Answer: IL-4 is involved in the differentiation of native T cells to the Th2 cells (Option B).
Step-by-step explanation:
a) B cell suppression: B cell suppression is not a primary function of IL-4. IL-4 actually plays a role in stimulating B cells to differentiate into antibody-producing plasma cells.
b) Differentiation of native T cells to the Th2 cells: IL-4 is a cytokine that is crucial for the differentiation of naive T cells into a specific subset known as Th2 cells. Th2 cells are involved in immune responses against parasitic infections and allergic responses.
c) MHC class switching: MHC class switching refers to the process by which B cells change the type of antibody they produce. While IL-4 does play a role in stimulating this process, it is not its primary function.
d) Systemic inflammation: Systemic inflammation is typically associated with the production of pro-inflammatory cytokines such as IL-1 and TNF-α. IL-4, on the other hand, is an anti-inflammatory cytokine and is not directly involved in systemic inflammation.
In summary, among the given options, IL-4 is primarily involved in the differentiation of native T cells into Th2 cells. Th2 cells are important for immune responses against parasites and allergies.