Immunology Flashcards
Natural killer cells belong to which cell type?
Lymphocytes (large granular lymphocytes)
NK cells bridge the innate and adaptive arms of the immune system.
High levels of which immunoglobulin are found in breast milk?
IgA
Capturing, processing and presenting the antigen to T cells are the only functions of which type of cell?
Dendritic cells
How can the mechanism of action of the immunosupressive agent azathioprine best be described?
Inhibition of nucleic acid synthesis in all mitotic cells
Tacrolimus blocks T cell activation.
Haemolytic disease of the newborn and transfusion reactions are examples of what?
Antibody-mediated hypersensitivity (type II)
Type II reactions are mediated by IgG and IgM antibodies that react against antigens bound to specific cells or tissues. These antibodies interact with the Fc receptors on a range of effector cells
Mediators = IgM,IgG,Complement
anaphylactic reaction is an example of which type of reaction?
immediate hypersensitivity (type I)
Mediator = IgE
Viral systemic lupus erythematosus (SLE) and hepatitis and RA are examples of which type of reaction?
type III reaction
Mediators = IgG
Type IV examples
poison ivy (contact) and tuberculin / Mantoux test (delayed).
Graft rejection
Mediators = T-Cells
Which test is most sensitive in detecting pelvic inflammatory disease (PID)?
NAAT (polymerase chain reaction or strand displacement amplification) is more than 95% sensitive in detecting Chlamydia or Gonorrhoea from the endocervical specimen.
Which immunoglobulin has the highest molecular weight?
IGM
Weight = 900
First antibody type to be synthesized by neonates
Which immunoglobulin has the LOWEST molecular weight?
IGA
Weight =390
What proportion of cytomegalovirus (CMV) infections is asymptomatic in immune-competent patients?
CMV infection in adults is asymptomatic in 90% of cases
(f primary infection occurs in pregnancy, then there is a 40–50% risk of fetal transmission. Between 22% and 38% of the infected fetuses will develop symptoms.
3 types of lymphocytes:
B cell
T cell
Natural Killer Cells
Which cells form the adaptive immune system?
f B and T (Cd4) cell lymphocytes that have immune memory.
Type 5 reaction examples:
Myasthenia Gravis
Graves Disease
Mediators = IgM,IgG,Complement
Which term best describes the fetus?
Allograft
What does IGG do for the fetus?
Key to fetal immunity as crosses the placenta
At what stage of gestation does maternal immunoglobulin G transfer to the fetus start?
12 weeks
When does fetal production of IgM start?
Fetal productIon IgM starts around week 10 to 11.
What condition is decreased in pregnancy?
RA
Th1 suppression in pregnancy improves Rheumatoid arthritis
What condition worsens in pregnancy?
SLE
Increased Th2 activity by contrast results in higher rates of SLE flare ups
Which HLAs are upregulated/downregulated during pregnancy?
during pregnancy at the trophoblast:
HLA-A and HLA-B are downregulated
HLA-E and HLA-G are upregulated
Which complement protein recruits other complement proteins to form MAC (membrane attack complex)?
C5b
What are the rules for giving Anti-D?
- All RhD negative pregnant women who have not been previously sensitised should be offered routine antenatal prophylaxis with anti-D Ig (RAADP) either with a single dose regimen at around 28 weeks, or two-dose regimen given at 28 and 34 weeks
- Following birth, ABO and Rh D typing should be performed on cord blood and if the baby is confirmed to be D positive, all D negative, previously non-sensitised, women should be offered at least 500 IU of anti-D Ig within 72h following delivery.
- Following potentially sensitising events, anti-D Ig should be administered as soon as possible and always within 72h of the event.
- In pregnancies <12 weeks gestation, anti-D Ig prophylaxis is only indicated following ectopic pregnancy, molar pregnancy, therapeutic termination of pregnancy and in cases of uterine bleeding where there is repeated, heavy bleeding or associated with abdominal pain. The minimum dose should be 250 IU.
- For potentially sensitising events between 12 and 20 weeks gestation, a minimum dose of 250 IU should be administered within 72h of the event.
- For potentially sensitising events after 20 weeks gestation, a minimum anti-D Ig dose of 500 IU should be administered within 72h of the event. A test for FMH is required
Tumor markers:
Breast cancer = Ca27-29 AND Ca15-3
Peritoneal cancer = Ca-125
Pancreatic/Colon cancer = Ca19.9
Trophoblastic Disease = HCG
colorectal = CEA
Hepatocellular Cancer = AFP
Medullary carcinoma thyroid = Calcitonin
Live Vaccines:
BCG
MMR
Varicella
Polio (oral)
Inactivated vaccines:
Influenza
Hepatitis A
Pertussis
Toxoid Vaccines
Diptheria
Tetanus
Polysaccharide Vaccines:
HIB
Meningococcal A&C
Pneumococcal
Subunit/Genetically modified vaccines:
Hepatitis B
What is suppressed in pregnancy and aids immune tolerance of fetus?
Th1
Which complement protein is the product of all 3 activation pathways
The outcome of all 3 pathways is that C3 is cleaved into C3a and C3b.
Which cytokine has increased production during pregnancy and are thought to enhance fetal survival?
Interleukin 10
What cell type displays the rhesus antigen in Rhesus positive patients?
Erythocrytes
Which cell types act as professional antigen presenter cells (APCs)?
There are 3 types of professional APC’s
Dendritic Cells
Macrophages
B-Cells
Rhesus D immunoglobin treatment utilises what class of antibody?
IgG
