Chapter 1: Intro Flashcards
Immunity
State protection against foreign pathogens
Immune system
Collection of cells, tissues, and molecules which provide specific and non-specific protection against microbes, their toxins, and tumor cells
Pathogen
Microbe capable of causing disease
Infection
Ability of pathogen to enter host, multiply
Immunogen
Any substance that elicits an immune response
Epitope (determinant)
the part of an antigen that is specifically recognized by individual lymphocytes
Antigen
Any molecule that binds to immunoglobulin or a T cell receptor regardless of its ability to stimulate an immune response
Antibody (AB)
A type of glycoproteins (immunoglobulin) produced by B lymphocytes that binds antigen
Vaccine
A preparation of microbial antigen which is given to an individual to induce protective immunity
Immunoglobulin
Fraction of serum responsible for toxin neutralization/ precipitation (active molecules within are antibodies)
Antiserum
Blood serum that contains antibodies against a pathogen. Also includes antivenoms
Passive Immunity
Immune protection without having to produce antibodies
Natural: infants from mother
Unnatural: Antiserum injection after infection exposure
Active Immunity
Renewable long-lived protection from a specific infectious organism
Natural: after successfully fighting off many types of infection
Synthetic: Vaccines
T-lymphocytes
Cell-mediated immunity: develop and mature in the thymus
B-lymphocytes
Humoral immunity (produce antibodies) mature in the bone marrow
Cell-Mediated Immunity
Work of pathogen specific T-cells to directly eradicate infected cells and to aid in activating other immune cells
Clonal Selection
The receptor type of a B or T cell is selected before it comes in contact with antigen (highly random mutation). If its viable AND comes in contact with its matching antigen, it is ‘activated’ and will proliferate
Pathogen-Associated Molecular Patterns (PAMPs)
Common foreign structures that characterize whole groups of pathogens
Pattern recognition receptors (PRRs)
Expressed by white blood cells and specifically recognize common foreign structures (PAMPs) and help to activate innate immunity
Tolerance:
Ability of immune response to discriminate self from non-self. Failure to do so can lead to autoimmunity
Danger/ damage model of tolerance:
Seeing “other” without a ‘danger signal’ may not trigger immune response, while seeing ‘self’ WITH danger signals/ in the wrong context can break tolerance and trigger an immune response
Innate Immunity
Rapid recognition and phagocytosis/ pathogen destruction. Fast and non-specific
Complement
Pre-existing serum proteins to bind to PAMP structures and start immune cascade
Adaptive Immunity
More specific, but slower. uses B/T lymphocytes (takes 5-6 days after initial exposure to be up and running) Has memory, and is Immunity that is supported by vaccination
Sentinel cells
WBC which reside in specific tissues and act as local alarm systems and first responders.
Primary immunodeficiency
Caused by inherited genetic factors
Secondary immunodeficiency
Caused by disruption/ damage due to chemical, physical, or biological agents (starvation, HIV infection, cancer/ chemotherapy etc.)
Severe combined immunodeficiency (SCID)
Affects B/T cells, wiping out adaptive immunity. Will cause early death by infection if not treated with a bone marrow transplant
Dysbiosis (Gut Microbiome)
Causes immune overstimulation, leading to inflammation (gut barrier permeability, Gut-Brain-Immune system dysregulation) can lead to metabolic disruptions (T2D), Chronic inflammation (IBD), and neurological impacts (mood disorders)
Properties of adaptive immune response; specificity
Ensures that distinct antigens elicit specific responses
Properties of adaptive immune response; diversity
Enables immune system to respond to a large variety of antigens
Properties of adaptive immune response; memory
Leads to enhanced responses to repeated exposures to the same antigens
Properties of adaptive immune response; clonal expansion
Increases number of antigen-specific lymphocytes from a small number of naïve lymphocytes
Properties of adaptive immune response; specialization
Generates responses that are optimal for defense against different types of microbes
Properties of adaptive immune response; contraction and homeostasis
Allows immune system to recover from one response so that it can effectively respond to newly encountered antigens
Properties of adaptive immune response; nonreactivity to self
Prevents injury to the host during responses to foreign antigens
Properties of adaptive immune response; immunological tolerance
Ability of the immune system to coexist with self-antigens. Ensures immune system avoids destroying host tissue
