49 terms

Immune system

factors involved in infections?
portal of entry, virulence of organism, aggresiveness, toxin production, dose of pathogens, predisposition to infection
nonspecific defenses
effective against any harmful agent
specific defenses
effective against a certain agent only (vaccines)
examples of nonspecific defenses
mechanical and chemical barriers, phagocytosis, natural killer cells, inflammation, fever , interferon
mechanical barriers
intact skin and mucous membranes
chemical barriers
body secretions
WBCs engulf and destroy wastes and foreign material (neutrophils, macrophages)
change into macrophages
natural killer cells
recognize body cells with an abnormal membrane, they are found in lymph nodes, spleen, bone marrow, and blood
body's effort to get rid of anything that irritates it
heat, achiness, redness, pain, swelling
mast cells
release histamine
allows for dilation of blood vessels
indicates body defenses are at work, stimulates phagocytes, increases metabolism, decreases ability of certain organisms to multiply
interferes with the multiplication of viruses, interferon can also be used as a med to stimulate the immune system
gets rid of stuff in your body, sneezing, coughing, vomiting, diarrhea, protect the body
power to overcome a specific disease agent, selective
inborn immunity
species and individual immunity, population
acquired immunity
develops during a person's lifetime from encounters with specific harmful agents
any foreign substance that enters the body and induces an immune response
naturally acquired immunity
through contact with a specific disease organism, there is active and passive
active immunity
comes from having had the disease
passive immunity
natural, placenta, breast milk
artificially acquired active immunity
vaccination(immunization) controlled exposure to a disease producing pathogen, causes a persons immune system to manufacture antibodies
risks for artificially acquired active immunity
side effects, preventive measures
artificially acquired passive immunity
acquired by administration of immune serum (antiserum), short lived immunity, used in emergencies, often derived from animals, may cause a sensitivity reaction
live vaccine
kept in freezer
attenuated vaccine
dilute or weakened
toxin or poison that has been treated with chemicals or heat to decrease it's toxic effect but it retains it's antigenic power (tetanus) it will provoke an antibody response
genetically engineered vaccine
process of producing recombinate DNA for purpose of altering and controling, it uses enzymes insulin
a molecule, a cell, or an organism that results from the recombination of genes
active immunity does not always last a lifetime, repeated inoculation help maintain high titre of antibodies in the blood, number and timing varies with vaccines
examples of vaccines
pertussis, diphtheria tetanus toxoid, Hib, PCV, prevnar,
examples of viral vaccines
inactivated polio, measles, Hep B, hep A, varicella, influenza, rabies, rotovirus
a special treatment that involves administering gradually increasing dose of an offending allergen to help the person develop an immunity (allergy shot) desensitization
allows the person to build up a tolerance to the allergens without developing symptoms
risks of immunotherapy
anaphylaxis, doctor must always be in the building, keep pt for 20-30 minutes after injection, measure both weal and erythema
cytotoxic killer T cells
CD8 cells, work against cancer cells and cells infected with viruses
stem cells
a certain amount travel to the thymus gland and mature to T cells
T cells
originate in stem cells in bone marrow, become sensitized to specific antigens, produce cell mediated immunity, attack an antigen directly, cell to cell combat
helper T cells
infected and destroyed by HIV, help to regulate B cells and help them produce antibodies , don't function as effectively in the elderly
memory T cells
sleep until activated such as measles, chicken pox, hep B
B cells
attack antigens indirectly by producting antibodies that destroy antigens, provide active immunity, (immunizations) and passive immunity(immunoglobulin)
the four R's
recognize, respond, remember, regulate
self from nonself, normall the body recognizes its own cells as nonantigenic, therfore an immune response generally is triggered only in response to antigens except in autoimmune disorders
to non self invaders, the immune system responds in part by producing antibodies that target specific antigens for destruction, new antibodies are produce in response to new antigens if not can result in immunodeficiency disorders
the invader, the ability to remember antigens that have invaded the body in the past is the immune systems memory, allows a quicker response
it's action, self regulation allows the immune system to monitor itself by turning on when an antigen invades and turning off when the invasion has been eradicated, regulation prevents the destruction of healthy or host tissue, unable to do this results in chronic inflammation and damage to the host tissue