Immunology Ch 1

parasitic organism

one that lives at the expense of its host, any organism that causes disease is a parasite

infection

state occurring when a parasite is growing and multiplying on or within a host, competing for natural resources

infectious disease

a change form a state of health as a result of an infection by a parasitic organism

pathogen

an infectious organism that causes disease

pathogenicity

the ability of a parasitic organism to cause a disease

primary pathogen

organism that causes disease in a healthy host by direct interaction

opportunistic pathogen/commensals

organism that is normally-free living or part of the hosts normal microbiota, but adopts a pathogenic role under certain circumstances

virulence

the degree or intensity of pathogenicity of an organism

exogenous infection

a pathogen breaches the host’s external defenses and enters sterile tissue

endogenous infection

normal microbiota enter sterile tissue

opportunistic infections

commensals take advantage of the a change in the body’s environment that favors the microbe

primary infections

occur in otherwise health bodies

secondary infections

occur in a body weakened by a primary infection

local diseases

restricted to a single area of the body

systemic diseases

diseases that spread to different organs and systems

three barriers to infection

mechanical, chemical, microbiological

mechanical barrier to infection usually involves:

flow of fluid

chemical barrier to infection usually involves:

lysozymes, acidic environments, and defensins

microbiological barrier to infection usually involves:

normal flora out-competing the pathogen

nonspecific immune response characteristics

general resistance mechanisms inherited as a part of the innate structure and function of each animal

lack immunological memory

causes inflammation at sites of infection

response occurs to same extent with each encounter

specific immune response characteristics

adds to the ongoing innate immune response

very slow to start

resists a particular foreign agent by the production of antibodies to specific antigens

improves of repeated exposure

recognition mechanisms of innate immunity

rapid response, fixed mechanism, limited number of specificities, constant during response

recognition mechanisms of adaptive immunity

slow response, variable mechanisms, numerous highly selective specificities, improves during response

hematopoietic stem cells

in the bone marrow, the stem cells all immune system cells with different functions derive from

serum

fluid part of the blood (after clotting, usually outside of the body) containing minerals, salts, proteins, etc

plasma

fluid part of the blood inside the body that contains clotting agents (blood has not clotted)

leukocytes

white blood cells produced in the bone marrow

neutrophils

leukocytes, essential blood phagocytes, first responders, kills microorganisms

basophils

leukocytes, function in inflammatory events and allergies, similar to mast cells, controls immune responses to parasites

eosinophils

leukocytes, contain toxic compounds to defend against multicellular parasites such as worms and fungi, kills anti-body coated parasite through release of toxic granule contents

granulocytes

type of leukocytes, contains neutrophils, eosinophils, and basophils/mast cells

agranulocytes

type of leukocytes contains monocytes, macrophages, and lymphocytes (B cells and T cells)

monocyte

leukocyte, blood phagocytes that mature into macrophages and dendritic cells in tissue

macrophage

largest phagocytes that ingest and kill foreign cells, engulf and degrade dead neutrophils and the bacteria they are carrying, activates T cells and initiates immune response

lymphocytes

leukocytes that move to the lymph nodes after maturation into T cells or B cells, involved in specific immune responses (acquired immunity)

natural killer cells

lymphocytes that destroy virus-infected and abnormal cells

T cells

lymphocytes that perform a number of specific cellular responses such as assisting B cells and killing foreign cells through cell-mediated immunity

B cells

lymphocytes that differentiate into plasma cells and form antibodies resulting in humoral immunity

plasma cell

fully differentiated form of B cell that secretes antibodies that then tag antigens in an immune response

dendritic cells

found in the skin and other portals of pathogen origin, involved in acquired immunity, phagocytose microorganisms and kill viruses by secreting interferon, mature cells migrate to blood stream or lymphatic system to interact with B cells and NK cells and present foreign antigens to T cells activating them

lymph

clear fluid surrounding tissue cells and filling intercellular spaces

primary lymphoid tissues

thymus and bone marrow

thymus

where T cells are developed

bone marrow

site of B-cell development and other lymphocytes

secondary lymphoid tissue

spleen and lymph nodes, initiates adaptive immunity

spleen function

contains cells that monitor and fight infectious microbes primarily in the blood, provides adaptive immunity to blood infections

lymph nodes functions and specialized types

contain phagocytes and lymphocytes

types: tonsils, adenoids, spleen, Peyer’s patches, and appendix

lymphocyte recirculation

lymphocytes leave the blood and enter through the fine capillaries in secondary lymphoid organs

in the lymph node, if the lymphocyte does not encounter a pathogen to which its cell-surface receptor binds if leaves through the efferent lymphatic vessel and returns to the blood at the left subclavian vein

efferent lymphatic vessel

the lymph node vessel that lymphocytes leave through to recirculate

afferent lymphatic vessel

the lymph node vessel that pathogen or infected cell enter into the lymph node

Skin-associated lymphoid tissue

uses langerhans cells, specialized dendritic cells that phagocytose antigens, then migrate to lymph nodes and activate T cells, which then interact with activated B cells to induce a humoral response

