p.4
Functions of Granulocytes and Monocytes
What is a primary function of mast cells?
Release inflammatory mediators during degranulation.
p.4
Cells of Myeloid Lineage in Immunity
What are the two types of monocytes?
Inflammatory monocytes and patrolling monocytes.
p.2
Barrier Mechanisms in Immune Defense
What is the function of intraepithelial T-lymphocytes?
To recognize and respond to a small number of common microbial structures.
p.2
Barrier Mechanisms in Immune Defense
What is the role of dermal dendritic cells?
To initiate protective responses against viruses involving helper T-cells and cytotoxic T-cells.
p.5
Dendritic Cells and Antigen Presentation
What is the primary function of dendritic cells?
To function as antigen presenting cells and link the innate and adaptive immune responses.
p.3
Barrier Mechanisms in Immune Defense
What are common features of skin and mucosal barriers?
They are populated by commensal organisms, contain innate and adaptive immune cells, and include mechanical and chemical barriers.
p.2
Barrier Mechanisms in Immune Defense
What are some examples of physical barriers in epithelial tissues?
Tight junctions, keratin, and mucus assisted by cilia and peristalsis.
p.1
Collaboration between Innate and Adaptive Immunity
What happens to B and T cells after activation in lymph nodes?
They migrate to the bloodstream and travel to areas of inflammation to help destroy remaining pathogens.
p.5
Cells of Myeloid Lineage in Immunity
What is the role of interferon gamma (IFNγ) released by NK cells?
It protects adjacent cells from viral infection and helps activate T-cell mediated immune responses.
p.4
Cells of Myeloid Lineage in Immunity
What type of granules do basophils have?
Blue-staining cytoplasmic granules.
p.4
Functions of Granulocytes and Monocytes
What is the role of histamine released by mast cells?
Increases blood vessel permeability and smooth muscle activity.
p.4
Role of Phagocytic Cells in Innate Immunity
How do macrophages recognize pathogens?
By recognizing microbial molecules and host molecules produced in response to infections.
p.2
Barrier Mechanisms in Immune Defense
What type of cells are Langerhans cells?
A type of dendritic cell involved in T-helper mediated immunity against skin pathogens.
p.4
Cells of Myeloid Lineage in Immunity
What is a key characteristic of eosinophils?
They have pink-staining cytoplasmic granules.
p.3
Barrier Mechanisms in Immune Defense
What happens when normal bacterial flora are disturbed by antibiotics?
Susceptibility to opportunistic infections, such as Candida and Clostridium, may increase.
p.4
Functions of Granulocytes and Monocytes
What do mast cells and basophils have in common?
Both have high-affinity plasma membrane receptors for IgE.
p.2
Barrier Mechanisms in Immune Defense
What role do defensins play in the immune system?
They have direct toxicity to a broad range of microorganisms and activate leukocytes.
p.5
Cells of Myeloid Lineage in Immunity
What type of cells are NK cells?
They are a type of innate lymphoid cell (ILC) that do not express antigen-specific receptors.
p.3
Barrier Mechanisms in Immune Defense
What role does mucus play in the respiratory tract?
It traps microbial particles, which are then removed by cilia movement, coughing, or sneezing.
p.3
Functions of Granulocytes and Monocytes
What is the primary function of neutrophils?
They are the principal cell type in acute inflammatory reactions and function as phagocytic cells.
p.4
Cells of Myeloid Lineage in Immunity
What are fixed macrophages?
Tissue-resident macrophages that arise early in life from embryonic cells.
p.1
Collaboration between Innate and Adaptive Immunity
Where does adaptive immunity initiate?
In secondary lymphoid structures, such as lymph nodes.
p.3
Barrier Mechanisms in Immune Defense
What specialized lymphoid tissues are associated with mucosal barriers?
Peyer patches in the small intestine and isolated lymphoid follicles.
p.1
Cells of Myeloid Lineage in Immunity
Which cells express the widest variety of PRRs?
