ACAAI Review for the Allergy & Immunology Boards Flash Cards CHAPTER 1

Small-molecule antigen requires covalent linkage to a larger carrier to stimulate adaptive immune response. The process is achieved in collaboration between hapten-specific B cells and carrier-specific T cells. This is the basis of developing conjugated v

What is the hapten-carrier effect?

SEB and SEC from Staphylococcus aureus cause food poisoning. TSST from Staphylococcus aureus and SPE-C from Streptococus pyogenes cause toxic shock syndrome.

What are the common superantigens and related diseases?

Natural killer T (NKT) cells recognize lipid antigens, and the CD1 molecule is involved.

Which type of T cell recognizes lipid antigens and what molecule is involved?

Protein antigens are T-cell dependent. Polysaccharide, nucleic acid, and lipids are T-cell independent.

Which antigens are T-cell dependent and which are T-cell independent?

On the MHC class I molecule, ?3 is the binding site for CD8. On the MHC class II molecule, ?2 is the binding site for CD4.

What is the binding site for CD4 on the MHC class I molecule? What is the binding site for CD8 on the MHC class II molecule?

On the MHC Class I molecule, ?1 and ?2 make up the peptide binding cleft. On the MHC class II molecule, ?1 and ?1 make up the peptide binding cleft.

Which chain makes up the peptide binding cleft in MHC class I molecules? Which chain makes up the peptide binding cleft in MHC class II molecules?

An MHC class I molecule presents both intracellular antigens (e.g., viral antigen in cytoplasm) and extracellular antigens (via cross-presentation). The loading site is endoplasmic reticulum (ER).

MHC class I molecule presents which type of antigens and where does the antigen-MHC class I loading happen?

The MHC class II locus. They are involved in peptide processing for MHC class I however.

In which chromosomal region are the TAP proteins located?

The MHC class II molecule presents extracellular antigens (e.g., antigens from phagocytosed bacteria). The loading site is phagolysosome.

MHC class II molecule presents which type of antigen? Where does the antigen-MHC class II loading happen?

IL-10 and TGF?

Which cytokines are important for Tregs?

TCR, MHC molecules, CD4, CD8, CD19, B7-1, B7-2, Fc receptors, KIR, and VCAM-1

What molecules belong to the Ig superfamily?

Junctional diversity; TdT enzyme is important in this process.

Which somatic recombination process introduces the greatest diversity in immune receptors and which enzyme is important in this process?

The FcRn receptor binds to IgG and allows it to be endocytosed. It protects it from the lysosome and instead recycles it to the cell surface. This accounts for the long half-life of IgG in humans. This is also the mechanism by which IgG is transported acr

What is the role of the FcRn receptor?

X-linked lymphoproliferative syndrome (XLP)

Mutation in SAP causes which disease?

Cyclosporine binds to cyclophilin, which are proteins also called immunophilins. The drug-protein complex inhibits calcineurin and therefore NFAT translocation to the nucleus.

Immunosuppressant cyclosporine binds to which molecule in T-cell signaling pathway?

CD21, CD19, and CD81

What CD molecules are in the BCR coreceptor?

CXCR4

Which chemokine receptor is associated with WHIM (warts, hypogammaglobulinemia, infections, and myelokathexis) syndrome?

?4?7

Which integrin molecule is important for gut homing by binding to MAdCAM?

4-10 days

Upon first exposure to a medication, when might a patient develop symptoms of serum sickness?

IL-4 R?, which is targeted by dupilumab

Which component is shared by IL-4 and IL-13 receptors?

IFN? receptor deficiency results in susceptibility to Mycobacterium tuberculosis and other intracellular bacteria.

What is the result of IFN? receptor deficiency?

IL-1?

What interleukin is excessively produced in cryopyrinopathies?

Lipopolysaccharide responsive beige-like anchor protein (LRBA) deficiency

What disease presents with early onset hypogammaglobulinemia with autoimmunity and immune dysregulation?

It maintains intracellular stores of CTLA4, which can stop T-cell activation.

What is the function of LRBA?

Properidin

Which complement deficiency is inherited as X-linked?

CD 59 and S protein

What two molecules inhibit MAC formation?

CD 55 and CD 59

Which complement receptor is implicated in PNH (paroxysmal nocturnal hemoglobinuria)?

Adipose tissue

What is the main source of Factor D?

HUVS (hypocomplementemic urticarial vasculitis)

Anti-C1q antibody is found in which disease process?

Factor XII

Contact activation pathway is initiated by which factor?

B-2 receptor

Bradykinin acts on what receptor on endothelial cells?

IgG and IgM

What are the primary immunoglobulins involved with type II hypersensitivity?

Classical pathway

IgG and IgM activate which complement pathway?

Both are type III hypersensitivity reactions; however, serum sickness is systemic and arthus reaction is local

How are serum sickness and arthus reaction similar and different?

Innate immunity and adaptive immunity

Complement activation is involved with what types of immunity?

PAMPS

How do receptors of the innate immune system recognize microorganisms?

NODs

What receptor is involved with the inflammasome?

TLR 3

Which TLR does not signal through MyD88?

TLR 4

Which TLR can signal through both MyD88 dependent and independent pathways?

TLR 3, 7, 8, and 9

Which TLRs are present in the intracellular compartment and implicated in HSV1 encephalitis?

PAMPs are conserved microbial sequences from microorganisms whereas DAMPs are endogenous molecules derived from damaged or dying cells.

How do PAMPS differ from DAMPs?

TLR 4

Which TLR binds lipopolysaccharide (LPS) on gram-negative bacteria?