ABSTRACT:

Interleukin-4 (IL-4) is one of the most important immunomodulatory cytokines. Although it is thought of purely as acting on the differentiation of T helper cells, IL-4 can polarize macrophages. That is why knowledge of the biochemical pathways and molecular mechanisms of IL-4 action is needed. Various biological activities have been ascribed to IL-4, including immune responses, inflammation, and tissue homeostasis. This wide range of activities is likely to be based on defined pathophysiological features in diseases within the nervous system and allergic disorders. Hence, this review attempts to compile the most recent findings regarding the pathophysiological functions of IL-4, focusing primarily on its contribution to neuroinflammation, macrophage polarization, and allergic responses. In conclusion, IL-4 is a multifaceted cytokine that plays crucial roles in immune responses, influencing macrophage polarization, tissue repair, and inflammation across various biological systems. Continued research into its biochemical pathways and interactions with other cytokines will be essential for harnessing its therapeutic potential in treating inflammatory and autoimmune diseases. The pathophysiology of IL-4 is multifaceted, influencing both immune responses and neural health. Its roles in microglial polarization, neuroinflammation, and allergic diseases highlight its significance as a therapeutic target. Despite the progress made in understanding IL-4’s functions, further research is necessary to unravel its complex signaling mechanisms and to explore its potential in clinical applications across various pathological conditions.

KEYWORDS :

Biochemistry, Pathophysiology, Clinical Importance, IL-4.
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