Definitions 2 Flashcards
What is opsonization?
The coating of pathogens with antibodies to mark them for destruction.
What is opsonin?
Antibody or other substance that binds to microorganisms making them susceptible to phagocytosis.
What is phagocytosis?
A process by which WBCs (phagocytes) engulf and digest cells.
What is a phagosome?
A vesicle formed around a particle engulfed by a phagocyte.
What is a phagolysosome?
A cytoplasmic body formed by the fusion of a phagosome with a lysosome.
What is C5a?
A strong chemoattractant that is involved in the recruitment of inflammatory cells (neutrophils, T cells, etc) and activate phagocytic cells.
What is C3b?
An opsonin; binds the membrane of pathogenic cells and then coats them with antibodies.
What is MAC?
The effector cells that forms pores in the plasma membrane of pathogens/targeted cells, leading to osmolysis.
What is chemotaxis?
Movement of a motile cell in a direction corresponding to a gradient of increasing or decreasing concentration of a particular substance.
What is selectin?
Part of a family of adhesion molecules that enable the initial attachment of a leukocyte from the bloodstream.
What is integrin?
Glycoproteins on cell surfaces that are involved in the adhesion of cells.
What are pattern recognition receptors (PRRs)?
Proteins capable of recognizing molecules frequently found in pathogens (PAMPs), or molecules released by damaged cells (DAMPs).
What is a pathogen associated molecular pattern (PAMP)?
Highly conserved structural motifs that are recognized by Pathogen Recognition receptors (PRRs) to initiate immune response.
What are acute phase proteins?
Produced in the liver in response to inflammatory cytokines. They increase inflammatory states.
What are Kupffer cells?
Resident liver macrophages; play a critical role in maintaining liver functions. They are the first innate immune cells and protect the liver from bacterial infections.
What is an osteoclast?
Cells that degrade bone to initiate normal bone remodeling and mediate bone loss in pathologic conditions.
What is a pulmonary alveolar macrophage?
Most abundant innate immune cells in the distal lung parenchyma. They’re the first to encounter incoming pathogens and help initiate the immune response in the lungs.
What is Fc?
Specific receptors for antibodies; they are proteins found on the surface of leukocytes.
What is Fab?
Fragment antigen-binding region; a region on an antibody that binds to antigens.
What is an antigen-binding site (ABS)?
The hypervariable site at the tip of each arm of the antibody molecule that is the binding site for antigen.
What is hapten?
A small molecule, when combined with a larger carrier (like a protein), can elicit the production of antibodies which bind specifically to it.
What is anti-immunoglobulin?
A type of secondary antibodies (protein molecules) that are able to detect primary antibodies and bind immunoglobulins.
