Ch 16 Concepts of Inflammation and Immunity
Inflammation and Immunity
• Immunity – protection from illness or disease that is maintained by the body’s
physiologic defense mechanisms.
• Inflammation – a syndrome of normal tissue responses to cellular injury, allergy,
pathogen presence
• Microbiome – all microorganisms of normal flora that coexist in and on a person
Self vs Non-Self
The image above shows determination by immune system cell of self versus non-self cells.
Proteins on Human Cell Membranes
The image above labels proteins on human cell membranes: human leukocyte antigens (HLAs), individual recognition proteins (product
identification code), nonspecific human membrane proteins, receptors, tissue-specific membrane proteins, and plasma membrane.
Human Leukocyte Antigens
• Found on the surface of most body cells
• Unique surface protein specific to a person
• “Universal product code” for a person
• Key for recognition and self-tolerance
Organization of the Immune System
• Immune system
Present throughout the body; not confined to any single tissue or organ
• Stem cells
Immature, undifferentiated cells
Produced by bone marrow
• Leukocytes (WBCs)
Provide protection of the body
Immunity and the Older Adult
• Nutrition status, environmental conditions, drug, disease, and age change immunity
• Microbiome changes; overgrowth of more pathogenic organisms occurs
• Lower T-cell function
• B-lymphocytes take longer to become sensitized and begin to make antibodies to new
antigen exposures
• Circulating autoantibodies increases
Stem Cell Differentiation and Maturation
The image above details the process of stem cell differentiation and maturation.
Inflammation
• Innate–native immunity or natural immunity
• First line of protection
• Provides immediate protection against effects of tissue injury and foreign proteins
Infection
• Invasion of pathogens into the body
• Usually triggers inflammation
• Inflammation can occur without infection; infection usually triggers inflammation
Cell Types Involved in Inflammation
• Neutrophils
• Macrophages
• Basophils
• Eosinophils
• Tissue mast cells
Complement
• Composed of a system of 20 different types of inactive plasma proteins
• When activated, act as enzymes and attracting agents to enhance (complement) cell
actions of innate immunity
Phagocytosis
The image above shows the process of phagocytosis.
Five Cardinal Symptoms of Inflammation
• Warmth
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Redness
Swelling
Pain
Decreased function
Sequence of Inflammatory Responses
• Stage I (vascular)—change in blood vessels; redness and warmth
• Stage II (cellular exudate)—neutrophilia, pus
• Stage III (tissue repair and replacement) —WBCs trigger new blood vessel and growth
and scar tissue formation
Adaptive Immunity
• Also known as “acquired immunity”
• Protective response that is specific and results in long-term resistance to the effects of
invading microorganisms
Antibody-Mediated Immunity
Above image: antibody structure and the Fc receptors on leukocytes.
Antigen-Antibody Interactions
• Antigen recognition – recognition of antigen by unsensitized B-cells
• Sensitization – occurs when B-cell recognizes the antigen as non-self and is now
“sensitized” to this antigen
Agglutination
Image above show formation of large and small antigen—antibody complexes (immune complexes).
Antibody Classification
• All antibodies are immunoglobulins
• Five antibody types are classified by differences in size, location, amount, and function
Acquiring Antibody-Mediated Immunity
• Acquired immunity
• Active immunity
• Natural active immunity
• Artificial active immunity
• Passive immunity
• Artificial passive immunity
• Natural passive immunity
Cell-Mediated Immunity (CMI)
• Also called cellular immunity
• Involves many WBC actions and interactions
• For total or full immunity, CMI must function optimally
Protection Provided by CMI
• Helps protect body through ability to differentiate self from non-self
• Prevents development of cancer and metastasis after exposure to carcinogens