Mucosal-associated lymphoid tissue

many types including gut-associated and bronchial associated

operates by the action of M cells in the mucous membrane

M cells

in MALT, phagocytose antigens and transports it either to a pocket within containing B cells and macrophages or to lymphoid follicles containing B cells

Antigens

chemical substances capable of mobilizing the immune system and provoking an immune response. They are microbes or microbial parts

Hapten

a small organic molecule that is not itself an antigen but may become antigenic when bound to a larger carrier molecule

epitope/ antigenic determinant

the part of the antigen that stimulates immune system activity

Major histocompatability complex (MHC)

group of genes that encode three classes of proteins, only class I and II are involved in antigen presentation, called human leukocyte antigen complex (HLA) in humans

Class I and Class II MHC molecules

both fold into similar shapes, each having a deep groove into which a short peptide or other antigen fragment can bind

presence of a foreign peptide in this groove alert the immune system and activates T cells or macrophages

Class I MHC molecules

the foreign peptides are produced intracellularly by antigen processing in the proteosome, the class I MHC binds the foreign peptide and is then incorporated into the plasma membrane to be detected by Cytotoxic T cells (CD8 cells)

Class II MHC Molecules

endocytosis brings antigens into Antigen-presenting cells and produces fragments in phagolysosomes

these fragments combine with class II MHC and are delivered to cell surface where they are detected by T-helper cells (CD4 T cells)

Cluster of differentiation molecules (CDs)

functional cell surface proteins that are used to differentiate leukocyte subpopulations

Mature B-Cells

mature in the bone marrow and produce specific antibodies against foreign antigens

Mature T- cells

leave the bone marrow and migrate to the thymus where they mature

CD4 T Cells (T-helper Cells)

produce lymphokines that help or suppress activities of other immune cells, detect peptide-class II MHC complexes on the surface of antigen presenting cells

CD8 T cells (Cytotoxic T cells)

kill infected or injured cells, detect peptide-class I MHC complexes on the plasma membrane of antigen presenting cells

diversity of immunoglobulins and T-cell receptors is generated by

gene rearrangement/somatic recombination

surface immunoglobulin and B-cell receptors look very similar to

antibodies! and they look like little Ys

Naturally acquired active immunity

results from contracting the disease and recovering

artificial acquired active immunity

established by vaccination, you still make antibodies

naturally acquired passive immunity

comes from acquiring maternal antibodies

artificially acquired passive immunity

receiving antibodies produced in another human or animal

Examples of pathogens that cause human disease include:

 

viruses

bacteria

parasites (protozoans and worms)

All of the above are examples of pathogens that cause human disease.

fungi

All of the above

Examples of granulocytes include all of the following except:

 

basophil

 eosinophil.

 All of the above are examples of granulocytes.

 neutrophil

 monocyte

monocyte

Virulence is the degree or intensity of pathogenicity of an organism.

 

True

False

True

What are the two types of immune response against a pathogen?

 

Innate and Adaptive immunity

Innate and Circulatory immunity

Circulatory and Lymphatic systems

Adaptive and Lymphatic immunity

Innate and Adaptive Immunity

Which of the following in NOT a Leukocyte?

 

Eosinophil

 

Monocyte

 

Erythrocyte

 

Basophil

 

Lymphocyte

Erythrocyte

The primary lymphoid tissues are the thymus and bone marrow.

 

True

 

False

True

The spleen provides adaptive immunity to what type of infections?

 

Mucosal infections

 

Skin infections

 

Blood infections

 

Brain infections

 

None of these answers are correct

blood infections

Most secondary lymphoid tissue is associated with the......

 

Lungs

 

Gut

 

Skin

 

Heart

Gut

Innate immunity has long lasting immunological memory against a pathogen after it has encountered it.

 

True

 

False

False

According to our lysozyme lab, which microbes are the most susceptible to lysozyme activity?

 

Viruses

 

Gram Positive bacteria

 

Gram Positive viruses

 

Gram neutral bacteria

 

Gram Negative bacteria

gram positive bacteria

Another term for "nonspecific immunity" is "adaptive immunity."

 

True

 

False

False