PATHOLOGY

PATHOLOGY MCQ

IMMUNE RESPONSE

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
How long does Immunoglobulin G circulate in serum providing protection?
A
Months to Years
B
Weeks to Months
C
Less than 72 hours
D
5-10 Days
Explanation: 

Detailed explanation-1: -Different antibody isotopes are present in human sera (IgM, IgA and IgG). They each have relatively limited half-lives, with a maximum of 17.5–26.0 days for Immunoglobulin G (IgG), which represent about 75% of the antibody isotopes in humans [2], [3], [4].

Detailed explanation-2: -IG is available either as 5% (50 mg/dL) or 10% (100 mg/dL) liquid or as lyophilized preparations. As the name suggests, IVIG is administered intravenously, and the half-life of a typical intravenous immunoglobulin infusion is about 3 to 4 weeks.

Detailed explanation-3: -In humans, the average half-life of IgG in circulation is approximately 3 weeks2 and in mice it is 6–8 days3. However, in FcRn−/−mice the half-life of IgG in circulation is reduced to 1 day4 and the mice cannot maintain IgG homeostasis, resulting in a 70–80% reduction of the total level of IgG.

Detailed explanation-4: -IgG could be detected as early as 4 days after the onset of illness.

There is 1 question to complete.