Introduction to Immunity
Foreign substances that induce a host response.
What are antigens?
Composed of physical, chemical, and biological barriers that function together to prevent infectious agents from entering the body.
What is the external defense system?
Include PRRs, acute phase reactants, inflammation, phagocytic cells, NK cells, and innate lymphoid cells.
What is the internal defense system?
This MHC molecule contains one alpha chain and one beta 2-microglobulin.
What is a class I MHC molecule?
Age, overall health, dose, genetic capacity, and route of inoculation.
What are the factors that influence the immune response?
The ability to resist infection through normally present body functions.
What is innate immunity?
Found on phagocytic cells, these receptors are able to distinguish pathogens from normally present molecules in the body.
What are pattern recognition receptors?
Levels of this acute-phase reactant rise within 4-6 hours of stimulus, are capable of opsonization and complement activation, and increased levels are a significant risk for heart disease.
What is C-Reactive protein (CRP)?
Substances delivered simultaneously with an antigen to enhance the immune response.
What is an adjuvant?
Part of the antigen/immunogen that is recognized by lymphocytes. Can be linear or conformational.
What is an epitope?
Characterized by specificity for each antigen. Memory is generated.
What is adaptive immunity?
Recognize by PRRs, these are found only in microorganisms. They help distinguish self from non-self.
What are pathogen-associated molecular patterns (PAMPs)?
Proteins that form channels in the target cell membrane.
What are perforins?
Small substances that are nonimmunogenic by themselves, but create new antigenic determinants when combined with a carrier.
What are haptens?
Presents exogenous antigen to CD4+ T cells.
What are class II MHC molecules?
Polymorphonuclear cells (PMNs) - neutrophils, eosinophils, and basophils, monocytes, macrophages, mast cells, and dendritic cells.
What are the cells of the innate immune system?
These receptors are strategically located on and in dendritic cells, macrophages, and monocytes, and each one recognizes a different microbial product. Once these bind to their corresponding substance, immune host responses are initialized.
What are Toll-like receptors (TLRs)?
Adherence, engulfment, formation of phagosome, granule contact, formation of phagolysosome, digestion, and excretion.
What is the process of phagocytosis?
Presents endogenous antigen to CD8+ T cells.
What are class I MHC molecules?
Found on all nucleated cells, regions A, B, and C of chromosome 6 code for these.
What are class I MHC molecules?
The primary lymphoid organs.
What are the bone marrow and thymus?
Chemical mediators are released to increase blood flow to the area. Increased capillary permeability allows fluids to leak into the tissues. Migration of WBCs to the surrounding tissue through diapedesis. WBCs follow chemokines via chemotaxis to the site of infection.
What are the steps of inflammation?
Cells that develop from the common lymphoid progenitor cell, but do not express markers of the lymphoid lineage, are found mainly at mucosal sites and release immunoregulatory cytokines.
What are innate lymphoid cells (ILCs)?
This is required during the production of class II MHC molecules to prevent endogenous peptides within the endoplasmic reticulum from binding to the class II peptide-binding groove.
What is an invariant chain?
Antigens that exist in unrelated plants or animals, but are identical to or closely related in structure so that antibody to one antigen will cross-react with the other.
What is a heterophile antigen?