Interleukin-4 (IL-4) is a cytokine that is primarily produced by activated T cells, mast cells, and basophils.
It plays a critical role in regulating the immune response, specifically in promoting an immune response known as the Th2 response.
Interleukin 4 (IL4) is produced by CD4+ T cells specialized in providing help to B cells to proliferate and to undergo class switch recombination and somatic hypermutation to the IgG1 and IgE isotypes.
IL-4 stimulates the differentiation of naive T cells into Th2 cells, which are a subset of T helper cells that are involved in antibody production and immune responses against parasites and allergens.
IL-4 also promotes the growth and activation of B cells, leading to the production of immunoglobulin E (IgE), which is important in allergic responses.
Furthermore, IL-4 is known to inhibit the production of certain cytokines involved in the Th1 response, which is associated with cellular immunity and defense against intracellular pathogens.
This suppression of Th1 cytokines helps to maintain the balance between Th1 and Th2 responses in the immune system.
IL-4 is implicated in promoting tissue repair processes, such as wound healing and tissue remodeling, and can contribute to the development of certain diseases, such as asthma and allergic reactions.
Overall, interleukin-4 plays a crucial role in modulating the immune response, promoting allergic reactions, stimulating the production of antibodies, and influencing tissue repair processes. Its functions are carefully regulated and its dysregulation can contribute to immune disorders and allergic diseases.