Week 6- The Immune System (pt 2) Flashcards
Inaccurate responses to the immune system
-Inadequacy to protect the host (immunodeficiency)
-Overexpression to a substance or hypersensitivity reactions
-Transfusion/transplantation reactions (alloimmunity)
-Reacting to the host’s own cells (autoimmunity)
True or false: The immune response is absent or depressed as a result of a primary or secondary disorder
True
Reflects a defect involving T cells, B cells, or lymphoid tissues; inherited defects in the genesis of the immune system
Primary immunodeficiency
Results from an underlying disease or factor that depresses or blocks the immune response; infection, aging, malnutrition, chemotherapy, autoimmune disorders, or immunosuppression
Secondary immunodeficiency
Genetic deficiencies of components of innate immunity
Complement proteins
Phagocytes
AIDS stands for…
Acquired Immunodeficiency Syndrome
True or false: AIDS is a primary immune deficiency
False
(secondary immune deficiency)
Three main avenues for the transmission of AIDS
-Contaminated blood
-Sexual activity (anal, vaginal, very rarely oral)
-Maternal to child (either through pregnancy, during delivery, or breastfeeding)
High-risk behaviors for AIDS
Unprotected anal, vaginal, and oral sex, including having six or more sexual partners in the past year, sexual activity with someone known to carry HIV, or IV drug use
True or false: HIV is transmitted by fomites, casual household or social contact
False
(transmitted via fluids)
HIV is a _______, also known as _________
Ribonucleic acid (RNA) virus
Retrovirus
This virus is surrounded by a lipid bilayer envelope containing the glycoprotein spikes
HIV
HIV predominantly infects human _____ cells and destroy them; also infect macrophages, B cells, dendritic cells, and microglial cells
T4 (helper) lymphocytes (CD4)
______ causes the global epidemic because it is more readily transmitted than another form of HIV
HIV 1
1-6 weeks; flu-like symptoms and lymphadenopathy (swelling of lymph nodes); antibody test remains negative
Acute infection of AIDS
1-20 years; CD4 count of 500 cells/mm3 or more; positive antibody test but still no reaction
Asymptomatic (AIDS)
Refers to the emergence of HIV antibodies in the bloodstream
Seroconversion
Between 200-500 cells/mm3 or more; persistent generalized adenopathy, nonspecific symptoms (such as diarrhea, weight loss, fatigue, night sweats, and fever), or neurologic symptoms resulting from HIV encephalopathy
Symptomatic (AIDS)
200 cells/mm3 or less
Advanced (AIDS)
True or false: The stages of infection vary from acute to asymptomatic to symptomatic and correlates with the level of the CD4 (lymphocyte) counts
True
Clinical manifestations of AIDS
-Neurologic manifestations/peripheral neuropathies
-Neuromusculoskeletal diseases
-Rheumatologic diseases
-Cardiopulmonary diseases
-Lipodystrophy syndrome
-AIDS-related lymphoma
True or false: HIV medications can cure the etiologic agent
False
(cannot cure)
True or false: HIV treatment can promote healthier lives and prolong the lives of people with HIV
True
True or false: Combinations of medicine are taken to prevent HIV from advancing to AIDS
True
True or false: The medicines used for HIV increase the risk of transmissibility to other people
False
(reduce)
Indicates that this illness is not a single disease but the result of a combination of factors
Chronic fatigue syndrome
Unexplained fatigue of greater than or equal to 6 months’ duration
Chronic fatigue
Etiologic factors and pathogenesis of Chronic fatigue and Immune dysfunction syndrome
Viral infections, immune dysfunction, neuroendocrine responses, dysfunction of the CNS, muscle structure, exercise capacity, sleep patterns, genetic constitution, personality, and (neuro)psychologic processes
Immune system
Endogenous normal flora
Gastrointestinal system
Genitourinary system
Respiratory system
Mucous membrane function
Skin breakdown
Altered defense mechanism
Exogenous and bacteria, fungi, viruses
Opportunistic agents: tuberculosis, pneumocystis, carinii pneumonia, cytomegalovirus, candida albicans
Infectious agents
The client
Invasive devices: tubing, catheters, needles
Reusable equipment
Reservoirs
Direct: hands, broken skin
Indirect: tubes, needles, dressings, catheters, equipment
Droplet: cough, sneeze
Vehicle: blood
Modes of transmission
Hand washing
Standard precautions
Clear/sterile techniques
Masks for respiratory diseases
Sterilize/disinfect equipment
Maintain skin integrity
Infection control strategies
4 types of hypersensitivity disorders
Type I- Ige-mediated/immediate type
Type II- tissue specific
Type III- immune complex mediated
Type IV- cell mediated
These compete with histamine for histamine receptors on cell membranes
Antihistamines
Two of the most common applications of antihistamines are…
-Treatment of respiratory symptoms caused by viral infections (ex: common cold)
-Respiratory allergic response to seasonal allergies and other allergens
Antihistamines are drugs that specifically block the ____ subtype of histamine receptors
H1
True or false: Newer “second-generation” antihistamines readily cross the blood-brain barrier and enter the brain, causing CNS-related side effects such as sedation and psychomotor slowing
False
(“First generation”)
Newer antihistamines, or second generation antihistamines, seem to be more ______ for the ____ receptor subtype and produce fewer side effects related to other histamine receptors and receptors for other neurotransmitters
Selective
H1
Which type?
