Antibody Structure

What is the primary difference between the innate and adaptive emmune systems?

Innate immunity is the body's first line of defense against pathogens and is non-specific, meaning it doesn't adapt or change even after repeated exposure to the same pathogens. Adaptive immunity is a highly specialized system that uses T-cells and B-cells to recognize specific antigens and provides long-term immunological memory after an infection has been cleared, offering longer-lasting protection.

Which cells are considered part of the innate immune system?

The innate immune system includes various cells. Macrophages, derived from monocytes, ingest and destroy pathogens. Neutrophils, abundant white blood cells, respond first to infection sites. Dendritic cells link the innate and adaptive immune responses by presenting antigens. Natural Killer cells defend against viruses and certain cancer cells, recognizing and killing infected cells without prior exposure. Mast cells, in connective and mucosal tissues, defend against pathogens and contribute to inflammation and allergies. Basophils and eosinophils combat parasitic infections and play a role in allergies, with eosinophils able to directly kill parasites. Innate Lymphoid Cells, a newer discovery, rapidly respond to infections by releasing cytokines.

What are the key roles of T-cells and B-cells in cell-mediated and humoral immunity, respectively?

T-cells are pivotal for cell-mediated immunity, where they directly kill infected cells or help in regulating immune responses. B-cells, on the contrary, are involved in humoral immunity by producing antibodies that can neutralize pathogens outside of cells. This immune response is particularly effective against bacteria and viruses before these pathogens get a chance to invade cells.

How is immunological memory established in the adaptive immune system?

Immunological memory is a critical aspect of the adaptive immune system. Through a process of learning and remembering, the immune system forms immunological memory cells when exposed to a particular antigen for the first time. This leads to a stronger and quicker immune response to future encounters with the same antigen. This concept is the fundamental principle behind vaccinations.

What role does the complement system play within the innate emmune system?

The complement system is a part of the innate immune response and comprises a series of proteins that, when activated, can enhance the ability of antibodies and phagocytic cells to clear microbes and damaged cells, promote inflammation, or directly kill pathogens. This system thus complements the immune response, enhancing the ability to clear pathogens and initiating healing processes.

What is the role of cytokines and leukocytes in both the innate and adaptive immune systems?

Leukocytes, or white blood cells, are involved in both innate and adaptive immunity. They fulfill various roles, being responsible for ingesting pathogens (phagocytosis), killing infected cells, or producing antibodies. Cytokines, on the other hand, are a type of signaling molecules that play a crucial inter-cellular communication role in the immune response. They help in recruiting immune cells to sites of infection, driving cell growth, or regulating immune responses, among other functions.