Ónæmisviðbragð

Ónæmisviðbragð is the Icelandic term for immune response. It refers to the complex series of reactions that occur within the body when it encounters foreign substances, known as antigens. These antigens can include pathogens like bacteria, viruses, fungi, and parasites, as well as non-infectious substances such as pollen or toxins. The primary goal of an immune response is to detect, neutralize, and eliminate these harmful agents, thereby protecting the body from disease and maintaining health.

There are two main types of immune responses: innate immunity and adaptive immunity. The innate immune system provides a rapid, non-specific defense that is present from birth. It includes physical barriers like skin and mucous membranes, as well as cellular components such as phagocytes (cells that engulf and destroy foreign particles) and natural killer cells. This system acts as the first line of defense and can quickly control infections.

Adaptive immunity, on the other hand, is a more specialized and slower-developing response. It is characterized by its specificity, meaning it targets particular antigens, and its memory, meaning it remembers previous encounters with pathogens. This allows for a faster and stronger response upon re-exposure. Key players in adaptive immunity are lymphocytes, specifically B cells which produce antibodies, and T cells which can directly kill infected cells or help regulate the immune response. The coordinated action of these two systems ensures effective protection against a vast array of threats.