4. Overview of Innate Immunity

What are the 3 general immune system barriers?

physical, chemical and mechanical

What are 5 immune system barriers?

epithelial barrier, mucus and microciliary clearance, commensal organisms, secretions, physical flushing

What are the 2 components of innate and adaptive immunity?

Humoral molecules, cells

What are 3 humoral molecules?

complement, acute-phase proteins, soluble pattern recognition receptors

List 3 types of innate immunity cells

mononuclear phagocytes, granulocytes, mast cells

What are the 2 hormonal molecules in adaptive immunity?

complement, immunoglobulins

What are the 3 adaptive immunity cells?

b and t lymphocytes, memory t cells

How do cytokines communicate?

signal proteins that are produced in response to stimuli and control the immune responses

What are interleukins?

cytokines that signal between lymphocytes and other leukocytes

What are interferons?

cytokines that are produced in response to virus infection or immune stimulation

What is tumor necrosis factor alpha?

a key mediator of acute inflammation which can also kill tumour cells

What are colony stimulating factors?

cytokines that control cell production by regulating stem cell activities

What are chemokines?

they play a role in leukocyte chemotaxis, circulation, and migration, especially in inflammation

Cytokines

Signalling proteins that are produced in response to stimuli and control the immune response

Phagocytosis

Absorption, phagolysosome formation and killing of bacteria

Degranulation

Release of granule contents into the extracellular space (proteases, lysozome etc.)

Neutrophil Extracellular Traps

When too large to eat, decondensation of chromatin and release of DNA along with granules into the extracellular space, bacteria killed

What are the two major arms of the immune response?

Innate and Adaptive immunity

What is the main difference in specificity between innate and adaptive immunity?

Innate is non-specific, while adaptive is highly specific

Which immune response develops immunological memory?

Adaptive immunity

What are PAMPs?

Pathogen-Associated Molecular Patterns, conserved structures on pathogens recognized by innate immune cells

What are DAMPs?

Damage-Associated Molecular Patterns, molecules released by damaged cells that trigger immune responses

What are PRRs?

Pattern Recognition Receptors, used by innate immune cells to detect PAMPs and DAMPs

Name three physical barriers in innate immunity

Skin, mucous membranes, and epithelial cells lining organs

What are the main cellular components of innate immunity?

Neutrophils, eosinophils, basophils, and NK cells

What is the primary function of neutrophils?

Phagocytosis of pathogens and release of antimicrobial substances

What unique defense mechanism do neutrophils employ against large pathogens?

Formation of Neutrophil Extracellular Traps (NETs)

What is the main role of eosinophils?

Combating parasites and contributing to allergic responses

What do basophils release during an immune response?

Histamine and cytokines

What is the primary function of Natural Killer (NK) cells?

Targeting and killing infected or cancerous cells

What are antigen-presenting cells (APCs) and their role?

Cells that process and present antigens to T cells, bridging innate and adaptive immunity

Name the three activation pathways of the complement system

Classical, lectin, and alternative pathways

What are the main functions of the complement system?

Opsonization, inflammation promotion, and membrane attack complex formation

What initiates the inflammatory response?

Recognition of PAMPs or DAMPs by PRRs

Name three pro-inflammatory cytokines

IL-1, TNF-alpha, and IL-6

What are the five cardinal signs of inflammation?

Redness, heat, swelling, pain, and loss of function

How do chemokines contribute to the immune response?

They guide the migration of immune cells to sites of infection or injury