Immunology Test 1

ABO blood groups (types),

A blood classification system based on the presence or absence of A and B antigens on red blood cells. The four major types are A B AB and O;

Acquired immunity

Immunity that develops during a person's lifetime through exposure to antigens or through the transfer of antibodies;

Active immunity,

Long-lasting immunity produced when a person's own immune system responds to an antigen and develops antibodies and memory cells;

Adaptive immune response,

A specific immune response carried out mainly by B cells and T cells that develops after exposure to an antigen and produces immunological memory;

Adenoids,

Masses of lymphoid tissue located behind the nasal cavity that help detect and respond to inhaled or swallowed pathogens;

Adrenal gland,

A gland located above each kidney that produces hormones including cortisol and adrenaline that influence stress responses metabolism and immune activity;

Adverse event,

Any unwanted medical occurrence that happens after a treatment or intervention whether or not the intervention caused it;

Adverse event (pertaining to vaccine),

Any health problem that occurs after vaccination whether or not the vaccine actually caused the problem;

Agglutination,

The clumping of cells or particles caused when antibodies bind to antigens on multiple cells at the same time;

Allele,

One of two or more alternative versions of a gene found at a particular location on a chromosome;

Allergen,

A normally harmless substance that triggers an allergic immune response in a sensitive person;

Allergy,

An exaggerated immune response to a normally harmless substance called an allergen;

Anemia,

A condition in which the blood has too few healthy red blood cells or too little hemoglobin to adequately carry oxygen;

Anergy,

A state in which an immune cell is alive but fails to respond to a particular antigen;

Antibody isotype,

A class of antibody based on the structure of its constant region. The major human isotypes are IgG IgM IgA IgE and IgD;

Antigen-presenting cell (APC),

An immune cell that processes antigens and displays antigen fragments on MHC molecules to activate T cells;

Antiserum,

Blood serum containing antibodies against a particular antigen that can provide passive immunity;

Anti-venom,

A preparation of antibodies used to neutralize toxins in venom after a bite or sting;

Artificial active immunity,

Immunity produced when vaccination exposes the immune system to an antigen and causes the person's own immune system to develop protection;

Autoantibody,

An antibody that mistakenly recognizes and binds to molecules from a person's own body;

Autoimmune disease

,A disease in which the immune system mistakenly attacks the body's own cells tissues or organs;

Autoimmune response,

An immune response directed against the body's own cells or molecules;

Bacterial modification enzyme (methylase),

An enzyme in a bacterial restriction-modification system that adds methyl groups to specific DNA sequences and protects bacterial DNA from its own restriction enzymes;

Bacteriophage,

A virus that infects and replicates within bacteria;

Basic reproduction number (R-naught or R0),

The average number of people one infected person is expected to infect in a completely susceptible population;

Basophil

A granulocyte that releases substances such as histamine and contributes to inflammation and allergic reactions;

BCR (B cell receptor),

An antigen-binding receptor on the surface of a B cell that allows the B cell to recognize a specific antigen;

Bifurcated needle,

A two-pronged needle designed to hold a small amount of vaccine and historically used to administer the smallpox vaccine;

Bone marrow,

Soft tissue inside bones where blood cells are produced and where B cells develop;

Booster (pertaining to a vaccine),

An additional vaccine dose given after the initial vaccination to strengthen or restore immune protection;

CDC (Centers for Disease Control and Prevention),

A United States public health agency responsible for monitoring preventing and responding to diseases and other health threats;

Chemokine,

A signaling protein that attracts and directs the movement of immune cells toward particular locations such as sites of infection;

Clonal anergy

,A state in which antigen-specific lymphocytes become functionally inactive instead of responding to an antigen;

Clonal expansion,

The rapid multiplication of a B cell or T cell after it recognizes its specific antigen;

Clotting factors (in blood),

Proteins in the blood that work together through a series of reactions to form a blood clot;

Coagulation

,The process through which blood forms a clot to reduce blood loss after a vessel is damaged;

Commensalism,

A biological relationship in which one organism benefits while the other is neither significantly helped nor harmed;

Coronavirus,

A member of a family of enveloped RNA viruses with spike-like surface proteins that can infect humans and other animals;

Cytokine,

A small signaling protein released by cells that helps control immune responses inflammation and communication between cells;

ELISA (enzyme-linked immunosorbent assay),

A laboratory test that uses antibodies and an enzyme-linked detection system to measure specific antibodies antigens or other molecules in a sample;

Eosinophil,

A granulocyte involved especially in defense against parasites and in allergic reactions;

Epithelial cells,

Cells that form protective layers covering body surfaces and lining organs and cavities. They provide an important physical barrier against pathogens;

Epitope,

The specific portion of an antigen that is recognized and bound by an antibody or immune receptor;

Eradication

The permanent worldwide reduction of a disease to zero cases so that continued transmission no longer occurs;

False negative

,A test result that incorrectly indicates that a condition or substance is absent when it is actually present;

False positive,

A test result that incorrectly indicates that a condition or substance is present when it is actually absent;

Fc portion of antibody

,The constant tail region of an antibody that interacts with immune cells and complement proteins rather than directly binding antigen;

Fc receptor

,A receptor on an immune cell that binds the Fc portion of antibodies and helps the cell respond to antibody-coated targets;

Fibrinolysis,

The process that breaks down a blood clot after a damaged blood vessel has been repaired;

Heat-killed vaccine,

A vaccine made using microbes that have been killed by heat so they cannot reproduce but can still stimulate an immune response;

Hematocrit,

The percentage of the total blood volume that is made up of red blood cells;

Hematopoiesis

,The process by which blood cells are produced and develop from hematopoietic stem cells;

