Question

Which antibody is most abundant in human colostrum?

• A. IgG
• B. IgA
• C. IgM
• D. IgE

Hint:

IgA is the major antibody found in secretions such as saliva, tears, mucus, and colostrum. It plays a crucial role in protecting mucosal surfaces and providing passive immunity to infants.

Answer 1

The Correct Option is B

Concept: Colostrum is the first milk produced by the mother immediately after childbirth. It is rich in proteins, vitamins, minerals, and especially antibodies that provide passive immunity to the newborn. Immunoglobulins (antibodies) are proteins produced by the immune system to fight against pathogens such as bacteria and viruses.

Step 1: Understanding antibodies present in colostrum. Among different types of antibodies (\(IgG\), \(IgA\), \(IgM\), \(IgE\), \(IgD\)), Immunoglobulin A (IgA) is the most abundant in human colostrum.

Step 2: Role of IgA in newborn immunity.
• IgA protects mucosal surfaces such as the gastrointestinal and respiratory tracts.
• It prevents pathogens from attaching to the mucous membranes.
• It provides passive immunity to the newborn during the early stages of life.

Step 3: Conclusion. Therefore, the antibody most abundant in human colostrum is IgA.