Humoral Immune Response II Flashcards
describe the 3 main mechanisms of antibodies?
describe the process of neutralization
neutralization is the main function of which immunoglobulin?
IgA
name the 2 most important Fc receptors
IgG contains the most Fc receptors, therefore, is the best at opsonization
describe the process of opsonization (Fab/Fc region)
describe antibody-dependent cellular cytotoxicity (ADCC)
describe eosinophil-mediated killing
describe complement mediated opsonization and cytolysis
describe the functional activity and distribution of the different immunoglobulins
name the major immunoglobulin involved in opsonization
IgG1
name the major immunoglobulin involved in neutralization
IgG1,2,3,4 but mainly IgA
name the major immunoglobulin involved in sensitization of mast cells
IgE (FcƐR1)
name the major immunoglobulin involved in activation of the complement system
IgM
name the major immunoglobulin involved in transport across epithelium
IgA
name the major immunoglobulin involved in transport across placenta
IgG1
summarize the effector function of the antibodies
describe the process of mucosal immunity
- IgA is produced in mucosal lymphoid tissues
- transported across epithelia
- neutralizes microbes in lumen of mucosal organs
describe the process of neonatal immunity
- maternal antibodies are actively transported across the placenta to the fetus
- also across the gut epithelium of neonates
- incomplete immune systems
- passive immunity from the mother
- acquire IgG by 2 routes that rely on neonatal Fc receptor (FcRn):
- placenta while in uterus
- gut after ingestion of mother’s colostrum
describe the mechanism of immune evasion by pathogens
describe whole vaccines: killed or inactivated
- in killed or inactivated vaccines the microbial agent is treated with heat, chemicals or radiation
- usually don’t require refrigeration, easy to store and transport
- stimulate a weaker immune response: humoral only
- more likely to require multiple doses and boosters
- killed whole bacterial vacines:
- cholera, plague
- inactivated whole viral vaccines:
- polio (Salk), rabies, influenza hepatitis A
describe whole vaccines: live attenuated
- attenuation: any porcess that substantially weakens or negates the virulence of a microbial agent (easier for viruses than bacteria)
- live attentuated vaccines:
- stimulate a strong immune response: humoral + CMI
- require fewer doses and booster shots
- require refrigeration, more difficult to transport
- possibility of reversion (back mutation to wild type)
describe acellular and subunit vaccines
- selected antigens from the microbe rather than the whole organism are used (immunodominant protein)
- toxoid vaccines (acellular): formalin treated bacterial toxin
- conjugate vaccines (acellular): encapsulated bacteria (incapable of activating CMI)
- subunit vaccines: viral components
describe recombinant vacciens
- recombinant vector vaccines
- selected genes for microbial antigens are cloned into a vector
- the cloning host will produce the antigen for use in a vaccine
- DNA vaccines
- DNA plasmids encoding antigenic proteins injected into patient
- expression of foreign proteins in host cells
- strong humoral and CM response
summarize the production, booster requirement, relative stability, type of immunity induced and reversion tendency for attenuated, inactivated and DNA vaccines
___ is the only isotype useful in diagnosing infections in neonates
IgM is the only isotype useful in diagnosing infections in neonates
