When the parasites leave these cells and vulnerable to the host’s defenses move between other cells, they are: Some parasites disguise themselves by acquiring host antigens what? The process of evasion some parasites antigenic variation employ is called: The host builds what antibody to IgM reducing the infection? How does the parasite respond to making by changing its antigen the current antibody ineffective? How long does the process of antigen Long periods of time switching continue for? What is another mechanism of Antigen shed escape for parasites? Why is the immune response unable to The antigen is not attached to the parasite harm the offending organism of the parasite? What may result from molecular Parasitic antigens that are similar to antigens mimicry? normally found on host tissue What may molecular mimicry lead to? Autoimmune problems Why is the host rarely able to totally Parasitic infections can be chronic eliminate the source of infection? Why is the host’s immune system forced Due to the chronic infection to remain active? What are the results from the host’s Immunosuppression, disruption of normal B-cell and immune system remaining active? T-cell functions, and hypersensitivity reactions Working in concert, which several cell B and T lymphocytes, natural killer cells, types actively participate in the macrophages, other antigen-presenting cells, recognition and elimination of parasites granulocytes, and mast cells from the host? Which soluble substances also Immunoglobulins, complement, and cytokines participate in the host’s defenses? As part of the innate immune defense, Phagocytes to destroy both intracellular and what do neutrophils act as? extracellular parasites What does hydrogen peroxide kill? Extracellular organisms What do neutrophilic granules destroy? Ingested organisms The gamma interferon produced by Replication of the intracellular parasites natural killer cells inhibits what in the parasites? How does complement activation Through the production of chemotactic components, provide protection? opsonization for enhanced phagocytosis, and lysis of extracellular parasites What is cellular immunity responsible The production of cytokines and chemokines, which for? enhance the cytotoxic function of effector cells, increase the numbers of immune cells, and attract immune cells to the site of infection
When the parasites leave these cells and move between other cells, they are: vulnerable to the host’s defenses Some parasites disguise themselves by what? acquiring host antigens The process of evasion some parasites employ is called: antigenic variation The host builds what antibody to reducing the infection? IgM How does the parasite respond to making the current antibody ineffective? by changing its antigen How long does the process of antigen switching continue for? Long periods of time What is another mechanism of escape for parasites? Antigen shed Why is the immune response unable to harm the offending organism of the parasite? The antigen is not attached to the parasite What may result from molecular mimicry? Parasitic antigens that are similar to antigens normally found on host tissue What may molecular mimicry lead to? Autoimmune problems Why is the host rarely able to totally eliminate the source of infection? Parasitic infections can be chronic Why is the host’s immune system forced to remain active? Due to the chronic infection What are the results from the host’s immune system remaining active? Immunosuppression, disruption of normal B-cell and T-cell functions, and hypersensitivity reactions Working in concert, which several cell types actively participate in the recognition and elimination of parasites from the host? B and T lymphocytes, natural killer cells, macrophages, other antigen-presenting cells, granulocytes, and mast cells Which soluble substances also participate in the host’s defenses? Immunoglobulins, complement, and cytokines As part of the innate immune defense, what do neutrophils act as? Phagocytes to destroy both intracellular and extracellular parasites What does hydrogen peroxide kill? Extracellular organisms What do neutrophilic granules destroy? Ingested organisms The gamma interferon produced by natural killer cells inhibits what in the parasites? Replication of the intracellular parasites How does complement activation provide protection? Through the production of chemotactic components, opsonization for enhanced phagocytosis, and lysis of extracellular parasites What is cellular immunity responsible for? The production of cytokines and chemokines, which enhance the cytotoxic function of effector cells, increase the numbers of immune cells, and attract immune cells to the site of infection