Immunochemistry & Immunopathology

Immunology is the study of the immune system and its response to various pathogens, including infectious diseases. The immune system is a complex network of cells, tissues and organs that work together to protect the body from harmful microorganisms such as bacteria, viruses, fungi and parasites. When a pathogen enters the body, the immune system recognizes it as foreign and mounts a response to eliminate it. This response involves several key components. The innate immune system provides the first line of defence against pathogens. It includes physical barriers like the skin and mucous membranes, as well as immune cells such as neutrophils, macrophages and natural killer cells. These cells can recognize common features of pathogens, called Pathogen-Associated Molecular Patterns (PAMPs), through Pattern Recognition Receptors (PRRs). The innate immune response aims to contain and eliminate pathogens until the adaptive immune response can be activated.

Antigen processing and presentation are crucial steps in the immune response, enabling the immune system to recognize and respond to foreign substances, such as pathogens or abnormal cells. These processes involve the presentation of antigens, which are small parts of foreign proteins, to immune cells called T lymphocytes (T cells). Antigens can enter the body through various routes, such as ingestion, inhalation, or through wounds. Antigen-presenting cells (APCs), primarily dendritic cells, macrophages and B cells, are responsible for capturing antigens. They have specialized receptors, such as Pattern Recognition Receptors (PRRs), which can recognize pathogen-associated molecular patterns (PAMPs) present on pathogens. Once captured, the antigens undergo processing within the APCs.