Question

1. True/False:
Like innate sensors of infections(TLRs, NLRs, RL Rs), antibodies frequentlyrecognize nucleic acids of pathogenic organisms.

2. Antibodies that bind with high affinity to some viral surface proteins require heavy chain CDR3 loops of unusual length. Whereas the average human heavy chain CDR3 length is ~15 amino acids, antibodies with VH CDR3 loops of >30 amino acids are readily detected in the repertoire. These antibody heavy chains with CDR3 lengths of >30 amino acids would likely be missing in individuals lacking:
A. RAG-1 and RAG-2
B. DNA-dependent protein kinase (DNA-PK)
C. The nuclease, Artemis
D. The Ku70:Ku80 complex
E. Terminal deoxy nucleotidyl transferase (TdT)

3. True/False:
The different classes of
immunoglobulins differ in the sequences of their
heavy chain constant regions. As a result, each
class of antibody has distinct effector functions.
Nonetheless, they are all found at about equal
concentrations in the serum of healthy
individuals.

Answer 1

1. Answer: False.

Antibodies usually recognize the surface structure of pathogen of folded antigen or toxin. For exapmple, viral coat protein of carbohydrate receptors of bacterial polysaccharides.

2. E. Terminal deoxy nucleotidyl transferase (TdT)

3. False

It is true that The different classes of immunoglobulins differ in the sequences of their heavy chain constant regions. As a result, each class of antibody has distinct effector functions. But the serum concentration of different classes of antibodies differ in our body. IgG is the most abundant and IgD is the least abundant antibody in our body in normal conditions.