immunological tools Flashcards
Serology
detection of Ag+Ab complex
Serological techniques
when pathogen cannot be cultured, or is too dangerous to culture, or takes too long to grow
Interpretation of Serology
Detection of IgM:
current/recent infection
Detection of IgG: (ELISA)
- Four fold increase between acute and convalescent sera
- Above the Upper Limit of Normal (ULN)
Cellular techniques
Diagnosis made at the cellular level
Lymphocyte count/function
Immunodeficiency diseases
Macrophage activity
B cell T cell activation using mitogens
Skin test
Agglutination
Particulate antigen + soluble Ab
Require Optimum concentration of antigen antibody
in a test tube: semi-quantitative
on a slide: qualitative
Precipitin Reaction
Soluble Ag + soluble Ab
Labeled antibody assays
require monoclonal antibodies
Complement fixation
uses Ab coated RBC as a probe
Hemagglutinin
aggregates RBCs
Not antigen antibody reaction
Viral Hemagglutination
used in virus quantification
Agglutination Assay
RBCs ->
no reaction
RBCs + virus ->
Hemagglutination
RBC + virus + antibody ->
Hemagglutination inhibition
Coombs test
detects antibody against RBC
Coombs reagent
antihuman antibodies
Direct Coombs test
Detects RBC coated with Ab
ex. Rh of newborn
Indirect Coombs test
detects unbound (free)anti-RBC
ex. Rh in mother
Ouchterlony
Determine relationship between different antigens
Check purity of antigen preparations
(REVIEW PIC OF TEST - SLIDE 23)
Radial Immunoassay
Quantitative Assay
Ab mixed with the gel
Applications:
- Used to Quantify
- Serum immunoglobulins
- Blood clotting factors, complement components, CRP, etc
- Level of blood drug conc.
Immunoelectrophoresis
Qualitative
used for a qualitative analysis of complex mixtures of antigens
Countercurrent electrophoresis
only when Ag and Ab have opposite charges
Direct Fluorescent Ab (DFA)
antigen in patient’s tissue sample or any antigen on a solid surface
Indirect Fluorescent Antibody (IFA)
antibodies in patient’s serum
ELISA
detect either antigen or antibody in an unknown sample
semi quantitative test
Direct ELISA
Detects antigen
Indirect ELISA
detects antibody
Suppress immune system
anti TNF alpha
Chimeric mono ab
Engineered to reduce their immunogenecity
Complement Fixation Test
No lysis =
+ presence of ab in patient’s serum
Lysis =
Absence of ab in patient’s serum
Candida test
check deficiency in CMI
