– Antibodies are special proteins that help your immune system fight off foreign invaders like bacteria, viruses, and toxins. They are produced by a type of white blood cell called a B cell. B cells develop from stem cells in your bone marrow.
– When a B cell encounters an antigen, which is a substance that triggers an immune response, it becomes activated and starts to divide and make copies of itself. These copies are called plasma cells, and they produce millions of antibodies that are specific to the antigen. The antibodies then circulate in your blood and lymphatic system, looking for the antigen and binding to it. This marks the antigen for destruction by other immune cells or makes it unable to infect your cells. Your body can make different types of antibodies, depending on the type of antigen and the type of immune response needed.
– There are five main classes of antibodies: IgA, IgD, IgE, IgG, and IgM. Each class has a different structure and function in your immune system.
– Antibodies are essential for your health and well-being, as they protect you from many diseases and infections. However, sometimes your immune system can make antibodies against your own cells or tissues, causing autoimmune diseases such as rheumatoid arthritis or lupus. Or, your immune system can overreact to harmless substances like pollen or dust, causing allergies or asthma. These conditions can be treated with medications that suppress or modify your immune system.
How do antibodies recognize antigens? How long do antibodies last in the body?
– Antibodies, as earlier defined, are proteins that your immune system produces to fight off foreign substances, such as bacteria, viruses, and toxins. They recognize antigens, which are molecules on the surface of these substances, and bind to them to neutralize them or mark them for destruction by other immune cells.
– The way antibodies recognize antigens is based on their shape and structure. Antibodies have a Y-shaped structure, with two identical arms and a stem. The tips of the arms have regions called antigen-binding sites, which are unique for each antibody and can fit only one type of antigen. The antigen-binding sites are shaped by the variable regions of the antibody, which are segments of the antibody gene that can be rearranged to create different combinations. This allows your immune system to produce a vast diversity of antibodies that can recognize many different antigens.
– The stem of the antibody determines its class and function. There are five main classes of antibodies: IgA, IgD, IgE, IgG, and IgM. Each class has a different structure and role in your immune system. For example, IgA antibodies are found in mucous membranes and body fluids, such as saliva and tears, and protect against ingested and inhaled pathogens. IgE antibodies are involved in allergic reactions and parasitic infections. IgG antibodies are the most abundant and versatile antibodies in your blood and tissues, and can cross the placenta to provide immunity to the fetus.
– The duration of antibodies in your body depends on several factors, such as the type of infection, the type of antibody, and your overall health. Generally, antibodies can last from a few weeks to several months or years after an infection or vaccination. For example, research suggests that COVID-19 antibodies can stay in your body for at least six months after infection.
– However, the level of protection that antibodies provide may vary over time and may not be enough to prevent reinfection by new variants of the virus.
– Therefore, it is important to follow public health guidelines and get vaccinated when possible to boost your immunity against COVID-19.
