Upload
ken-myer-abansi
View
418
Download
3
Embed Size (px)
DESCRIPTION
Citation preview
Other Tests to detect Heterophile Antibodies1. Rapid Slide Tests that make use of slides or cards
rather than tubes
2. Formats that use solid phase to which antigen is affixed
Examples: ●Equipar
→ purified antigens from bovine red cells are coated onto latex particles
●Seradyn Color Slide II Mononucleosis test → aka Alexon Trend
→ use disposable cards and color-enhanced horse RBCs
KEN MYER ABANSI KEN MYER ABANSI
Anti-VCA IgM
Anti-VCA IgG
Anti-VCA IgA
Anti EA-D
Anti EA-R
Anti EBNA-IgG
Heterophile
No previous exposure
- - - - - - -
Recent( acute) infection
+ ++ +/- + - - +
Convalescent Period
- + - - +/- + +/-
Reactivation of latent infection
+/- + +/- +/- + +/-
Chronic active infection
- +++ +/- + ++ +/- -
Past Infection
- + - - - + -
No exposure , no Antigen stimulation, no Antibody production
appears during acute phase of infxn (IgM)
Persist 'til Convalescent Period
May/May Not be Produced
Marker ang IgG here
Positive only if VCA Ag is positive
Anti-VCA IgM
Anti-VCA IgG
Anti-VCA IgA
Anti EA-D
Anti EA-R
Anti EBNA-IgG
Heterophile
Post-transplant lymphoproliferative disease
- ++ +/- + + +/- -
Burkitt's lymphoma
- +++ - +/- ++ + -
Nasopharyngeal carcinoma
- +++ + ++ +/- + -
detect high titers good marker
detect high titers, good marker
EBV-specific Antibodies in I M* Anti-VCA IgM
→ usually detectable early in the course of infection, but low in concentration, disappears within 2-4 months
*Anti-VCA IgG → usually detectable within 4-7 days after onset of S/S
and persist for an extended period
*Anti-EA-D-IgG → highly indicative of acute infection , but not detectable
in 10-20% of patients with IM. It disappears in about 3 months; however a rise in titer is demonstrated during reactivation of latent EBV infection
EBV-specific Antibodies in I M
* Anti-EA-R-IgG → not usually found in young adults during acute phase.
Appears transiently in the later convalescent phase
*Anti EBNA IgG → appears only when the patient has entered the
convalescent period . Antibodies are almost always present in serum containing anti-VCA IgG unless the patient is in EA phase. Patients with severe immunologic defects or immunosuppresive disease may not have EBNA antibodies , even if VCA antibodies are present
EBV-specific Antibodies in I M
* Antibodies to NA remains at moderate measurable level indefinitely because of the persistent viral carrier state established after primary EBV infection
*Most healthy individuals have titers to EBNA ranging from 1:10-1:160
EBV-specific Antibodies in I M
*in EBV associated malignancies, the levels of EBNA antibodies are usually high in patients with nasopharyngeal carcinoma and variable in patients with Burkitt's lymphoma
EBV-specific Antibodies in I M
COMMON METHOD: Indirect Immunofluorescence PRINCIPLE: Antigen substrate slide containing EBV infected B-cells + patient serum incubate addition of fluorescent conjugated → →antihuman IgG or IgM
*ELISA to detect anti-EBNA, using asynthetic peptide Antigen to determine relative amounts of IgM and IgG antibodies in patient serum; reported with 99% specificity.