The immediate spin phase is used to detect antibodies of which immunoglobulin class?

The immediate spin phase is used to detect antibodies of which immunoglobulin class?

• A. IgA
• B. IgG
• C. IgE
• D. IgM

Answer: (D)

The immediate spin phase detects antibodies that can cause red cell agglutination at room temperature without incubation, which are typically IgM antibodies. IgM is a large pentamer that readily cross-links antigens on neighboring red cells and produces visible agglutination in this quick mix. In contrast, IgG antibodies are smaller and usually require incubation and the antiglobulin (AHG) phase to be detected, while IgA and IgE are not typically involved in standard immediate spin testing.

The immediate spin phase detects antibodies that can cause red cell agglutination at room temperature without incubation, which are typically IgM antibodies. IgM is a large pentamer that readily cross-links antigens on neighboring red cells and produces visible agglutination in this quick mix. In contrast, IgG antibodies are smaller and usually require incubation and the antiglobulin (AHG) phase to be detected, while IgA and IgE are not typically involved in standard immediate spin testing.