2. Immunity Flashcards
Ability of the body to protect itself from invasion of pathogens agents and provide a defense against their harmful effect
Can be classified as non specific or specific
Immunity
Natural/innate that is already present at birth
Functions in a standardized manner when subjected to challenge regardless of the nature of pathogen
Does not distinguish on pathogen from another
Non-specific immunity
(Innate immunity)
NOTE:
Components of non specific immunity:
Physical (Flushing mechanisms such as sweats etc)
Skin
Adaptive/Acquired that has the components of immune system that adapts
This leads to formation of antibodies and / or sensitized T cells
HALLMARK: Antibody production
Specific immunity
What are the properties of specific immunity?
Specificity and memory
ability to act on specific antigen
Specificity
Factors affecting protection by specific immunity
- Infectious dose (Depending the dosage of this microorganisms, it will activate the specific immunity)
- Route of administration
- Type of agent (Not all agent [Antigen] triggers immune response)
Lowest infectious dosage (Bacteria)
Shigella spp.
Type of specific immunity?
Active and Passive spcific immunity
Advantage: Long-term immunity
Disadvantage: Takes time to be established
Active specific immunity
Infection is occured due to exposure to immunogens creating antibodies
Natural active specific immunity
Vaccination is used for exposure to create antibodies
Artificial active specific immunity
Hallmark of active specific immunity?
End product: creates Antibodies
Advantage: Easily established
Disadvantage: Short term protection
Passive specific immunity
Breastfeeding gives antibodies
Natural passive specific immunity
Immunization is given to give antibodies
Artificial passive specific immunity
What is the hallmark of passive specific immunity?
Given Antibodies
What cell retains the memory in active specific immunity
Memory cells
LIne of immune defenses
- Non Specific immunity
- Specific immunity
First line of immune defense
Anatomical barriers and body functions
Genetic susceptibility and non susceptibility
Provision of unfavorable environment for pathogens
Normal flora
Flushing mechanism
Factors that influence the first line of defense
- Age
- Nutrition
- Comorbidities
Provides physical barrier and has active mechanisms for killing pathogens
Self sterilization by desiccation, desquamation, pH and fatty acid secretion
S. aureus can survive in fatty acid environmment
Skin and mucous membranes
NOTE: The acidity / Alkalinity of the stomach, intestinal tract and vagina inhibits microbial growth (Such as H. pylori)
L. acidophilus
Non-pathogenic microorganisms that prevents colonization of pathogenic microorganisms
Normal flora
Example of flushing mechanisms
Lacrimation
micturition
Cilia
Defacation
NOTE: Negative in Duffy antigens prevents malaria