

Professional - monocytes and macrophages Non prof - epithelial endothelial fibroblasts

What sort of biological molecule are anaphylatoxins

Glycoproteins

Innate And Adaptive Flashcards

(79 cards)