Class switching is vital because different immunoglobulin classes (IgM, IgG, IgA, IgE) have distinct roles in immune defense. For example, while IgM is effective in activating the classical complement pathway, IgG is better suited for opsonization and neutralization of pathogens. IgA is crucial for mucosal immunity, and IgE is key in defending against parasitic infections and in allergic responses.
