Chp 1 from pp Flashcards
Immune System
Network of cells, tissues, organs, proteins, biological structures and processes that work together to protect against disease (pp); the tissues, cells, and molecules involved in the defense of the body against infectious agents (txtbk)
Vaccination/immunization
a procedure whereby severe disease is prevented by prior exposure to infectious agent in a form that cannot cause disease; Vaccination programs rely on immunological memory to provide long lasting protection (pp). The deliberate provocation of an adaptive immune response by introducing antigens into the body; The deliberate induction of protective immunity to a pathogen by the administration of killed or non-pathogenic forms of the pathogen, or its antigens, to induce an immune response (txtbk). The first vaccines were by Edward Jenner for smallpox using cowpox through the process of variolation
pathogen
Micro-organisms (infectious organisms) that cause disease. They can be known infectious agents or ones that normally colonize the body. There are four classes: bacteria, viruses, fungi, and parasites (worms and protozoa) (pp). An organism, most commonly a microorganism, that can cause disease (txtbk)
opportunistic pathogen
Microorganisms that normally do not cause disease; They cause illness (disease) if body’s defenses are weakened (immunocompromised person) or if they get into ”wrong” place (immunologically privileged sites) (pp). a microorganism that causes disease in individuals whose immune systems are in some way compromised (txtbk)
commensal species
Most commensal species are benign or beneficial. We have co-evolved to take advantage of beneficial relationships; They aid in human nutrition by helping with digestion and making vitamins; They also block colonization by pathogenic organisms (pp). a microorganism that habitually lives on or in the human body; one that normall causes no dises or harm and can be beneficial (txtbk). The sum of all of our commensal microorganisms is the microbiota
emerging pathogen
Emerging pathogens infect organisms outside their normal host range which often leads to a high mortality rate, ex: Ebola virus (pp)
barrier defenses
includes physical and chemical barriers. Physical includes the epithelium (skin and mucosal surfaces) and all epithelial surfaces secrete antimicrobial substances (peptides, enzymes etc.,). Tears and saliva contain the enzyme lysozyme which dissolves the cell wall of bacteria (pp)
mucosal surfaces
Mucosal surfaces (mucosae) – epithelial lining (continuous with skin) of respiratory, gastrointestinal and urogenital tracts that are continually bathed in mucus that they secrete. Mucus is a thick substance made up of glycoproteins, proteoglycans, and enzymes (pp). mucus-secreting epithelium such as the lining the respiratory, intestinal, and urogenital tracts. The mammary glands and the conjunctiva of the eye are also considered in this category. Mucosal epithelium communicates with the external environment and is the route of entry of most pathogens (txtbk)
innate immunity
includes two phases: 1) Recognition of the pathogen – not pathogen specific, but relies on identification of components that are common to groups of pathogens (Pathogen associated molecular patterns or PAMPs) and mechanisms that mark pathogens non-specifically (complement) 2) Recruitment of effector cells that destroy the pathogen. It is much faster than the adaptive immune response. The immune response that is initiated immediately on infection and does not depend on lymphocytes. It depends on hose defenses such as complement, neutrophils, macrophages, and NK cells, which provide nonspecific defense against a wide range of pathogens. This response does not generate immunological memory (txtbk)
inflammation
Hallmarks: heat, redness, swelling, pain, and loss of function (calor, rubor, tumor, dolor, and function laesa). Major inflammatory cells are neutrophils (blood) and macrophages (tissue) (pp). General term for the local accumulation of fluid, plasma proteins, and white blood cells that is initiated by physical injury, infection, or a local immune response. The cells that invade tissues and help mediate inflammation are often called inflammatory cells, Those cytokines that promote inflammation are known as inflammatory cytokines (txtbk)
adaptive immunity
Unlike the innate immune which recognizes common features of pathogens, the adaptive immune response recognizes specific details of pathogens. The adaptive immune response also improves its ability to recognize pathogens during the response. This process fine tunes the adaptive immune response to a specific pathogen. Lymphocytes are the effector cells of the adaptive immune response. Pathogen specific lymphocytes are activated and expanded during the response. Some of these lymphocytes remain after the infection has been eliminated (pp). The state of resistance to infection that is produced by the response of antigen-specific B and T lymphocytes to antigen, including the development of immunological memory (txtbk)
immunological memory
Produced by some of the lymphocytes remain after the infection has been eliminated. Memory cells are rapidly activated if a pathogen is encountered a second time and their response is more forceful, such that the second infection is often stopped before symptoms are felt. (Vaccinations are dependent on imm. memory) (pp). The capacity of the immune system to make quicker and stronger adaptive immune response to successive encounters with an antigen. It is specific for a particular antigen and is long-lived (txtbk)
primary response
results from the initial infection of a specific pathogen (called the primary infection). Takes 1-2 weeks to respond. Compared to the secondary response it is slower with more lag, lower response (fewer antibodies), and have lower affinities (pp). The adaptive immune response that follows a person’s first exposure to an antigen (txtbk)
secondary response
Any infection from a pathogen from which a person has already had a primary response. Takes days to respond. Compared to the primary response, it is faster, with a higher level of response (more antibodies) and a higher affinity (pp). The adaptive immune response provoked by a second exposure to an antigen. It differs from the primary response by starting sooner and building more quickly, and is due to the presence of long-lived memory B cells and T cells specific for the antigen (txtbk)
hematopoiesis
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