are phagocytic cells
Which cells are required to process and present antigens from foreign material as the initial step in the immune response?
Humoral immunity is mediated by
B-lymphocyes (B cells)
A patient experienced an episode of influenza 6 months ago. A recent exposure to a mutated form of the same virus would result in
a primary immune response
Which type of immunity is provided by a vaccination?
When an allergen binds with IgE antibodies on mast cells, resulting in release of chemical mediators, this reaction is called:
type I hypersensitivity
The role of memory cells is to
recognize the antigen and stimulate the immune response
Which statement applies to contact dermatitis?
A type IV reaction occurs in specific areas
Which of the following causes anaphylaxis?
a severe, systemic allergic reaction
Why is anaphylaxis considered a critical situation?
bronchoconstriction and systemic vasodilation develop rapidly
Incompatible blood transfusions result in
hemolysis and erythrocytes
An autoimmune disease is
failure of the immune system to distinguish self from nonself
Systemic lupus erythematosus is caused by
immune complex deposits of antinuclear antibodies
Distinguishing clinical features of systemic lupus erythematosus include
inflammation in multiple organs
Which are target cells for HIV?
helper T-lymphocytes (CD4 lymphocytes)
A diagnosis of HIV positive means that
the virus and its antibodies are in the blood
HIV infection impairs
both humoral and cell-mediated immunity
HIV is transmitted by
blood, semen and vaginal secretions from an infected person
Serious infections frequently occurring in patients with AIDs include
Which statement does NOT apply to MHC proteins or molecules?
all members of a family have identical MHCs
CD-4 positive helper T-cells function by
facilitating all immune system activity
Host-versus-graft disease refers to
transplant rejection by the recipients immune system
Which of the following complications does NOT occur frequently in AIDS patients?
Which of the following characteristics apply to the agent HIV?
It tends to mutate frequently to form new strains
It is inactivated by heat and many disinfectants
In cases of HIV infection the "window period" refers to the time between
entry of the virus into the body and the appearance of antibodies in the blood
Which of the following is an effect of cytokines?
They activate and stimulate proliferation of B and T lymphocytes
What does seroconversion mean in relation to HIV and AIDS?
Antibodies for HIV have been indentified in the blood
Which of the following statements is true regarding a patient who is HIV positive?
Antibodies in the blood indicate presence of virus and possible transmission to others
The term tolerance refers to
the ability of the immune system to ignore "self" cells
Which of the following statements apply to the complement system?
It consists of proteins in the blood that must be activated
Which of the following statements regarding immunoglobins is TRUE?
They consist of a unique sequence of amino acids
Which of the following is NOT a cause of immunodeficiency?
Which statement is TRUE regarding infants born to HIV infected mothers?
Infants test positive for HIV due to presence of maternal antibodies
The most common cause of death in AIDS patients is
Pneumocytis carinii pneumonia