Immune system Flashcards
What are the 3 components of the immune system?
- anatomic defenses
- innate {natural} immunity
- acquired {adaptive immunity
Anatomic defenses include
- skin
- mucous membranes
- mucous blanket
- ciliated cells
innate {natrual} immunity what is needed
nothing/doesn’t require a previous infection
Acquired {adaptive} immunity needs what to respond
vaccination or history with an antigen
When is the Innate {natural} immunity present
from birth and remains throughout life
The innate {natural} immunity is composed of what
- PMNs
- phagocytic cells
- complements
When is Acquired {adaptive} immunity present
builds with age and begins with exposure
The acquired {adaptive} immunity is composed of what
- T cells
- B lymphocytes
- natural killer cells
B cells are from what area in the body
the bone
B cells are what type of immunoglobulins
antigen-specific
What are the different types of B cell immunoglobulins
- IgM
- IgG
- IgA
- IgD
- IgE
T cells are from which part of the body
thymus
What is the role of IgM
- body’s first response to infection
When should you look for IgM
when testing a patient for infection
Where is IgG present
all internal body fluids
What is IgA and where is it present
it is protective in external secretions
found in GI, respiratory, and genital tracts, and are present in the circulation
Where is IgE present
in internal and external body fluids
IgE and eosinophils respond to what
allergy and parasitic infections
What is the significance of IgD
unclear
deficiencies in IgD may exist when
when total Ig levels are normal and happens specifically with IgG and IgA
What are the steps in primary immune response
- antigen is carried to lymph node
- Virgin B cells respond
- if affinity for antigen is sufficient, B cell develops into antibody-producing plasma cells
- CD40 glycoprotein acts with CD154 on T cells to proliferate B cell and synthesize IgM
- B cells become memory cells that can mount specific IgG, IgA, or IgE response
Is primary or secondary immune response more rapid
secondary response is more rapid than primary
what is the role for natural killer cells
secondary immune response
in noenates what type of cells are present in high numbers
T cells
How does neonate immune differ from adult
ratio of CD4 to CD8 cells differ
normal newborns have the capacity to develop what
antigen-specific T cell response
Why do neonates have a high susceptibility to infections with gram-negative organisms
- lack of IgM because IgM cannot cross placenta
2. impaired phagocytosis
What is a risk in neonates because of their normal high T cell count
presence of severe immunodeficiency without being recognized.
IgM in neonates to adult
increase over time and reach adult levels by age 1
Is IgA exchanged through breastmilk
at least some is received via breast milk
When does IgA production begin and when does it reach adult levels
begins around 2 weeks of life, and reaches adult levels by age 6-7
IgG levels at birth
initially high from maternal sources but taper by 6-8 months
IgG production begins when
after maternal sources leave around age 6-8 months and reach adult levels by age 7-8
IgE production
mimic IgA;
begins around 2 weeks and reaches adult levels by age 6-7 years
When are the lowest total IgG levels
age 3-4 months
Neonate antibody production
can make some specific antibodies at birth
When can newborns mount an immune response to polysaccharide antigens
after 2 years of age;
**polysaccharide vaccines are ineffective for newborn and therefore require a conjugated vaccine
lymph tissue continues to grow until when
school age
thymus in adolescence
size starts to wane in size
Thymus by middle age
is at 15% of its initial size
T cell function over time
declines after middle age
Middle age and immunity
- infections develop more easily
2. vaccines become less effective
Older people are more prone to what
more prone to autoimmune disease
in older people, risk for infection is frequently complicated by
comorbidities and medications
What is the NPs role in managing infection
- refer to an infectious disease specialist
What is considered primary prevention
- preventing infection in the first place
- identify and respond to infection quickly
- comanage chronic infection with a specialist
What are the steps in the secondary immune response
- memory B cell encounters antigen
- Plasma cells form
- IgG, IgA, and IgE are made
- natural killer cells also play a role
Where is IgM confined and why
they are large so they are confined to intravascular compartment
The thymus with aging
it begins to shrink after adolescents;
by middle age it is 15% of original size
T cell with aging
T cell function declines with age while T-cell numbers are not affected
