Overview of body defenses: lecture 1 Flashcards
What is immunity
Host defense against pathogens and toxins
Tissue repair
Host defense against mistakes in cell replication leading to cancer.
What is pathogen
Disease producing organisms.
Viruses, bacteria, protozoa, helminths, fungi, prions
Virulence is
A measure of how effective a pathogen is at invading a host and causing disease.
Inflammatory response happens when
First response to infection
How we use immunology
Testing
Understanding diseases e.g. allergies
Vaccine protocols
Neonatal care
Geriatric care
Three major types of protection
Physical barriers
Innate Immunity
Adaptive Immunity
These pathways do not work independently, they are interlinked
Innate immunity means
Rapid response
Adaptive immunity means
Specialist responders
What can cells act as
Some cells simply act as barriers.
Some cells are sentinels.
Alert other cells to problems - inflammation.
Some specialize in dealing with problems outside of the host’s cells
Some specialize in removing problems inside of the host’s cells.
Properties if innate immunity
Rapid
Non-specific
Consistent
Examples of cells in innate immunity
Phagocytic cells, complement.
Especially important at sites where pathogens are likely to enter the body.
properties of adaptive immunity
Specific
Discrimination (self and non-self)
Can differentiation between the two and only attacks non-self
Timeline is variable
Memory
Examples of Fixed defenses are
Gastric acid
Skin
Nasal secretions
Coughing/sneezing
Urination
Defecation
Fixed defenses are
Chemical
Physical barriers
Traps
Elimination
Commensal bacteria
Properties of lysozyme
Antimicrobial
Digests cell walls
Defensins are
Antimicrobial proteins produced by epithelial cells and neutrophils.
Makes pores in cell walls of bacteria, fungi and viruses
Antimicrobial chemicals in the innate immunity
Lysozyme
Defensins
Hair and skin does what for immune system
Lubricated and protected by sebum and sweat
Fatty acids lower pH
Defensins
Commensal bacteria
Fatty acids
Tough and inert
Constantly shed
Nose does what for immune system
Hairs
Turbinate bones
Mucus
Sticky
Contains lysozyme (antimicrobial enzyme)
Alveolar macrophages
Commensal bacteria
Surfactant
Trachea stops microbes by
Cilia
Mucociliary escalator
GI tract stops microbes by
Stomach
Acidity
Kills many pathogens.
What medicine will interfere with GI immunity
Antibiotics
Antacids
Ulcer prevention medications
Small intestine does what to stop infection
Sudden pH change
Peristalsis
Epithelial barrier
Mucus
Bile - antimicrobial substances and enzymes
Gut flora.
Compete for nutrients and space
Produce antibacterial compounds?
Defensins
How do eyes defend the body
Is this physical or physiological? Both
Protects against trauma
Tears
Flushing
Lysozyme
How does the urogenital tract stop infection
Flushing of urinary tract
Vagina
Commensal bacteria
Produce lactic acid
Prevent infection
Mobile defenses in the body are
Phagocytes
Neutrophils
Macrophages/Monocytes
Killer (NK) Lymphocytes
Complement
Interferon
