Lecture 29: Neonatal Immunology and Immunosenescence Flashcards
Neonates are immunologically naive, they can mount an immune response but lack exposure to antigen therefore all responses are ___ and ____
Primary and slow
What is immunosenscence
Occurs in aging animals and refers to the gradual deterioration of function and the immune system
What is the first immune organ to develop in fetus
Thymus
What is last immune organ to develop in fetus
Peyers patch
What is average gestation for calf
280 days
When can lymphocytes be found in calves
45 days
When can B cells be found in calves
59 days
Fetal cows can respond to viruses experimentally between 73-120 days already- what does this tell us
They can already distinguish between self and non-self
What is average gestation for foal
340 days
When do lymphocytes appear in thymus of foal
60-80 days
When can lymphocytes be found in blood of foal
120 days
When can plasma cells be found in foal
240 days
Report shows GVHD in immunodeficient host what kind of response does this demonstrate
Cell-mediated
When do horses begin IgE production
9-11 months
Average gestation for lamb
145 days
When do lymphocytes appear in blood of lambs
32 days
When can fetal lambs begin responding to viruses
50 days
How does the proportion of a/B and y/d T cells change in lamb over time
1 month prepartum- 18% of T cells are y/d
1 month postpartum 60% of T cells are y/d
What is average gestation for piglets
115 days
When does thymus develop in piglets
40 days
When can lymphocytes be found in piglets
38 days
When can B cells be found in piglets
50 days
Piglets have no __ cell activity until the piglet is several weeks old
NK
When can fetal pigs reject allografts
58 days
When does a VDJ rearrangement occur in piglets
30 days
What is average gestation in dog
60 days
When does thymus develop in dogs
23-33 days
When can fetal puppies reject allografts
45 days
Intrauterine injection of antigen before __ days can induce tolerance
42 days
What is average gestation in cats
65 days
What is average inoculation in chicks
21 days
When can lymphocytes be found in bursa of chicks
24 days
When are antibodies produced by chicks
16-18 days
When can eggs be vaccinated
18 days
What diseases can eggs be vaccinated against at 18 days
New castle, Mareks and coccidiosis
What is average gestation for opossum
15 days
T/F: opossum (marsupials) have no immune tissue or organs at birth
True
Blue tongue virus vaccine when given to pregnant female at ___ days causes severe neurological lesions in fetus
50 days
When should bluetongue virus vaccine be given to pregnant female to avoid neurological lesions in fetus
100 days
What are the two forms of BVD
Cytopathic and non-cytopathic
Which form of BVD causes persistent infection
Non-cytopathic
What does it mean to be a persistently infected calf
Infected with disease early on in utero that calf recognizes antigen as self and won’t mount an immune response therefore appears healthy
Infection of cow up to 50 days with BVD results in what
Abortion
Infection of cow with BVD between 50-120 results in what
Tolerance, persistently infected calves, immunosupression
T/F: persistently infected calves with BVD are usually asymptomatic but still can shed the virus
True
Infection with BVD between 100-150 days results in which form and what side effects
Cytopathic form, results in birth defects
Infection with BVD between ___ days has no effect
150-180
Persistently infected cows with BVD can develop what disease
Mucosal disease
What Th response do neonates mount
Th2
Neonates have increased susceptibility to what type of pathogen
Intracellular pathogen (Rhodococcus equip
What is passive immunity
Immunization through transfer of specific antibody from immunized individual to non-immunized individual
What kind of placenta do cats and dogs have
Endotheliochorial
Cats and dogs inherit 5-10% of what Ig in utero
IgG
What type of placenta do ruminants have
Syndesmochorial
What type of placenta do pigs and horses have
Epithelialchorial
What antibodies are transferred to pigs and horses through placenta
None! All Ig’s are transferred through colostrum
Chicks receive passive transfer from hens serum while still in ___
Ovary
No prepartum ___ transferred to goals
IgG
Where must goals get IgG
Colostrum (secreted for 24hrs)
IgG is ___% of antibody content in domestic species
65-90%
What is predominant Ig in colostrum and milk for pigs and horses
Colostrum- IgG
Milk- IgA
What is predominant Ig in colostrum for ruminants
IgG
How are antibodies absorbed from colostrum in intestines
Bind FcRN receptors, endocytosed and then delivered to blood
Which Ig remains in intestinal epithelium for pigs and horses
IgA
What antibodies remain in intestinal epithelium for ruminants
None- all absorbed
What can cause failure of passive transfer
- Poor quality colostrum
- Failure of neonate to ingest colostrum
- Failure of neonate to absorb colostrum
What are some treatment options for failure of passive transfer
Banked colostrum or plasma transfusion
Which neonates often can’t absorb colostrum
Premature
How to measure colostrum qualtiy
Colostrometer
Ig’s from colostrum provide neonate with ___ immunity
Systemic (IgG)
Ig’s from milk provide neonate with ___ immunity
intestinal (IgA)
When should puppies start getting vaccinated
6-9 weeks
When should foals start getting vaccinated
4-5 months
What are aging changes to neutrophils and macrophages
Decrease ability for respiratory burst, less able to destroy phagocytized bacteria
What cells reduce in number, reduced TLR expression, decrease production of IL-6, TNF-a and have reduced response to INF-y with age
Macrophages
Which cells have less effect APC and decreased ability to stimulate B cells with age
Dendritic cells
Which cells have decreased ability to destroy tumor cells with age
NK cells
Lymphocytes show reduction in what type of T cell with age
Cd8+
antibodies decline in ___
Affinity
