Antigens, antibodies t&B cells

• Antibody-mediated immunity is the second line of defense against pathogens.
• Innate response involves phagocytosis by macrophages and neutrophils, complement activation, inflammation, and cytokine production.
• The immune system has two types of responses to antigenic challenge: innate (non-specific) and adaptive (acquired).
• Adaptive response involves B lymphocytes producing specific antibodies that bind to antigens on microorganisms or their products.
• Humoral immunity refers to the production of antibodies by plasma cells derived from B cells.
• T helper cells activate cytotoxic T cells and other immune effector cells.
• Cellular immunity involves T lymphocytes recognizing foreign proteins presented as peptides bound to MHC molecules on the surface of infected host cells.
• T lymphocytes recognize foreign proteins presented as peptides bound to MHC molecules on APCs.
• Lymphocytes have receptors on their surface called antigen receptors, which recognize and respond to specific antigens.
• Cellular immunity involves cytotoxic T cells attacking infected host cells.
• T lymphocytes are involved in cellular immunity, while B lymphocytes produce antibodies that bind to foreign substances.
• Immunity can be passive or active.
• Cellular immunity involves the destruction of infected host cells by cytotoxic T cells.
• Antibody-mediated immunity is mediated by antibodies produced by B lymphocytes.
• Antibody-mediated immunity is mediated by humoral immunity involving B lymphocytes producing specific antibodies that bind to antigens on microorganisms or their products.
• Cell-mediated immunity is mediated by T lymphocytes recognizing foreign proteins presented as peptides bound to MHC molecules on the surface of infected host cells.
• Adaptive immunity develops over time and provides long-lasting protection against specific pathogens through the production of memory cells and antibodies.
• Innate immunity provides immediate protection against pathogens through physical barriers such as skin and mucous membranes, chemical defenses like stomach acid, and phagocytosis by macrophages and neutrophils.
• Active immunity occurs when the body produces its own antibody response against a pathogen.
• Antibody-mediated immunity is mediated by plasma cells producing antibodies against pathogens.
• Humoral immunity involves the production of antibodies by plasma cells derived from activated B lymphocytes.
• Adaptive immunity is specific and requires prior exposure to a particular pathogen.
• Adaptive immunity consists of cellular and humoral responses.
• The adaptive immune system has two main components: humoral (antibody) immunity and cell-mediated immunity.
• Adaptive immunity provides long-lasting protection against infectious agents through memory responses.
• Memory cells are produced during an immune response and can quickly respond to subsequent exposure to the same antigen.
• Memory cells are produced during adaptive immune responses and can quickly respond upon reexposure to the same antigen.
• T helper (Th) cells activate other immune cells and produce cytokines.
• T helper cells activate macrophages and cytotoxic T cells through cytokines such as interleukin-2 (IL-2).
• Cytotoxic T cells directly kill infected host cells.
• T helper cells play a crucial role in activating other immune cells such as cytotoxic T cells and B cells.
• Antibodies bind to specific antigens on microorganisms or their products, marking them for destruction by other cells.
• Antibodies are proteins that bind specifically to foreign substances called antigens.
• T cells recognize foreign proteins presented as peptides bound to MHC molecules on the surface of infected host cells.
• Cell-mediated immunity involves T cells that directly kill infected cells or activate macrophages to destroy intracellular parasites.
• Each arm of the "Y" contains variable regions that determine its binding site for a specific antigen.
• Antibodies are Y-shaped molecules made up of four polypeptide chains held together by disulfide bonds.
• Antibody-mediated immunity is initiated by B lymphocytes producing antibodies against pathogens or their products.
• white blood cells / leucocytes are involved in immunit
• cell-mediated immunity involves T-cells