VOCAB CLINICAL IMMUNOLOGY QUIZ 1

Hematopoietic stem cell

Stem cell that gives rise to all blood cells

Lymphoid lineage

Blood-cell lineage that gives rise to B cells, T cells, and other lymphoid cells

Myeloid lineage

Blood-cell lineage that gives rise to monocytes, macrophages, neutrophils, eosinophils, basophils, mast cells, and other myeloid cells

Erythroid lineage

Blood-cell lineage that produces red blood cells

B cell

Adaptive immune cell that recognizes antigens and can develop into plasma cells that can produce antibodies

Plasma cell

Differentiated B cell that produces and secretes antibodies

T cell

Adaptive immune cell involved in recognizing antigens and coordinating or carrying out cell-mediated immune responses

Dendritic cell

Immune cell that captures pathogens and presents antigen to T cells, connecting innate and adaptive immunity

Macrophage

Innate immune cell that engulfs and destroys pathogens and dead cells and releases cytokines

Monocyte

Innate immune cells that circulates in the blood and can enter tissues and become macrophages or dendritic cells

Neutrophil

Rapid-response innate immune cell that phagocytoses and destroys pathogens

Eosinophil

Innate immune cell that helps defend against parasites

Basophil

Innate immune cell that helps defend against parasites and may play a role in activating T-cells to combat parasitic infection

Mast cell

In connective tissue, secretes molecules that aid wound repair & blood vessel growth and releases histamine

Innate immunity

Immediate, nonspecific defense against pathogens

Adaptive immunity

Specific immune response that develops after exposure to an antigen

Humoral immunity

Adaptive immunity primarily involving B cells and antibodies

Cell-mediated immunity

Adaptive immunity primarily involving T cells

Antibody

Protein produced by plasma cells that specifically binds an antigen

Antigen

Substance recognized by the adaptive immune system that can trigger an immune response

Primary lymphoid tissue

Tissue where lymphocytes develop and mature

Bone marrow

Primary lymphoid tissue where blood cells are produced and B cells mature

Thymus

Primary lymphoid tissue where T cells develop and mature

Secondary lymphoid tissue

Tissue where immune cells encounter antigens and become activated

Lymph node

Secondary lymphoid tissue that filters lymph and is a site of antigen presentation and lymphocyte activation

Spleen

Secondary lymphoid tissue that filters blood and helps respond to bloodborne pathogens

MALT (mucosa-associated lymphoid tissue)

Secondary lymphoid tissue located at mucosal surfaces that helps respond to pathogens entering through mucosa

Primary lymphoid tissues

Bone marrow and thymus

Secondary lymphoid tissues

Lymph nodes, spleen, and MALT

Physical barrier

Physical defense that prevents pathogens from entering or helps remove them, such as skin, epithelial barriers, mucus, and tears

Chemical barrier

Chemical defense that inhibits or destroys pathogens, such as acidic pH, lysozyme, defensins, and complement

Biological barrier

Defense provided by normal microbiota that compete with pathogens and inhibit their growth

Microbiota

Microorganisms normally living on or in the body that can help prevent pathogen growth

Lysozyme

Enzyme that breaks down bacterial cell walls

Defensins

Antimicrobial proteins that can disrupt microbial membranes

Complement

Group of proteins that help recognize and destroy pathogens and promote inflammation

PAMP

A common molecular structure found on microbes that can be recognized by innate immune cells

PRR

Receptor that recognizes PAMPs on pathogens

PAMP–PRR recognition

Process in which a PRR recognizes a microbial PAMP, allowing an innate immune cell to detect the pathogen

Ligand

Molecule that binds to a specific receptor

Receptor

Protein that recognizes and binds a specific molecule or signal

Phagocytosis

Process in which a phagocyte engulfs and destroys a pathogen or other material

Phagocyte

Immune cell that can engulf and destroy pathogens, such as neutrophils and macrophages

Phagosome

Vesicle formed when a phagocyte engulfs a pathogen

Lysosome

Cell compartment containing enzymes and antimicrobial substances that help break down material

Phagolysosome

Structure formed when a phagosome fuses with a lysosome; the engulfed pathogen is destroyed here

Phagocytosis sequence

PAMP recognition → PRR binding → engulfment → phagosome formation → fusion with lysosome → phagolysosome → pathogen destruction

Pathogen destruction

Pathogens inside phagolysosomes are destroyed using low pH, digestive enzymes, and antimicrobial substances

Koch's Postulates

Four criteria used to establish a relationship between a microorganism and a specific disease

Koch's Postulate 1

The microorganism is found in abundance in organisms with the disease but not in healthy organisms

Koch's Postulate 2

The microorganism is isolated from the diseased organism and grown in pure culture

Koch's Postulate 3

The cultured microorganism causes the same disease when introduced into a healthy susceptible organism

Koch's Postulate 4

The same microorganism is isolated again from the newly diseased organism