Phagocytes and dendritic cells.
p.3
Cells of Myeloid Lineage in Immunity
What types of cells arise from myeloid progenitors?
Granulocytes (neutrophils, eosinophils, basophils, mast cells) and monocytes/macrophages.
p.2
Barrier Mechanisms in Immune Defense
What are the two types of barriers mentioned?
Skin and mucosal barriers.
p.2
Barrier Mechanisms in Immune Defense
How do commensal organisms contribute to skin immunity?
They provide protection together with physical and chemical barriers.
p.1
Damage-Associated Molecular Patterns (DAMPs)
What are Damage-Associated Molecular Patterns (DAMPs)?
Endogenous molecules produced by or released from damaged or dying cells.
p.5
Cells of Lymphoid Lineage
What are the characteristics of innate lymphoid cells (ILCs)?
They do not express antigen-specific receptors and have distinct granular cytoplasm.
p.5
Cells of Myeloid Lineage in Immunity
What type of cells release histamine?
Basophils and mast cells.
p.5
Dendritic Cells and Antigen Presentation
Where are dendritic cells strategically located?
In various tissues and can migrate to T cell zones of lymph nodes.
p.5
Cells of Myeloid Lineage in Immunity
How do NK cells recognize and kill tumor cells?
By detecting decreased or absent MHC Class I expression on tumor cells and infected cells.
p.3
Functions of Granulocytes and Monocytes
What is the process of neutrophil extracellular trap (NET) formation?
It involves neutrophil activation, granule lysis, and the release of DNA and granule contents to immobilize and kill extracellular microbes.
p.1
Role of Phagocytic Cells in Innate Immunity
What role do resident phagocytic cells play in innate immunity?
They detect pathogens and release antimicrobial compounds and cytokines to recruit other immune cells.
p.1
Pathogen-Associated Molecular Patterns (PAMPs)
What are Pathogen-Associated Molecular Patterns (PAMPs)?
Molecular structures produced by microbial pathogens that are essential for their survival.
p.3
Barrier Mechanisms in Immune Defense
What are some mechanical factors that provide protection in the body?
Washing action of tears, saliva, and urine, along with secreted body fluids containing bactericidal components.
p.4
Role of Phagocytic Cells in Innate Immunity
What is the primary function of macrophages?
Expert phagocytes that remove pathogens and cellular debris.
p.1
Pathogen Entry and Detection
How do pathogens enter the body?
Through mucosal surfaces or breaches in the skin.
p.3
Barrier Mechanisms in Immune Defense
How do commensal organisms in the body protect against pathogens?
They compete effectively against many potential pathogens.
p.1
Pattern Recognition Receptors (PRRs)
What types of receptors are included in PRRs?
Toll-like receptors (TLR), mannose receptors, and scavenger receptors.
p.5
Functions of Granulocytes and Monocytes
What is the role of eosinophils in the immune system?
They are granulocytic cells important in the body's defense against parasitic organisms.
p.4
Role of Phagocytic Cells in Innate Immunity
What is one of the functions of macrophages in tissue repair?
Ingest necrotic host cells and promote angiogenesis.
p.2
Barrier Mechanisms in Immune Defense
What is the primary function of epithelial barriers?
To provide a physical barrier between microbes in the external environment and host tissue.
p.5
Dendritic Cells and Antigen Presentation
What happens to dendritic cells after they capture microbial antigens?
They transport the antigens to regional lymph nodes and mature.
p.2
Barrier Mechanisms in Immune Defense
What is Mucosal Associated Lymphoid Tissue (MALT)?
Barrier immunity associated with mucosal tissues that initiates immune responses to specific antigens.
p.1
Pattern Recognition Receptors (PRRs)
What is the function of Pattern Recognition Receptors (PRRs)?
They recognize PAMPs and DAMPs, activating signal transduction pathways to promote antimicrobial and proinflammatory functions.
p.3
Functions of Granulocytes and Monocytes
What is leukocytosis?
A transient increase in the number of circulating white blood cells during acute infection.