-IgE-mediated reaction
-Immediate rate of development
-IgE involved
-Mast cells involved
-No complement participation
-Seasonal allergic rhinitis
Type I
Which type?
-Tissue-specific reaction
-Immediate rate of development
-IgG/IgM involved
-Macrophages in tissues involved
-Frequent complement participation
-Autoimmune thrombocytopenic purpura, Graves disease, autoimmune hemolytic anemia
Type II
Which type?
-Immune complex mediated reaction
-Immediate rate of development
-IgG/IgM involved
-Neutrophils involved
-No complement participation
-Systemic lupus erythematosus
Type III
Which type?
-Cell mediated reaction
-Delayed rate of development
-No antibody involved
-Lymphocytes and macrophages involved
-No complement participation
-Contact sensitivity to poison ivy and metals (jewelry)
Type IV
Type for these clinical manifestations:
-Varies according to allergies present
-Classic symptoms: wheezing, hypotension, swelling, urticaria,
rhinorrhea
-Anaphylaxis
Type I
Formed from a CD4+ Th2 (T helper 2) cell-dependent mechanism that binds with receptors on mast cells and basophils
IgE-mediated antibody (on B cells)
True or false: To activate the mast cell, the antigen crosslinks to more than one IgE antibody molecule
True
Mast cells release ________ that induces constriction of vascular and nonvascular smooth muscles, causing ___________ and increasing venule permeability (bronchoconstriction; wheal and flare in the skin)
Histamine
Vasodilation
IgG and IgM antibodies are involved in this hypersensitivity
Type II
The symptoms and reactions in type II hypersensitivity depend on what _______ expresses the particular antigen
Organ/tissue
Examples of antibody-mediated diseases
-Myasthenia gravis
-Graves disease (hyperthyroidism)
-Insulin-resistant diabetes
2 mechanisms of type II hypersensitivity (only need to know #1 and #2 out of the 5)
-ABO incompatibility transfusion reactions; receive wrong type of blood during blood transfusion
-Antibody may cause destruction of the cell via phagocytosis by macrophage
Involves interaction of antibody and complement, which may attract the polymorphonuclear cells or neutrophils
Type III hypersensitivity
Antibodies involved in type III hypersensitivity
IgG, IgM, and occasionally IgA
Most common tissues affected for type III hypersensitivity
Kidneys
Joints
Skin
Blood vessels
Example of immune-complex mediated diseases
Systemic lupus erythematosus
The presence of T lymphocyte–mediated reactions (no antibodies are involved)
Type IV hypersensitivity
True or false: Type IV hypersensitivity has an immediate type hypersensitivity reaction
False
(delayed)
True or false: There is a graft rejection or allergic reaction after receiving transplantation for type IV hypersensitivity
True
T-Cell mediated diseases
Rheumatoid arthritis
Multiple sclerosis
Type I diabetes mellitus
Hashimoto thyroiditis
Immune mechanisms directed against self-antigens
Autoimmune diseases
True or false: Autoimmune diseases occur when the body fails to distinguish self from non-self, causing the immune system to direct immune responses against normal (self) tissue and become self-destructive
True
More than ____ autoimmune diseases have been identified
56
Example for localized tissue damage occurs, resulting from the presence of specific autoantibodies
Hashimoto disease
Example for the lesion tends to be localized in one organ, but the antibodies are not organ specific
Primary biliary cirrhosis
Example for non-organ specific diseases in which lesions and antibodies are widespread throughout the body and not limited to one target organ
SLE
Disease in which the immune mechanisms are directed against self-antigens
Autoimmune diseases
True or false: When one has an autoimmune disease, their body fails to distinguish self from non-self, causing the immune system to direct immune responses against normal (self) tissue and become self-destructive
True
