M20 LEC 6 - Overview of Host Immune Response

Neutrophil

The nosy one

Macrophage

The hungry one

Dendritic cells

The spy

Neutrophil

The ninja

Immunis

Where the word "immune" came from and means "exempted"

Immunology

Study of immune systems in all organisms

Autoimmune system

The immune system fights the cells or some cells of the body causing autoimmune diseases like systemic lupus, cytokine storm, some forms of arthritis, and erythematosus

Hematopoiesis

Formation and development of blood cells

Haima

This means "blood"

Poiein

This means "to form/make"

Bone marrow

Where hematopoiesis occurs from birth throughout lifetime

True

There is little amount of hematopoiesis in the lymph nodes

1 billion to 1 trillion

Healthy adult persons produce new blood cells a day at this number

Pluripotent stem cell

Where all different types of blood cells come from

55%

Percent of plasma in the human blood

45%

Percent of cellular elements in the human blood

95%

Percent of erythrocytes in the cellular elements in the human blood

Myeloid lineage

The cells belonging to _______ _______ are involved in the innate immune response; some cells here are also involved in the transport of gas and clotting

Lymphoid lineage

Most of the cells of the _______ _______ are responsible for adaptive/acquired immune response

Granulocytic

Type of stem cell that gives rise to eosinophils, basophils, and neutrophils

Lymphocytic

Type of stem cell that gives rise to natural killer cell, T cell, and B cell

10 trillion

Average number of lymphocytes in the human body

Lymphocytes

Continuously circulates in the lymph and blood and migrates in tissue spaces and lymphoid organs; small cells that have slightly visible cytoplasm around a single nucleus

Natural killer cells

5-10% of the lymphocytes that circulates the body; large non-phagocytic lymphocytes that are capable of killing abnormal host cells

Cytotoxic

Natural killer cells are considered functionally _______ because they kill cells that are infected with viruses or tumors

False

T or F: Natural killer cells need to recognize antigens presented on the target cell

Perforin

This chemical perforates the surface of the cell and damages the target cell's membrane, resulting in its death

Granzyme

This chemical is an apoptosis inducer and is triggered by a healthy normal process in the body

FS (CD95)

This chemical is also involved in programmed cell death other than granzyme

B lymphocytes (B cells)

Described as bone marrow residents that have hair-like projections on their surfaces; synthesizes immunoglobulin molecules

Plasma cells & memory cells

Two types of B cells that arise when these B cells mature

Bursa of Fabricius

A lymphoid organ in birds where B cells were first discovered

Plasma cell

This type of mature B cell is the factory for antibodies

True

T or F: Plasma cells have a large cytosol and a small nucleus

2-3 hours

Lifespan of plasma cells in vivo

T lymphocytes (T cells)

Cells of the lymphoid lineage that migrate to and differentiate in the thymus

Help B cells produce antibodies; regulate the immune response

Two functions of T cells

Bone marrow

Origin of T cell

Bone marrow

Origin of B cell

Thymus

Where T cells mature

Bone marrow; Peyer's patches

Where B cells mature

Monocytes

Mononuclear cells that circulates in the blood

Macrophage

The term used to refer to monocytes once they become tissue residents

Antigen processing and presentation, T cell activation, phagocytosis

Function of monocytes and macrophages

Endothelium

After 1 to 2 days of staying in circulation, monocytes cross the _______ to enter tissues and become macrophages

8.4 hours

Half-life of monocytes

True

T or F: The nucleus of the macrophage is slightly bigger than the nucleus of the monocyte

Pseudopodia

Projections of macrophages that become more pronounced when monocytes become macrophages

True

T or F: Phagolysosomes are only found in macrophages

Osteoclast

Type of macrophage from monocyte that resides in the bone

Alveolar macrophage

Type of macrophage from monocyte that resides in the lung

Kupffer cell

Type of macrophage from monocyte that resides in the liver

Histiocyte

Type of macrophage from monocyte that resides in connective tissues

Microglia

Type of macrophage from monocyte that resides in the brain

Portals of entry

Dendritic cells are found throughout the body, but especially in _______ ___ _______

