objective 8: immune alterations Flashcards
is the bodys ability to resist harmful microorganisms from entering and causing illness/disease
immunity
protect the body internal environment against invading organisms
defence
maintain by removed damaged cells from the circulation
homeostasis
serves as a network for recognizing and guarding against the development and growth of abnormal cells
surveillance
the immune system responds appropriately to a foreign stimulus
immunocompetence
the quality of being insusceptible to or unaffected by a particular disease or condition
immunity
the study of the immune system
immunology
Hyperactive response against
environmental antigens (allergy)
Inability to protect the body, as in
immunodeficiency disorders (AIDS)
Failure to recognize the body as self, as
in autoimmune disorders (systemic
lupus erythematosus)
Attacks on beneficial foreign tissue
(organ transplant rejection or
transfusion reaction)
altered immune responses
what are the types of immunity?
innate
acquired
active
passive
- Present at birth and is the first line of defence against pathogens
- Nonspecific and responds quickly
- Provides physical, mechanical, and chemical barriers to invading pathogens, and protects
against external environment - Skin, mucous membranes, cilia, stomach acid, tears, saliva, sebaceous glands, and
secretions of the intestines and vagina are all included in innate immunity
innate immunity
Second line of defence
Provides a specific reaction to each invading antigen
* Produces antibodies in the cells after an infection or immunization
Composed of thymus, spleen, bone marrow, blood, and lymph
tissue
acquired immunity
results from invasion of microorganisms into the body and production of specific antibodies
active
person recieves antibodies rather than synthesizing them
natural
what are the cells involved in immune response?
Macrophages
Lymphocytes
Antigens
Cytokines
- Engulf and destroy antigens that pass through skin
and mucous membranes via phagocytosis - Initiates immune response via lymphocytes
macrophages
A substance recognized by the body as foreign, and
can trigger an immune reponse
antigen
produce antibodies and alert the T cells
B lymphocytes
Destroy compromised cells in the body and alert leukocytes
through secretion of lymphokines
T lymphocytes
Chemical factor released by T cells that attracts
macrophages to the site of infection/inflammation
lymphokine
large granular lymphocyes involved in destruction of virus infected cells and tumour cells
NKC
Found in skin, mucous membrane lining, stomach, nose, etc.
Purpose is to capture antigen at site of contact with external
environment and transport to T cells to be destroyed
dendritic cells
A member of the granulocytic series and is named or the characteristics staining pattern of its granules as
well as its multilobed nucleus
neutrophils
are the larges normal blood cells (14-20 um in diameter)
monocytes
Are mildly phagocytic have 2 functions: 1) they serve as the body’s primary defense against parasites 2)
help regulate vascular mediators released from mast cells
eosinophils
the least prevalent granulocyte in the blood. Similar to mast cells in content and is an important source of
the cytokine IL-4 which is a key regulator of the acquired immune response. Often associated with
allergies and asthma. Primary role unknownb
basophils
Cellular fragments formed from megakaryocytes. Circulate in blood stream until vascular injury occurs. Can be
activated by many products of both the innate and adaptive immune responses, including collagen, thrombin, and
antigen-antibody complexes.
platelets
Are low-molecular-weight proteins that primarily protect against viral infections and modulate the inflammatory
response
interferons
Central cell in inflammation . Are cellular bags of granules located in the loose connective tissues close to blood
vessels.
mast cells
A vasoactive amine that causes temporary, rapid constriction of the large vessel walls and dilation of the post-
capillary venules, both of which result in increased blood flow into the microcirculation
histamine
Synthesized by the mast cells and are a product of arachidonic acid and cause increased vascular permeability.
prostaglandins
- Responds to antigens such as bacteria and foreign
tissue - Result of the development and continuing
presence of circulating antibodies in the plasma
humoral immunity
- Also called cell-mediated immunity results when T cells are activated by an
antigen. - Whole cells become sensitized in a process similar to that which stimulates
the B cells to form antibodies. Once these T cells have been sensitized, they
are released into the blood and body tissues, where they remain indefinitely
cellular immunity
what are the 4 Rs of immune response?
recognize
regulate
respond
remember
Normally the body recognizes its
own cells as non-antigenic;
therefore an immune response
generally is triggered only in
response to agents that the body
identifies as foreign
recognize self from non-self
disrupt the
ability to differentiate self from
non-self, and the immune system
attacks the body’s own cells as if
there were foreign antigens.
autoimmune disorders
the
immune system responds in part by
producing antibodies that target specific
antigens for destruction. New antibodies
are produced in response to new
antigens. Deficits in the ability to respond
can result in immunodeficiency disorders
such as HIV/AIDS
respond to non-self invaders
The
ability to remember antigens that
invaded the body in the past allows
a quicker response if subsequent
invasion by the same antigen
occurs.
remember the invader
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 the
healthy or host tissue The inability
to regulate could result in a chronic
inflammation and damage to the
host tissue This Photo by Unknown Author is licensed under CC BY
regulate its action
A controlled exposure to a disease-
producing pathogen that triggers antibody
production and prevents disease
immunization
Long term management option to treat allergies
Involves administering increasingly large doses of the offending
allergens to gradually develop immunity
Weekly injections of a very diluted antigen increasing in strength
over 1-3 years
immunotherapy
is the state in which the body’s immune system
can identify and inactivate or destroy foreign substances
immuno-competence
- An abnormal condition characterized by
excessive immune response to a particular
stimulus - Harmless substances such as pollens, foods,
and chemicals are recognized as foreign - Caused by a genetic defect that allows
increased production of immunoglobulin
hypersensitivity reactions
Most severe type of allergic reaction. IgE
Mediated
Immediate symptom onset upon second
exposure to allergen
System overreacts to venoms, medications,
insect bites, foods, etc.
anaphylaxis
IgG/IgM antibodies directly bind to
antigen on cell surface and cause cell
destruction via cytolysis or phagocytosis
Tissue damage occurs rapidly
ytotoxic and cytolytic reactions
Tissue damage caused by antigen-antibody complexes
Antigens combine with immunoglobulins and are too small to be effectively
removed by phagocytes
Complexes deposit in tissue and cause activation of inflammatory system
May be local/systemic and immediate/delayed
immune complex reactions
- Cell mediated immune response
- Tissue damage occurs due to T
lymphocytes release of cytokines
and attraction of macrophages - Takes 24-48 hours to occur
delayed hypersensitivity
An abnormal condition of the immune system in which cellular or humoral
immunity is inadequate and resistance to infection is decreased
May cause recurrent infections, chronic infections, severe infections, and/or
incomplete clearing of infections
Can be induced (chemotherapy)
May be Primary or Secondary
immunodeficiency
Disorders in which natural cells are attacked or destroyed by killer T cells and
autoantibodies
Diseases are considered autoimmune when they show steady, progressive tissue
damage without an identifiable cause
The immune system no longer recognizes the body’s normal cells as self but non-
self or foreign
The antigens on these normal cells are recognized as foreign material & an immune
response to destroy them is initiated
autoimmune disorders
what are the routes of transmission for HIV?
sexual
parenteral
perinatal
