Hypersensitivity

Flashcards about hypersensitivity lecture

What are the three components that Thomas Lewis characterized inflammation as?

Redness, flare, and swelling

What does 'dermo' mean in the condition known as Dermatography?

Skin

What is the fluid-filled part of inflamed tissue called?

The Wheal

What is the redness that comes alongside inflammation called?

The Flare

What is histamine's role in acute inflammation?

It is potent and pro-inflammatory.

What does Histamine do to the cells?

Histamine weakens the cells.

What is the effect of histamine on the junctions between the vascular endothelium?

It weakens them.

What effect does the weakened endothelial cells have on the tissue?

It allows the tissue to become a lot more permeable to things, largely cells.

What is the first iteration of adhesion molecules that anchor neutrophils?

Selectins

What are the stronger adhesion molecules that neutrophils use to migrate slowly along the blood vessel?

Integrins

What is the function of T regulatory cells?

They seek to do the opposite of the effector cells.

What is one function of the T regulatory cells?

Suppressing dendritic cell activity

How do T regulatory cells antagonize a nave T cell activation?

Via MHC II through the like three receptor or antagonizing CD28 through CTLA-4.

What can targeting CTLA-4 with certain cancer therapeutics help facilitate?

Clearance of that cancer cell

What is adenosine's function?

Inhibitory cytokine used to limit T effector cell responses

What do T regulatory cells gobble compared to standard CD4 positive cells?

IL-2

What is the effect of Tregs binding to the adenosine receptor?

Causes cyclic AMP reduction that will cause a downregulation in um T effector cell metabolic profile.

What role do Tregs play in hypersensitivity?

A critical one in prevention.

What is skewed to a T regulatory cell phenotype?

A subset of CD4 cells recognizing self-antigen because it's in sites they won't encounter.

What happens when an antigen presenting cell interacts with a the CD4 cell with a high amount of anti-inflammatory cytokines?

The TGF-beta also will cause it to become an induced T regulatory cell.

What are the four different classes of Hypersensitivity?

Type 1, 2, 3, and 4.

Which hypersensitivity types are mediated by immunoglobulins?

Types 1, 2, and 3.

What immunoglobulin drives type one hypersensitivity?

IgE.

What is the most concerning aspect of a type 1 hypersensitivity reaction?

Anaphylaxis.

What is Anaphylaxis?

Where you need to give someone an EpiPen to counteract the activity of the histamine

Besides histamines, what accounts of certain results of hypersensitivity?

Eosinophilia/Eosinophils

In individuals with allergies, what have they failed to do?

T regulatory cell training

A pathogenic peptide that looks eerily similar to a host peptide is known as what?

Molecular Mimicry

What is the main component that causes type one hypersensitivity reactions?

A Mast Cell

What does non-immunologic activation of mast cells refer to?

Different aspects that are not pathogenic in nature.

What does immunologic activation of mast cells refer to?

Primarily to immunoglobulins.

A well known antibiotic is known to effect mast cells, what is it?

Vancomycin

Histamine binds to what receptors on smooth muscle to promote vasodilation?

H1 receptors

In the lungs, what affect does the act of Histamine have?

Histamines constrict the bronchioles of the lungs.

What is known as the sensitization step?

The idea that you've encountered this allergen

What is asthma driven by?

Largely it's going to be kind of microparticles like dust.

Non-immune food-mediated reasons is a result of what?

You might have genetic absence of something.

What is usually done to treat allergies?

Can use an anti-IgE

When does rhesus antigen become a problem?

During the delivery of of a neonate for the first time to a rhesus negative other.

What is given at a neonatal appointment in a pregnant person that's rhesus negative?

You would then just supplement them with an anti-rhesus antibody.

What is given if you don't know a blood type in need of a blood transfusion?

O-negative blood

Define Goodpasture Syndrome.

Antibodies to a type of collagen that exists on the basement membrane of cells.

What are type three hypersensitivity reactions down to?

Immune complexes

What kind of antibodies can be found with someone diagnosed with Systemic Lupus Erythematosus?

Anti-DNA antibodies

When we are trying to see if we need vaccination against tuberculosis we use what reaction?

Arthus reaction

Type Four Hypersensitivity is largely driven by what response?

Cell-mediated immunity

What is the delayed reaction a result of?

The T1 cells are then releasing cytokines

After tuberculin is put into action, it's recommended to give 48 to 72 hours. What happens if it looks bad?

It then means that the T cells that are already sensitized in the tissue have been through this immune response before

What is contact dermatitis?

This is just where you encounter something on your skin, and it makes your immune cells quite unhappy.

High levels of what mutation can be tied to coeliac disease.

DQ region.