Description: Antibodies are specialized proteins produced by the immune system in response to the presence of pathogens, such as viruses and bacteria. These molecules are fundamental for the body’s defense, as they bind to antigens, which are foreign substances that trigger an immune response. Antibodies are highly specific, meaning that each type of antibody targets a particular antigen. They are produced in B lymphocytes, a type of immune cell, and their structure consists of two heavy chains and two light chains, forming a ‘Y’ shape that allows them to effectively bind to antigens. In addition to their role in neutralizing pathogens, antibodies can also activate other parts of the immune system, such as the complement system, to eliminate threats. Their relevance extends beyond biology, as they are key tools in biomedical research and the development of therapies and diagnostics, including serological tests and treatments for autoimmune diseases and cancer.
History: The discovery of antibodies dates back to the late 19th century when Emil von Behring and Kitasato Shibasaburo demonstrated that serum from immunized animals could protect other animals from infectious diseases. This finding led to the development of serum therapy and laid the groundwork for modern immunology. In 1900, Paul Ehrlich introduced the concept of ‘antibody’ and proposed that these proteins were responsible for immunity. Throughout the 20th century, significant advances were made in understanding the structure and function of antibodies, including the identification of different classes of antibodies, such as IgG, IgM, IgA, IgE, and IgD.
Uses: Antibodies have multiple applications in medicine and research. They are used in clinical diagnostics, such as tests for infectious diseases (e.g., HIV, hepatitis) and in the identification of biomarkers for various conditions. In therapies, monoclonal antibodies are employed to treat diseases such as cancer, autoimmune diseases, and inflammatory disorders. Additionally, antibodies are essential tools in biomedical research, allowing for the visualization and purification of proteins, as well as the study of molecular interactions.
Examples: A notable example of antibody use is trastuzumab, a monoclonal antibody used in the treatment of HER2-positive breast cancer. Another example is the ELISA (Enzyme-Linked Immunosorbent Assay) test, which uses antibodies to detect the presence of antigens in biological samples, such as blood or serum. Additionally, antibodies are used in research to label specific cells in cell biology studies.