Hematopoietic stem cell,

A stem cell mainly found in bone marrow that can develop into all major types of blood cells;

Hemolytic disease of the newborn,

A condition in which maternal antibodies cross the placenta and destroy fetal red blood cells because of incompatible blood antigens such as the Rh factor;

Hemostasis

,The overall process that stops bleeding after blood vessel damage through vessel constriction platelet plug formation and coagulation;

Homeostasis,

The maintenance of relatively stable internal conditions in the body despite changes inside or outside the body;

Human ACE2 receptor,

A cell-surface protein used normally in body functions that also serves as a receptor allowing SARS-CoV-2 to enter certain human cells;

Humoral immunity,

Adaptive immune protection primarily provided by antibodies produced by B cells and plasma cells;

Hybridoma,

A laboratory-created cell formed by fusing an antibody-producing B cell with a continuously dividing tumor cell to produce large amounts of one monoclonal antibody;

Immunodeficiency,

A condition in which part of the immune system is absent weakened or unable to function properly;

Immunogen,

A substance capable of stimulating an immune response;

Innate immune response,

The rapid nonspecific immune response present from birth that provides the body's first line of defense against pathogens;

Inoculation,

The introduction of a microorganism antigen or vaccine into an organism or culture;

Iron lung,A mechanical ventilator that uses changes in air pressure around the body to help a person breathe and was historically used for patients with paralytic polio;

Live viral vaccine

,A vaccine containing a living virus that has been weakened so that it stimulates immunity without normally causing disease;

Lymphoid lineage,

A developmental pathway from hematopoietic stem cells that produces lymphocytes including B cells T cells and natural killer cells;

Lysogen,

A bacterium carrying dormant bacteriophage DNA integrated into or maintained with its own genetic material;

Lytic phage cycle,

A bacteriophage replication cycle in which the phage reproduces inside a bacterium and eventually lyses the cell to release new viruses;

Megakaryocyte,

A large bone marrow cell that produces platelets by releasing fragments of its cytoplasm;

Modification site (in bacterial R/M system),

A specific DNA sequence recognized by a bacterial methylase and modified to protect the DNA from cleavage by the corresponding restriction enzyme;

mRNA vaccine,

A vaccine containing messenger RNA instructions that cause host cells to temporarily produce an antigen and stimulate an immune response;

Mutualism,

A biological relationship in which both organisms benefit;

Myeloid lineage,

A developmental pathway from hematopoietic stem cells that produces cells such as red blood cells platelets monocytes neutrophils eosinophils and basophils;

Naïve cell,

A mature B cell or T cell that has not yet encountered and responded to its specific antigen;

Natural active immunity,

Immunity produced when a person's own immune system responds to a natural infection and develops immune memory;

Opportunistic infection,

An infection caused by an organism that usually does not cause serious disease but can do so when a person's immune defenses are weakened;

Opsonin,

A molecule such as an antibody or complement protein that coats a pathogen and makes it easier for phagocytes to recognize and engulf;

Opsonization,

The process of coating a pathogen with molecules such as antibodies or complement proteins to make phagocytosis more efficient;

Opsonized

,Describes a pathogen or particle that has been coated with opsonins and marked for easier phagocytosis;

Palindromic DNA,

A DNA sequence that reads the same in the 5-prime to 3-prime direction on both complementary strands and is commonly recognized by restriction enzymes;

Pandemic of 1918,

A worldwide influenza pandemic beginning in 1918 caused by an H1N1 influenza A virus and responsible for extensive illness and death around the world;

Parasitism,

A biological relationship in which one organism benefits while harming the host organism;

Pathogenic,

Capable of causing disease;

Pathogenicity,

The ability of an organism or infectious agent to cause disease;

Patient zero (index case),

The first identified patient in an investigation of a disease outbreak. The identified case is not necessarily the first person who was actually infected;

Phage Dra proteins,

Proteins produced by certain bacteriophages that help protect phage genetic material from bacterial defense mechanisms such as restriction systems;

Phagolysosome,

A compartment formed when a phagosome containing an engulfed microbe fuses with a lysosome so the microbe can be destroyed;

Placenta,

A temporary organ connecting a developing fetus to the mother that allows exchange of nutrients gases and wastes and can transfer maternal antibodies to the fetus;

Polyclonal antibodies

,A mixture of antibodies produced by multiple B cell clones that recognize different epitopes on the same antigen;

Primary antibody (in an immunoassay),

An antibody that binds directly to the specific antigen being detected in an immunoassay;

Primary immune response,

The immune response that occurs the first time the body encounters a particular antigen and is generally slower and weaker than later responses;

Prophage,

Bacteriophage DNA that has become integrated into a bacterial chromosome or remains dormant within a bacterial cell during lysogeny;

Provirus,

Viral genetic material that has been integrated into the DNA of a host cell;

Pus,

A thick fluid containing dead and living immune cells microorganisms and cellular debris that can accumulate at sites of infection;

Recombinant protein vaccine,

A vaccine containing an antigenic protein produced using recombinant DNA technology rather than using the entire pathogen;

Restriction enzyme,

A bacterial enzyme that recognizes specific DNA sequences and cuts DNA at or near those sites;

Restriction site (in bacterial R/M system),

A specific DNA sequence recognized and cut by a restriction enzyme when the sequence is not properly protected by methylation;

Retrovirus,

An RNA virus that uses reverse transcriptase to make DNA from its RNA and can integrate that DNA into the host genome;

Rh factor,

A red blood cell surface antigen most commonly referring to the RhD antigen. People with the antigen are Rh positive and those without it are Rh negative;

Rh sensitization,

The development of anti-Rh antibodies in an Rh-negative person after exposure to Rh-positive red blood cells;