IIF rodent tissue | Subjective, Ro may be missed, semiquantitative, pattern not diagnostic, cannot detect cell cycle related patterns, not specific | Cheap, can be isotype specific | Semiquantitative end point titration or qualitative result at screening titre + pattern |
IIF HEp-2 | Subjective, Ro may be missed, semiquantitative (poor precision), pattern not diagnostic, not specific | Cheap, recombinant Ro60 expression to boost Ro sensitivity available, can be isotype specific | Semiquantitative end point titration or qualitative result at screening titre + pattern |
Ouchterlony double diffusion (ID) | Slow, crude antigens, subjective, qualitative, requires experience, not isotype specific, some false negatives | Specific, cheap | Positive or negative + antigen specificity |
Countercurrent immunoelectrophoresis (CIE) | Slow, crude antigens, semiquantitative, requires experience, not isotype specific, some false negatives | As ID, but more sensitive | Positive or negative + antigen specificity |
Haemagglutination | Detects IgG and IgM, semiquantitative, subjective, detects low affinity antibodies | Cheap | Positive or negative + semiquantitative titre |
Immunoblotting (IB) | Qualitative, may be insensitive for Ro, crude antigen, labour intensive | Sensitive, very specific for individual antigens | Positive or negative + antigen specificity |
Immunoprecipitation (Farr) | Radioactive, labour intensive, expensive, technically difficult, no isotype specificity, false positivity | Quantitative, high specificity, detects high affinity antibodies | Quantitative result, potentially in standardised IU/l if reference preparation available |
ELISA | Detects low affinity antibodies, needs high purity well defined antigens (native v recombinant), false positivity | Sensitive, variable, can be polyspecific or IgG specific | Qualitative or quantitative results, potentially in standardised IU/l if reference preparation available |