Immunobio cumulative for exam 1

What is immunology

The study of the cells, tissues, genes, and proteins that mediate immunity

what does immunity mean

Protection from harmful threats, meaning to be exempt from

What is homeostasis

the body’s natural state of balance among organs and body systems

What happens when homeostasis is disturbed

the immune system responds to store balance

What can disturb homeostasis

trauma, pathogens, cancer, damaged cells, or disregulated body cells

What is the simplest immune response

identifying and cleaning damaged or dying cells from the body

What is a pathogen

a disease causing organism or infectious agent

what is infection

the attachment and entry of a pathogen into the host

What are extracellular pathogens

pathogens that do not need to enter host cells to reproduce

Give examples of extracellular pathogens

some bacteria, most parasites, and fungi

What are intracellular pathogens

pathogens that must enter a host cell to reproduce

give examples of intracellular pathogens

viruses, some bacteria and a few parasites

What is cell-mediated immunity

immunity that depends on immune cells destroying or removing unwanted material

What is humoral immunity

immunity that depends on soluble molecules in blood serum, especially antibodies

what are leukocytes

white blood cells involved in immune responses

What are cytokines

signaling molecules used by immune cells to communicate

What are the two major types of immune responses

innate immunity and adaptive immunity

What is innate immunity

The immediate, broad immune response that uses pattern recognition and has no strong memory

What is adaptive immunity

a delayed, specific immune response that uses antigen receptors and forms memory

What triggers the innate immune system

recognition of PAMPs and DAMPs by pattern recognition receptors

What are PAMPs

pathogen associated molecular patterns found on or produced by pathogens

What are DAMPs

damage associated molecular patterns realized by damaged or abnormal body cells

What are PRRs

pattern recognition receptors that detect DAMPs and PAMPs

What are major characteristics of adaptive immunity

specificity, division of labor, memory, diversity and tolerance

What is immunological memory important

it allows faster, stronger response after repeat exposure to the same pathogen

Who is Edward Jenner associated with

early vaccination work using cowpox exposure to protect against smallpox

What observation did Kenner make

milkmaids exposed to cowpox seemed protected from smallpox

What helped establish immunology as a field

Louis Pasteur

What is an attenuated pathogen

a weakened pathogen used to stimulate immunity without causing severe disease

What experiment is Pasteur known for

the sheep anthrax experiment using attenuated pathogens

What disease did Pasteur treat with an attenuated virus

rabies

Where does the word vaccination come from

from the word vacca meaning cow, because of cowpox

what are barrier defenses

physical and chemical defenses that prevent pathogen entry

Give examples of barrier defenses

skin, stomach acid, tears, vaginal lactic acid

What is complement

a system of inactive blood enzymes that can become activated to help fight pathogens

What is phagocytosis

the engulfing and digestion of unwanted particles or pathogens by immune cells

What cells mainly preform phagocytosis

neutrophils, microphages and dendritic cells

what are phagocytes

immune cells that engulf and digest pathogens or debris

what happens after PRRs are engaged

pro inflammatory cytokines are produced

What is inflammation

local gathering of immune cells and molecules to repair damage and clear pathogens

What is target cell lysis

the destruction or bursting of abnormal, infected, or cancerous cells

Which cells can lyse target cells

neutrophils, macrophages and natural killer cells

What cells are involved in adaptive immunity

lymphocytes, especially B and T cells

What are B cells mainly known for

producing antibodies and participating in humoral immunity

What are T cells mainly known for

coordinating immune responses or killing infected cells

What determines adaptive immune specificity

antigen receptors on B cells and T cells

What is BCR

B cell receptor, the antigen receptor found on B lymphocytes

What is TCR

T cell receptor, the antigen receptor found on T lymphocytes

What is an antigen

a molecule or molecular shape recognized by immune receptors

What is clonal selection

only lymphocytes with receptors specific to an antigen are activated and expanded

What is somatic recombination

random rearrangement of gene segments to create diverse lymphocyte receptors

Why does adaptive immunity have diversity

somatic recombination creates many unique BCRs and TCRs

what is tolerance

the immune system’s ability to avoid attacking self antigens

What is central tolerance

elimination of self reactive lymphocytes early in development

What is peripheral tolerance

silencing self reactive lymphocytes that escaped central tolerance

What is priory immunodeficiency

A genetic defect someone is born with that weakens immune function

What is acquired Immunodeficiency

immune weakness caused by an external factor, such as pathogen or nutrition issue

What is transplant rejection

immune attack against foreign transplanted tissue

What is autoimmune disease

disease caused by immune attack against the body’s own tissue

What is hypersensitivity

an immune response that is too strong, too long, or innapropriate

what is allergy

a hypersensitivity response to a generally harmless antigen

What is chronic inflammation

inflammation that does not resolve and may contribute to disease

What disease can chronic inflammation contribute to

tummors, heart disease, and autoimmune disease

How do innate and adaptive immunity interact

innate immunity starts the response and can active adaptive immunity

What is the immune systems ultimately trying to maintain

balance, homeostasis

What is hematopoiesis

The generation of all red and white blood cells

What type of stem cell gives rise to all blood cells

Hematopoietic stem cells, or HSCs

What are the two major lineages from HSCs

Myeloid lineage and lymphoid lineage

Where does hematopoiesis occur in adults

mainly in the axial skeleton: sternum, ribs, vertebrae, pelvis, and skull

What are granulocytes

immune cells with intracellular granules

What myeloid cells are granulocytes

neutrophils, basophils, and eosinophils

What immune system branch are myeloid cells mostly part of

the innate immune system

What are neutrophils

the most abundant leukocytes in circulation and early responders to inflammation

What are the main functions of neutrophils

phagocytosis and degranulation

What are basophils best known for

degranulation and sustaining the inflammatory response

What are the eosinophils important for

killing large parasites using proteins and enzymes on their granules

What are monocytes

large circulating leukocytes that patrol blood and can enter tissues

What can monocytes differentiate into

macrophages or dendritic cells

What is the main role of monocytes

Phagocytosis and cytokine secretion

What are microphages

Large tissue-resident phagocytes that engulf pathogens and dead cells

What are Kupffer cells

macrophages found in the liver

What are osteoclasts

macrophage-like cells found in bone

What are lymphocytes

cells of the lymphoid lineage involved mainly in adaptive immunity

What are the main adaptive immune lymphocytes

B and T cells

What are CD markers

surface proteins used to identify immune cell types

What does CD4 identify

Helper T cells

What does CD8 identify

Cytotoxic T cells

What is the main function of CD4+ T cells

cytokine secretion and helping coordinate immune responses

What is the main function of CD8+ T cells

cytolysis of target cells and cytokine secretion

What do mature B cells express

B cell receptors or BCRs and markers like CD19 and CD21

What does a plasma cell do

secretes antibodies that bind antigens and mark them for destruction

What is lymphocyte priming

activation of a lymphocyte after it binds its specific antigen

What are lymphoblasts

activated lymphocyte progeny formed after antigen recognition and cell division

What do lymphoblasts differentiate into

short lived effector cells and long lived memory cells

What is a cytotoxic T lymphocyte or CTL

An effector CD8+ T cell that kills target cells

What do helper T cell effector cells do

Secrete large amounts of cytokines to support B cell and Tc responses

What are natural killer cells

Lymphoid cells that kill virus infected and tumor cells

How are NK cells different from cytotoxic T cells

NK cells are less specific and do not require the same antigen specificity as CTLs

What receptors allow NK cells to kill antibody coated cells

Fc receptors, or FcRs

What does an Fc receptor bind

the Fc regions of antibodies