True or false: Less than 56 autoimmune diseases have been identified
False
(more)
True or false: The causes of autoimmune diseases are often determined
False
(not often determined)
Factors of autoimmune disease
-Genetic
-Hormonal
-Environmental influences
-Other factors (ex: viruses, stress, cross-reactive antibodies)
True or false: Although no single gene has been identified as responsible for autoimmune diseases, clusters of genes seem to increase susceptibility
True
The unresponsiveness of certain antigens induced by their exposure to lymphocytes
Immunologic tolerance
Lack of recognition and responsiveness to one’s own tissue antigens
Self-tolerance
Autoimmunity indicates loss of __________
Self-tolerance
Immature lymphocytes that recognize self-antigens during their maturation in central (generative) lymphoid organs
Central tolerance
Immature lymphocytes are killed by _________ in _________ tolerance
Apoptosis
Central
Mature lymphocytes that recognize self-antigens become either anergic (i.e., functionally inactive) or suppressed by regulatory T cells or undergo apoptosis
Peripheral tolerance
True or false: The mechanisms of autoimmunity can be associated with gene susceptibilities and epigenetic changes in tissue
True
True or false: Gene-mapping studies have demonstrated that allergy and autoimmunity only involve the recognition of antigen by T cells
False
(that and immunoregulatory effects of cytokines, inhibitory receptors, and survival factors)
Linkage analysis of human genome has revealed candidate locations for susceptibility to…
MS, type I diabetes, SLE, Crohn disease
True or false: Bacteria, mycoplasmas, and viruses do not trigger autoimmunity
False
True or false: In the concept of molecular mimicry, viruses and microbes share cross-reacting epitopes with self-antigens where microbial antigens tend to attack self-tissues
True
Two forms of lupus erythematosus (lupus)
DLE
SLE
Lupus that affects only the skin (usually the face, neck, and scalp)
Discoid lupus erythematosus
Lupus that can affect any organ or system of the body
System lupus erythematosus
True or false: DLE is more severe than SLE
False
(SLE is more severe)
True or false: No two people with SLE will have identical symptoms
True
True or false: SLE is primarily a disease in young women
True
True or false: Evidence does not point to interrelated immunologic, environmental, hormonal, and genetic factors that affect SLE
False
(it does)
True or false: It is known SLE represents a single pathologic entity with variable expression and a group of related conditions remains unknown
False
(unknown)
A higher incidence of SLE exacerbation occurs among women taking even low-dose ____________.
Estrogen contraceptives
True or false: SLE may also be triggered or aggravated by treatment with certain drugs, which could modify both cellular responsiveness and immunogenicity of self-antigens
True
Three main mechanisms implicated in the development of lupus…
Autoantibodies
Vascular abnormalities
Inflammatory mediators
One significant feature of SLE is the ability to produce antibodies against many different tissue components such as…
-Red blood cells
-Neutrophils
-Platelets
-Lymphocytes
-Almost any organ/tissue in the body
Clinical manifestation of lupus
-Musculoskeletal
-Cutaneous and membranous lesions
-Cardiopulmonary system
-Central nervous system
-Renal system
-Other systems
True or false: Transplantation of almost any tissue is feasible, but the clinical use of transplantation to remedy disease is still limited for many organ systems because of the rejection reaction
True
In all cases of graft rejection, the cause is __________ of cell surface antigens
Incompatibility
True or false: A recipient’s immune system does not recognize that the surface HLA proteins of the donor’s tissue are different from the recipient’s
False
(it does)
True or false: HLA matching of donor and recipient can enhance the probability of graft acceptance
True
