Immunology Flashcards
Acetylcholine-receptor blocking antibodies
Myasthenia Gravis
Anti-myelin antibodies
Multiple Sclerosis
Anti-glomerular basement membrane Abs
Goodpasture’s syndrome
Anti-mitochondrial Abs
Primary Biliary Cirrhosis
Anti-smooth muscle Abs
Chronic Active Hepatitis
Anti-thyroglobulin and anti-microsomal (anti-thyroid peroxidase) Abs
Hashimoto’s Thyroiditis
⬆️ TSH
⬇️ T3,T4
Anti-TSH receptor Abs
Grave’s Dse
⬆️ T3,T4
⬇️ TSH
Play a role in CELL-MEDIATED IMMUNITY
T cells
Produce sensitized lymphocytes that secrete CYTOKINES
T cells
2/3 of peripheral T cells
CD4+ HELPER/INDUCER T CELLS
Normal value of CD4 CELLS
AND VALUE IN AIDS PX
N = 1000/uL AIDS = <200/uL
Other name for CD8 cells
Cytotoxic or Suppressor T cells
1/3 of peripheral T cells
CD8
Normal value CD4/CD8 RATIO
And in AIDS PX
N = 2:1 AIDS = <0.5:1
Differentiate into memory cells and plasma cells
B cells
Functions of B cells (2)
Humoral Immunity and Antibody formation
Percentage of Px with hashimoto’s thyroiditis that express ANTI-TPO
90%
Percentage of Px with hashimoto’s thyroiditis that express ANTI-THYROGLOBULIN
20-50%
OUCHTERLONY DIFFUSION PATTERNS:
Arc (smooth curve) indicates that the 2 antigens are IDENTICAL
Serological Identity
OUCHTERLONY DIFFUSION PATTERNS:
Two crossed lines represent two different pption rxns.
Antigens share NO IDENTICAL DETERMINANTS (intersect)
Non-identity
OUCHTERLONY DIFFUSION PATTERNS:
Ag 1 shares a determinant that is part of Ag 2 (not as complex); (SPUR)
Partial Identity
1st step in agglutination
Sensitization
Involves ag-ab combination through single antigenic determinants on the particle surface
Sensitization
2nd step in agglutination which is the formation or cross-links that form the visible aggregates.
Lattice formation
Step in agglutination that represents ag-ab complexes with the binding together of multiple antigenic determinants
Lattice formation
A rxn in which PARTICLES COATED WITH ANTIGENS not normally found on their surfaces clump together bc of combination with Ab
PASSIVE AGGLUTINATION
ANTIGEN to ANTIBODY
A rxn in which CARRIER PARTICLES COATED WITH ANTIBODY clump together bc of a combination with Ag
(AB TO AG)
Reverse-Passive Agglutination
Determines IN VIVO attachment of Ab or complement to RBCs, using AHG = visible agglutination rxn
DIRECT AHG TEST (DAT)
Often uses as the 1st line DAT; detects RBCs with either IgG/Ig3 bound to them
Polyspecific AHG
Positive test with anti-IgG;
Autoab bound in vivo to px’s RBCs,
Alloab to transfused RBCs,
Maternal ab bound to NEONATAL RBCs.
Monospecific AHG ANTI-IgG
Positive test with Anti-C3:
IgG: Capable of binding the c’- usually IgG+
IgM: cold-reactive autoab
Monoclonal AHG ANTI-c3d
Purpose of washing RBCs in DAT
To remove any unbound Ab
Added to validate a negative result in DAT
Coomb’s control cells
When IgG Abs are detected, what should the MT do next?
DISSOCIATE abs from the RBC surface to allow for ID
Are used to RELEASE, CONCENTRATE and PURIFY Abs
Elution techniques
Changes caused by methods used to remove Ab cause? (3)
- thermodynamics of the environment;
- Attractive forces between Ag and Ab;
- Structure of the RBC surface
Dissociates IgG from RBCs with little or no damage to the RBC membrane
Chloroquine Diphosphate
2 rgts useful in stripping Ab from the RBC surface, while leaving the membrane INTACT to allow PHENOTYPING
Chloroquine Diphosphate and ACID GLYCINE (EDTA)
Positive result for COOMB’S CTRL CELLS/CHECK CELLS
Agglutination
Potential reasons for a false-negative result in DAT (No agglutination with Check Cells - INVALID) -(3)
- Failure to add the antiglobulin rgt to test
- Failure of the added antiglobulin rgt to react
- Failure to wash RBCs adequately
Measurement of TOTAL IgE
RIST
Determining Specific IgE
RAST/FAST
RPR: NR
VDRL: Reactive
Late, latent or previous syphilis
Immune status evaluation
Rubella: women of childbearing age;
Syphilis Testing: obtain marriage license;
CMV: transplant donor & recipient
Immunologic manifestation of HAV infxn
Stool HAV ➡️ IgM anti-HAV (acute) ➡️ IgG anti-HAV (Immunity)
An excellent indicator of chronicity in hepatitis infxn
PERSISTENCE OF SURFACE ANTIGEN
Chronic infxn: surface Ab does not appear, surface Ag persists
2 diseases caused by HTLV-I
- Adult T-cell Ieukemia/lymphoma (ATL)
2. HLTV-associated myelopathy/Tropical spastic paraparesis (HAM/TSP)
Screening test for HTLV
ELISA (if + retested by ELISA)
Confirmatory test for HTLV
Western Blot
Detectable within DAYS of HIV infxn
VIRAL RNA
Detectable in 2-3wks; Undetected when Abs develop; becomes detectable AGAIN in LATE STAGES (Immune system fails; Virus replicates)
p24 Ag
Detected, peaks and becomes undetectable: IgM (HIV)
D: 2-8wks
P: 1-2wks
UD: 1-2wks later
Detected and increase: IgG Ab (HIV)
D: shortly after IgM
Gradual increase on titer over SEVERAL MONTHS.
LONG LASTING
Confirmatory for HIV
Western Blot
Reasons why Western blot is not recommended for initial screening (3)
- Labor intensive
- Relatively insensitive
- Long TATB
Positive for WESTERN BLOT (HIV)
At least 2/3 bands present:
p24, gp41, gp120/gp160
If an INDETERMINATE TEST RESULT IS OBTAINED IN HIV WESTERN BLOT, it is recommended that
Test be repeated with the same or a fresh specimen
Used for improved specificity in detecting LYME DSE
Western Blot
Aids in dx of Congenital Toxoplasmosis (newborns)
Detectable IgM antibody (newborns);
Supported with the presence of ⬆️ IgM titers in the mother’s serum
Mental retardation, most have large head size, prominent ears, jaw and macro-orchidism
Fragile X syndrome
Molecular dx of Fragile X syndrome
SOUTHERN BLOT OR METHYLATION ANALYSIS
