immuniteter

Immuniteter is a term used to describe the immune system and its capacity to defend the body against pathogens and abnormal cells. It includes the collective components, processes, and regulation that detect, respond to, and remember foreign invaders, while maintaining tolerance to the body's own tissues.

The immune system is divided into innate and adaptive branches. Innate immunity provides immediate, broad protection through physical barriers such as the skin and mucous membranes, chemical defenses, and immune cells like macrophages, neutrophils, eosinophils, and natural killer cells. It uses pattern recognition receptors to detect common features of microbes.

Adaptive immunity offers targeted, specific responses and immunological memory. It relies on antigen-presenting cells to activate T and B lymphocytes. B cells produce antibodies that neutralize pathogens and mark them for clearance, while T cells coordinate responses, kill infected cells, and help B cells. Memory cells ensure faster responses upon re-exposure.

Regulation and development: immune competence depends on genetics, development of primary lymphoid organs (bone marrow, thymus), and cues from the environment. Imbalance can lead to immunodeficiency, autoimmunity, allergies, or inflammatory diseases. Vaccination is a key tool for shaping immuniteter by training adaptive immunity.

In medicine and research, immuniteter is central to immunotherapies, diagnostics, and epidemiology. Understanding its components helps in treating infections, cancer, and immune-mediated diseases, as well as in designing public health strategies.