Chapter 5 Flashcards
Serum lacks which blood components?
Coagulation factors
What does letter ‘c’ & ‘ab’ stand for in Fc & Fab regions of antibody?
Crystallisation
Antibody binding
Name 2 enzymes involved in proteolytic of IgG.
Papain & pepsin
Give 6 entities of Ig superfamily.
IgG TCR Class I MHC CD4 CD28 ICAM-1
Name the regions contributing to hypervariability of antibody.
Name the most variable part of it.
CDR (complement determining regions)
CDR3
Name the structure contributing to flexibility of antibody.
Hinge region
Name 2 classes of light chain of antibody.
Kappa
Lambda
() stabilises multimeric complexes & transport multimers across epithelial cells.
Joining (J) chain
() antibody recognises CDR of another antibody.
Anti-idiotypic
Function of IgA.
Mucosal immunity
Function of IgD.
B cell antigen receptor
Function of IgE.
Defense against helminthic parasites
Immediate hypersensitivity
Function of IgG.
Opsonisation Complement activation ADCC Neonatal immunity Feedback inhibition of B cells
Function of IgM.
Naive B cell antigen receptor (monomeric form)
Complement activation
Name the antibody which has the longest and shortest half-life.
Longest half-life (IgG, 23 days)
Shortest half-life (IgE, 2 days)
Define hybridoma.
Hybrids of normal B cells & myeloma tumour which contain cDNA encoding for monoclonal antibodies.
Synthesis, assembly & expression of Ig molecules are regulated by this group of proteins found in endoplasmic reticulum. What is the collective name for this protein & name its 2 entities.
Chaperones
Calnexin & Binding protein (BiP)
Define class switching.
Expression of Ig heavy chain isotopes other than IgM & IgG.
Define affinity maturation.
Introduction of new amino acid substitution into variable domains of antibody heavy & light chains to create high affinity antibodies.
Why does IgG have the longest half-life?
IgG is able to bind to neonatal Fc receptor (FcRn) which is also involved for IgG transport from maternal circulation across placental barrier.
Which IgG have the longest half-life with most efficient effector functions?
IgG1 & IgG2
Which IgG has the shortest half-life & why?
IgG3 as it binds poorly to FcRn
Define affinity.
Strength of binding between a single combining site of an antibody & epitope.
Define avidity.
Overall strength of attachment
Name 3 zones involved in immune complex formations.
Zone of antigen excess
Zone of equivalence
Zone of antibody excess
Name 3 types of antigenic determinant natures.
Linear epitopes (denaturation) Conformational epitopes (denaturation) Neoantigenic determinant (proteolysis)
