Development of the Immune System Flashcards
HSC progenitors are formed in the ______ and _________. They eventually migrate the the ___________ and _______.
Yolk Sac and Foetal Liver
Bone Marrow
Thymus
HSC colonise the foetal thymus by week __
8
Foetal Development of Immunity is done by about _______________________
Halfway through gestation
When do monocytes start to appear in circulation?
When HSCs start to seed to liver
What happens to Monocytes as Gestational Age Increase?
They increase in number and gain improved expression of phagocytic Fc receptors which results in enhanced phagocytic and antigen presentation capacity
Foetal monocytes are _____ functional than adult monocytes and so the foetus is _____ susceptible to infection
Less
More
What happens to neutrophil levels after 31 weeks of gestation?
Before 31 weeks levels are scarce, they then increase exponentially in numbers possibly to help protect the child from harmful pathogens as it is exposed to the world
A reserve neutrophil storage pool exists in the ______________, ________ and _______.
Bone Marrow
Liver
Spleen
Neonatal neutrophil function is __________
Impaired
The ability of neutrophils to migrate is ________ in pre-term infants. This means they are _____ susceptible to infection.
Delayed
More
The levels of dendritic cells _________ with age and _______ by 5 years old.
Increase
Double
Children with delayed dendritic cell maturation have higher frequency of ____________________________.
Lower respiratory tract infections
NK levels vary _________ with gestational. While NK cell levels are ______, they have _________ cytotoxicity and _________ functionality.
Proportionally
High
Decreased
Different
Complement factors are produced in the __________. Compared with adults they have a lower ___________ and __________ complement activation
Foetal liver
Qualitative
Quantitative
T-cell levels are _____ at birth and ________ during the first year. Their functionality is _____ due to decreased production of ____. T-cell levels ________ until they reach normal levels at __________.
High at birth Increase Low IL-2 (Interleukin 2) Decrease School age
B-cell levels are _____ at birth and ________ initially and then they _______ until they become adult levels over the first years.
High
Increase
Decrease
____ is the most common antibody at birthday because _____________________.
IgM
Class switching is a rare event
Infants get their ___ levels from their mother through the ________ and _________. They can protect the baby for up to ________.
IgG
Placenta and breast milk
6 months
Transplacental transport of ___ occurs via neonatal FC receptors on placental ______________________.
IgG
Syncytiotrophoblasts
The proliferative capacity of HSCs ________ with age. We get a shift towards making ____________. This is associated with changes to the ______.
Decreases
Myeloid Progenitors
DNA
What changes occur to the skin as we age?
- Decreased skin cell replacement
- Decreased sweat production
- Depletion of Langherhans cells and Melanocytes
- Dermal and subcutaneous atrophy
How do dendritic cells change with aging?
- Not many changes in healthy ageing, however;
- Langerhans cells levels decrease
- Reduced ability to respond to pathogens
The _______ in NK cell levels as we age is to counteract the ________ in functionality
Increase
Decrease
Neutrophils levels are __________ affected with increasing age. They have an ________ ability to phagocytose.
Not greatly
Decreased
The number of macrophages _________ in the elderly. Their ability to produced cytokines is _________.
Decrease
Decreased
Naive B-cell numbers ________ with age and their ability to respond to new antigens ________.
Decrease
Decreases
The absolute number of T-cells ________ with age this is due to _______________
Decreases
Thymic involution
