imunes

Imunes is a term used to describe the immune system and its protective functions in living organisms. Immunity encompasses the complex biological processes that recognize, respond to, and remember foreign substances such as pathogens, toxins, and abnormal cells. The study of imunes is the field of immunology, which covers molecular, cellular, and systemic aspects.

Innate immunity forms the first line of defense and is present from birth. It includes physical barriers such as the skin and mucous membranes, chemical barriers like acidic pH and antimicrobial enzymes, and cellular responses by phagocytes such as neutrophils and macrophages. The innate system also involves the complement cascade and inflammatory signaling that limit spread and recruit more cells.

Adaptive immunity provides targeted, long-lasting protection. It relies on lymphocytes: B cells that produce antibodies (humoral immunity) and T cells that attack infected or malignant cells (cell-mediated immunity). Antigen presentation by dendritic cells and macrophages activates these cells, leading to clonal expansion and immunological memory, so future encounters are fought more efficiently. Major histocompatibility complex molecules present antigens to T cells.

Immunity is not absolute; it can be suppressed (immunodeficiency), exaggerated (allergies), or misdirected (autoimmune diseases). Vaccination, natural infections, and immunotherapies are tools to shape imunes for prevention or treatment. Understanding imunes has led to advances in transplantation, oncology, and infectious disease control.

Note: Imunes is not widely used in English; the standard terms are immunity or immune system.