“New” Antigenic Targets and Methodological Approaches for Refining Laboratory Diagnosis of Antiphospholipid Syndrome

Table 1

Different technical approaches for aPL detection.

Assays	Technical characteristics	Main antibodies detected	References
ELISA	Protein and/or PL/protein complex coated on surface of polystyrene plates microtitre wells	Anti-CL/β2-GPI (IgG, IgM, IgA); Anti-PE; Anti-β2-GPI (IgG, IgM, IgA); Anti-β2-GPI-DI; Anti-vimentin/CL; Anti-PT/PS; Anti-AnnA5; Anti-AnnA2	[6, 9, 10]; [67–69]; [39, 40, 42, 43]; [31–36]; [51–55]; [11, 47–50]; [41]; [16, 22, 41, 56–59]
Chemiluminescence	Antigenic presentation of proteins and/or PL/protein complex on magnetic particles; Binding on this solid phase determines peculiar density, orientation, and conformational changes of antigenic epitopes	Anti-CL/β2-GPI; Anti-β2-GPI	[81–87]
Dot blot	Phospholipid or proteins immobilized onto PVDF membranes: these hydrophobic membranes offer a distinct reaction environment, hiding hydrophobic phospholipid groups and exposing hydrophilic part	Anti-PL; Anti-protein cofactors	[88–91]
TLC immunostaining	Antigens run on aluminum-backed silica gel plates mimicking the exposure of phospholipid to binding proteins Chromatograms are incubated with sera and finally immunoreactivity is assessed by chemiluminescence reaction	Anti-PL	[50, 98–101]

aPL: anti-phospholipid antibodies; anti-CL: anti-cardiolipin antibodies; anti-β2-GPI: anti-beta2-glycoprotein I antibodies; anti-β2-GPI-DI: anti-beta2-glycoprotein I antibodies domain I antibodies; anti-PT/PS: anti-prothrombin/phosphatidylserine antibodies; anti-vimentin/CL: anti-vimentin/cardiolipin antibodies; anti-AnnA5: anti-annexin A5 antibodies; anti-AnnA2: anti-annexin A2 antibodies; anti-PE: anti-phosphatidylethanolamine antibodies; PVDF: polyvinylidene difluoride membranes; TLC: thin layer chromatography.