Immunology intro flash cards 1/6

Immunology

Study of a host's reactions to foreign substances

Antigens

Foreign substances that induce a host response• Examples: pollen proteins, components of bacterial pathogens

Immunity

condition of being resistant to infection

Attenuation

Pathogens made less virulent through heat, aging, or chemical treatment

Examples of attenuated vaccines

chickenpox, smallpox, MMR, yellow fever

Innate Immunity

Natural immunity, ability to resist infection through normally present body functions, Nonspecific, Prior exposure not required, effect is immediate, memory not generated

Adaptive Immunity

Characterized by specificity for each antigen, memory is generated

Where are leukocytes found, and name all types

Found in peripheral blood

• Neutrophils• Eosinophils• Basophils• Monocytes• Lymphocytes

Where do all WBC originate from?

HSC in the bone marrow

What precursors does HSC give rise to?

Common Myeloid Precursors (CMP) and Common Lymphoid Precursors (CLP)

CMP's develop into WBC's that perform______

Phagocytosis

CLP's develop into _______

Lymphocytes

Does dendritic cell come from CMP or CLP?

Both common myeloid and lymphoid precursors

Name Cells of Innate Immune System

PMNs, Monocytes, Macrophages, Mast cells, Dendritic cells.

What are the Polymorphonuclear cells (PMNs) and what does PMNs means?

Neutrophils, Eosinophils, and Basophils

Multi-lobed and granular cytoplasm

What are the tissue cells of the innate immune system ?

• Macrophages• Mast cells• Dendritic cells

What compromises 50-70% of WBC in peripheral blood?

Neutrophils

What is the primary function of Neutrophils

Phagocytosis and destruction of foreign particles

What are the nucleus and granules like for neutrophils?

Multi-lobed nucleus and neutral staining granules in cytoplasm

What compromises 1-4% of WBC in peripheral blood

Eosinophils

What are the functions of eosinophils?

• Phagocytosis

• Neutralization of products released in allergic reactions

• Killing of parasites

• Release of cytokines

What are the nucleus and granules like for eosinophils?

Contain a bilobed or ellipsoidal nucleus and red-orange cytoplasmic granules

What is the least abundant WBC

Basophils

What are the functions of basophils?

Release histamine and other granular contents, which induce and maintain allergic reactions

What are the nucleus and granules like for basophils?

Contain a bilobed nucleus and deep blue-purple cytoplasmic granules

What compromises 2-10% of circulating WBC

Monocytes

Where are Monocytes located?

Peripheral blood

What is a macrophage?

Originate from monocytes that have migrated to the tissues

What are the nucleus and granules like for monocytes ( and macrophages) ?

Large cells with a horseshoe-shaped nucleus, dull grayish blue cytoplasm ,and fine granules

What are the Macrophages innate immune functions?

• Phagocytosis and microbial killing

• Anti-tumor cell activity

• Intracellular parasite eradication

• Secretion of cell mediators

What are the Macrophages adaptive immune functions?

• Process and present antigens to T cells

• Produce cytokines that regulate immune responses

What do Mast Cells resemble ?

Basophils, but come from a different lineage

Where is Mast Cells present and what are the functions?

Tissues

Induce and maintain allergic reaction

Is dendritic cell adaptive or innate immunity?

Both adaptive and innate immunity

What is the most potent phagocytic cell

Dendritic cell

What is the most effective antigen presenting cell?

Dendritic cell

What are the cells of adaptive immune system

Lymphocytes

What represents 20-40% of circulating WBC

Lymphocytes

What are the types of Lymphocytes

T cells, B cells, NK cells

What are the nucleus and granules like for lymphocytes?

Small cells with a large, round nucleus, and sparse, light blue cytoplasm

Where do B cells mature?

Bone Marrow

When do B cells differentiate into plasma cells?

After contacting antigen

Where do T cells mature?

Thymus and all are CD3+

What do plasma cells secrete?

Antibodies (immunoglobulins)

What are the different subtypes of T Cells and Functions?

Helper T (CD4+)- produce cytokines that stimulate B cells in antibody production, and assist other T cells in cell mediated immunity

Regulatory T cells(CD4+) - inhibit immune response ( helps prevent auto-immune disease)

Cytotoxic T cells(CD8+) - destroy tumor cells and virus infected cells

What is a major type of innate immune cell (ILC) ?

NK cell

What are the features and functions of NK cells?

Large cells with kidney shaped nuclei and granular cytoplasm

Kill virus infected cells and tumor cells without needing prior exposure

Destroys antibody coated target cell

Positive for CD16 and CD56

What are the primary lymphoid organs?

Bone marrow and Thymus

What are the secondary lymphoid organs?

• Spleen

• Lymph nodes

• Mucosal associated lymphoid tissue (MALT)

• Cutaneous associated lymphoid tissue (CALT)

What do the secondary lymphoid organs function as?

Sites for contact with foreign antigens

What is the largest secondary lymphoid organ and what pulps does it have ?

Spleen has white pulp and red pulp

What is the red pulp

Rich with macrophages and destroys old RBC

What is white pulp?

• 20% total weight of spleen

• Contains lymphoid tissue arranged around arterioles in a periarteriolar lymphoid sheath containing T cells

• B cells are in follicles attached to the sheath

Where are lymph nodes located and what do they do ?

• Along lymphatic ducts, especially near joints and where arms and legs join the body

• Collect lymph from adjacent tissues

Where do lymphocytes and foreign antigens enter

Via afferent lymphatic vessels

Where are B lymphocytes and T cells located in a lymph node

• B lymphocytes are located in follicles within cortex

• T cells are mainly in the paracortex

Where is MALT found?

• Found on mucosal surfaces of the gastrointestinal, respiratory, and urogenital tracks

CALT is for ?

T cells, monocytes, macrophages, and dendritic cells found on skin