Dendritic cells

Actively engulf cells and foreign particles in their environment

Innate

Type of immunity that dendritic cells play an importance in

T cell activation, antigen/foreign body transport to lymph nodes, antigen presentation, manipulation

4 functions of dendritic cells

Langerhans cells

Type of dendritic cell found in the skin

Circulating dendritic cell

Type of dendritic cell found in myeloid and plasmacytoid

Interstitial dendritic cell

Type of dendritic cell found in lungs, liver, intestines, and the heart

Interdigitating dendritic cell (Tip: interdigi"T" -> T cell areas and thymic)

Type of dendritic cell found in T cell areas of lymph nodes and the thymic medulla

Granular leukocytes

White blood cells that contain cytoplasmic granules; frontliners during the immune response

Amines

This component of basophils can be stained by basic dyes

Basic proteins

This component of eosinophils can be stained by acidophilic or eosinophilic dyes

Basic proteins and amines

This component of neutrophils can be stained by neutral staining

Eosinophil

What type of granular leukocyte is shown in the picture?

60%

Neutrophils comprise this percent of the peripheral blood leukocytes

Polymorphonuclear

Neutrophils are also known as _______

2 to 5

Number of segments of the nucleus in neutrophils

7 hours

Half-life of neutrophils

Phagocytosis

Main function of neutrophils

Acute infection

If there is an excessive number of neutrophils in the body, this is indicated

Juvenile forms and metamyelocytes

When reserves of the segmented neutrophils in the bone marrow are depleted, the number of these two increase in circulation

Lactoferrin & lysozyme

Direct microbial agents that are produced by neutrophils

Leukotrienes & prostaglandins

Mediates vascular functions and are produced by neutrophils

Myeloperoxidase

Supports oxidized antimicrobial functions and are produced by neutrophils

Bilobed

Basophils and mast cells are this type of cell based on the number of their lobes

Vasoactive amines

Once basophils and mast cells granulate, they release these and are associated with an allergic reaction

Mast cells

Tissue resident forms of basophils

Fc receptors of IgE

Mast cells contain these receptors

Type 1

Type of hypersensitivity response associated with allergic reactions

Bilobed

Eosinophils are this type of cell based on the number of their lobes

Participate in parasitic infections, secrete cytokines, involved in allergic reactions and inflammation

3 functions of eosinophils

Initial barrier

Immune system's protection from microbial invasion that is usually composed of mechanical, chemical, and biological barrier

Innate immune system

Immune system's protection from microbial invasion that performs when the barriers are compromised; antigen non-specific; e.g. epithelial cells, phagocytic cells, dendritic cells, cytokine

Adaptive immune system

Immune system's protection from microbial invasion that supports the innate immune system in defending from microbes; antigen-specific

Humoral immunity

Principle defense mechanism against extracellular microbes and their toxins; mediated by antibodies produced by B lymphocytes

Cell-mediated or cellular immunity

Defense against intracellular microbes such as viruses and some bacteria; mediated by T lymphocytes

Toll-like receptor 9

Polices the host cells; once antigens infiltrate the body, these receptors monitor and reports them, alerting the immune response of the presence of these foreign bodies

Skin

Inhospitable to microbes

Stratum corneum

Outermost epidermal layer and the cells of this layer provides a water-tight barrier, preventing dehydration

Epithelium

Lines the body's cavities that are in contact with the environment

Cilia of the epithelial lining

Aids in cleaning the respiratory tract by expelling the secretions with trapped microbes and particles outward through sneezing and coughing

Urination

Helps in inhibiting movement of microbes from the environment into the bladder and kidneys

Catheter

If an individual has this and is placed in the body for a long time, the protective mechanism of urination may be disrupted or compromised

Acidic secretions of the vagina; microcidal molecules

The female urogenital tract is important as it contains or is protected by these that are secreted by the mucous membranes

~5

pH of the skin

1.0 to 3.0

Normal pH of the stomach

4.4 to 4.6

Normal pH of the vagina