Exam 1: Cells of the Immune System Flashcards
Define Hematopoiesis
Physiological mechanism to produce RBC, WBC, and platelets
3 major lineages for hematopoiesis
- Erythroid - erythrocytes and platelets
- Myeloid - granulocytes, mast cells, monocytes, macrophages, myeloid dendritic cells
- Lymphoid - Lymphocytes (T and B cells)
Hematopoietic Growth Factors
- Colony stimulating factors (CSF) - granulocyte-monocyte CSF, Granulocyte CSF
- Interleukins (IL) - IL1, IL3, IL4, IL5, IL6, IL7
Neutrophils: description and location
First line of defense
Polymorphic nucleus - segmented, can have different shapes
Granular cytoplasm
Location: blood
Bird neutrophil is called heterophil
Eosinophils: Description and location
Eosinophilic granules - stain red with eosin
Location: blood and tissues lining gastrointestinal tract and airways
Monocytes: description and location
Second line of defense against pathogens
Important role in chronic infection
Large roundish nucleus
Diffuse pale blue-grey staining cytoplasm commonly containing vacuoles
Location: blood
Mast Cells: description and location
When mast cells activated - contents of granules released and induce inflammation
Round nucleus, cytoplasm densely packed with granules (purple)
Location: tissues - particularly connective tissue surrounding vasculature and nerves, lamina propria of mucosa
NK Cells: Description and location
Large lymphoid cell, round nucleus, azurophilic cytoplasm granules
Location: blood, spleen
Lymphocytes
Capable of specifically recognizing and distinguishing different antigens
Adaptive immune response, specificity, and memory
B cells (6 things)
Recognize extracellular antigens
Produce antibodies
Differentiate in plasma cells
Main role in humoral immune response
Mature in Bone marrow
In birds mature in the Bursa of fabricius
T cells (6 things)
Recognize intracellular antigens
Do not produce antibodies
Differentiate in several types of lymphocytes
Main role in cellular immune response
Mature in Thymus
Produce cytokines
Neutrophils: classification and lineage
Classification: granulocyte, phagocyte
Myeloid lineage
Neutrophils: Function
Antimicrobial effectors - particularly in acute bacterial infection
Neutrophils: Mechanism of action
Phagocytosis, degranulation, neutrophil extracellular trap formation
Eosinophils: Classification and lineage
Classification: granulocyte
Myeloid lineage
Eosinophils: Function
Anti-parasitic effectors - particularly in helminthic infection, some antiviral action, roles in allergy
Eosinophils: Mechanism of action
Degranulation, limited phagocytosis
Basophils: Description and location
Blue-purple basophilic granules with basic dyes
Location: blood
Basophils: Classification and lineage
Classification: granulocyte
Myeloid lineage
Basophils: function
Mediator of inflammation
Basophils: Mechanism of action
Degranulation
Monocytes: Classification and lineage
Classification: mononuclear phagocytes
Myeloid lineage
Monocytes: Function
Precursors of macrophages and DCs
Monocytes: Mechanism of action
Limited antimicrobial function in blood
Macrophages: Description and location
Round nucleus, clear-vacuolated cytoplasm, irregular cell shape
Location: peripheral tissue
Macrophages: Classification and lineage
Classification: mononuclear phagocyte, sentinel cell, antigen presenting cell
Myeloid lineage
Macrophages: Function
Immune surveillance, moderate antimicrobial capacity, limited antigen presentation
Macrophages: Mechanism of action
Detection of threats and release of inflammatory mediators, phagocytosis
Dendritic cells: Description and location
Professional antigen presenting cells
Round nucleus, clear cytoplasm, irregular shape with long branched projections (dendrites)
Location: tissues
Dendritic cells: Classification and lineage
Classification: mononuclear phagocyte, sentinel cell, antigen presenting cells
Myeloid lineage
Dendritic cells: Function
Immune surveillance, antigen processing and presentation
Dendritic cells: Mechanism of action
Detection of threats and release of inflammatory mediators, endocytosis and phagocytosis
Mast cells: Classification and lineage
Classification: sentinel cells
Myeloid lineage
Mast cells: Function
Immune surveillance, mediator and amplifier of inflammation and allergy
Mast cells: Mechanism of action
Detection of threats and release of inflammatory mediators via degranulation (vasoactive amines) or synthesis of lipid mediators and cytokines
NK cells: Classification and lineage
Classification: lymphocyte
Lymphoid lineage
NK cells: Function
Destruction of virally infected or abnormal host cells (including tumor cells)
NK cells: Mechanism of action
Recognition of virally infected cells or abnormal host cells and target release of cytotoxic granules
