Which is an example of artificial passive immunity?

• A. Administration of monoclonal antibodies or immune globulin
• B. Vaccination
• C. IgG transferred from mother to fetus across the placenta; IgA in breast milk
• D. IgA in breast milk

Answer: (A)

Artificial passive immunity involves giving someone preformed antibodies from an outside source to provide immediate protection, without their immune system having to make the antibodies itself. Administering monoclonal antibodies or immune globulin is the classic example: antibodies are produced in the lab and then given directly to the patient, offering quick, short-term protection or treatment. This contrasts with vaccination, which stimulates the person’s own immune system to produce antibodies—an active immunity process that takes time to develop. Maternal transfer of IgG across the placenta or IgA in breast milk is natural passive immunity, since the antibodies come from the mother rather than from a drug.