Which statement about anti-Jk^a is true?

Which statement about anti-Jk^a is true?

• A. It is usually IgG and AHG reactive.
• B. It is IgM
• C. It is IgA
• D. It is IgE

Answer: (A)

Anti-Jk^a antibodies are typically IgG, and they react during the antiglobulin (AHG) phase. This combination makes them clinically significant because IgG antibodies can bind red cells in vivo and at body temperature, leading to hemolytic transfusion reactions or delayed hemolysis if antigen-positive blood is given. They can also cross the placenta. In contrast, IgM antibodies usually react at immediate spin (room temperature) and are less likely to cause transfusion problems, while IgA or IgE are not the usual isotypes involved with anti-Jk^a.

Anti-Jk^a antibodies are typically IgG, and they react during the antiglobulin (AHG) phase. This combination makes them clinically significant because IgG antibodies can bind red cells in vivo and at body temperature, leading to hemolytic transfusion reactions or delayed hemolysis if antigen-positive blood is given. They can also cross the placenta. In contrast, IgM antibodies usually react at immediate spin (room temperature) and are less likely to cause transfusion problems, while IgA or IgE are not the usual isotypes involved with anti-Jk^a.