Chapter 36 Active, Passive and Adaptive Immunity Flashcards
What is active immunotherapy?
systemic and non-specific activation of immune responses
What is active and specific immunotherapy?
T- or B-cell activation of specific antigen recognition pathways
What is adaptive immunotherapy?
cells with antigen-specific or non-specific effector responses are expanded in vitro and given to the host
What is passive immunotherapy?
preformed specific or non-specific antibodies are given to the host
How were British soldiers immunized against tetanus in WWI?
Through passive immunity from horse serum after horses were immunized with tetanus
What is the major fallback or passive immunity from horse serum?
hypersensitivity reaction upon second exposure to the horse antibodies
Which populations would benefit from passive immunity?
Those who cannot build an immune response from vaccines, such as bone marrow and solid organ transplant recipients and pregnant women
What indications were discussed to receive pooled human normal plasma, and how many donors would this required?
-X-linked agammaglobulinaemia / hypogamma-globulinaemia (individuals can get pool human Ig Q3 weeks)
-Common variable deficiency
-Wiskott–Aldrich syndrome
-Ataxia telangiectasia
-IgG subclass deficiency with impaired antibody response
-Chronic lymphocytic leukaemia
-Post-bone marrow transplantation for CMV pneumonitis in conjunction with an antiviral agent
(1000–6000 donors)
How are monoclonal antibodies traditionally produced?
Mouse spleen cells from immunized mice are fused to myeloma cells using polyethylene glycol. Culture in medium containing hypoxanthine aminopterin thymidine (HAT) allows only fused hybridoma cells to survive and these cells can then be cloned by limiting dilution. Those hybridomas making the antibody you want can then be selected.
Describe the structure of a chimeric antibody
The Fc region is genetically engineered to be human and the Fab region is mouse Ab
Describe the structure of a humanized antibody
only framework regions and complementarity-determining regions are from mice, rest is human
What mechanisms will antibody fragments lacking Fc regions be effective against, and which ones will it not be effective against?
effective at blocking cognate enzyme-substrate, hormone or toxin-receptor and microbial addressin-epithelial cell receptor interaction
Will not provide protection where complement fixation, phagocytic uptake or extracellular killing is required to eliminate a pathogen.
What microbial materials have been used as non-specific immunostimulators?
1891-Coley’s toxin (Filtered cultures of Streptococci and Serratia marcescens used against tumors)
•BCG (bacillus Calmette–Guérin)
•Streptococcal-derived OK432 (possible immunomodulator in cancer immunotherapy)
What endogenous material have been used as non-specific modulators?
-Thymus factors and hormones
•Cytokines, such as interferons used to treat chronic viral hepatitis B and C infections
What endogenous molecule was used to treat metastatic cancer in the 1970s, how did it exert its effects, and what were the side effects?
1970’s: large doses of IL-2 were used to treat metastatic cancers by enhancing T-cell production
However, the unpleasant side effects of high-dose therapy with interleukins or IFNs restrict their use and include:
• fever
• malaise leading to fatigue
• muscle pain
• toxicity to the kidney, liver, bone marrow and heart.
