Biomaterial Database

Platelet immunology. ELISA for detection of platelet antibodies, platelet-specific antigens and platelet glycoproteins. 1992

E Taaning

Department of Clinical Immunology, Glostrup Hospital.

The development of an enzyme linked immuno-sorbent assay (ELISA) for detection of platelet antibodies and platelet specific-antigens has been described. In the assay, intact platelets fixed to the bottom of microplates have been used as targets. After incubation with serum, the attached antibody has been detected by antiglobulin serum labelled with enzyme followed by assay of the enzyme reaction with its substrate. The clinical significance of platelet antibodies in alloimmune neonatal thrombocytopenia (AINT), post-transfusion purpura (PTP), and refractoriness to platelet transfusion therapy has been described. The clinical significance of autoantibodies in autoimmune thrombocytopenic purpura (AITP) and the detection of platelet surface glycoproteins by a modification of the platelet ELISA has also been described. In addition, a survey of the present state of knowledge of human platelet immunology, especially platelet-specific alloantigens and alloantibodies has been given. The studies of AINT and PTP have revealed a human immune response gene located in the MHC region: The susceptibility to anti-Zwa alloimmunization is strongly associated with the HLA-B8 and even more DR3 and DRw52a tissue types. In the studies of PTP, the first example of PTP due to anti-Zwb (only detectable in the platelet ELISA) has been described, and an association of the presence of anti-Zw antibodies of IgG3 subclasses (defined in the platelet ELISA using monoclonal mouse antibodies) and destruction of autologous platelets has been described. In an investigation of Ig classes and IgG subclasses of platelet associated Ig (PAIg) in children suffering from autoimmune thrombocytopenic purpura, no correlation was found between the immunochemical properties of the PAIg and the clinical course of the disease. However, a correlation between increased amounts of PAIgG3 and very low platelet counts was observed. A modification of the platelet ELISA using monoclonal antibodies against glycoproteins (GP) has been described. Using antibodies against GPIb and GPIIb/IIIa, it has been possible to diagnose Glanzmann's thrombasthenia (GT) and Bernard-Soulier syndrome (BSS). Especially in the diagnosis of thrombocytopenic patients suspected for BSS where platelet aggregation studies has been impossible due to low platelet counts, the detection of decreased amounts of surface GPIb in ELISA has been of great value. In conclusion, the platelet ELISA has been found simple and sensitive, and suitable for routine investigations of AINT, PTP, AITP, and refractoriness to platelet transfusion.

UI	MeSH Term	Description	Entries
D007518	Isoantibodies	Antibodies from an individual that react with ISOANTIGENS of another individual of the same species.	Alloantibodies
D007519	Isoantigens	Antigens that exist in alternative (allelic) forms in a single species. When an isoantigen is encountered by species members who lack it, an immune response is induced. Typical isoantigens are the BLOOD GROUP ANTIGENS.	Alloantigens,Alloantigen,Isoantigen
D010980	Platelet Membrane Glycoproteins	Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.	PM-GP,Platelet Glycoprotein,Platelet Membrane Glycoprotein,PM-GPs,Platelet Glycoproteins,Glycoprotein, Platelet,Glycoprotein, Platelet Membrane,Glycoproteins, Platelet,Glycoproteins, Platelet Membrane,Membrane Glycoprotein, Platelet,Membrane Glycoproteins, Platelet,PM GP
D001792	Blood Platelets	Non-nucleated disk-shaped cells formed in the megakaryocyte and found in the blood of all mammals. They are mainly involved in blood coagulation.	Platelets,Thrombocytes,Blood Platelet,Platelet,Platelet, Blood,Platelets, Blood,Thrombocyte
D004797	Enzyme-Linked Immunosorbent Assay	An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.	ELISA,Assay, Enzyme-Linked Immunosorbent,Assays, Enzyme-Linked Immunosorbent,Enzyme Linked Immunosorbent Assay,Enzyme-Linked Immunosorbent Assays,Immunosorbent Assay, Enzyme-Linked,Immunosorbent Assays, Enzyme-Linked
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000939	Epitopes	Sites on an antigen that interact with specific antibodies.	Antigenic Determinant,Antigenic Determinants,Antigenic Specificity,Epitope,Determinant, Antigenic,Determinants, Antigenic,Specificity, Antigenic
D013921	Thrombocytopenia	A subnormal level of BLOOD PLATELETS.	Thrombopenia,Thrombocytopenias,Thrombopenias
D016553	Purpura, Thrombocytopenic, Idiopathic	Thrombocytopenia occurring in the absence of toxic exposure or a disease associated with decreased platelets. It is mediated by immune mechanisms, in most cases IMMUNOGLOBULIN G autoantibodies which attach to platelets and subsequently undergo destruction by macrophages. The disease is seen in acute (affecting children) and chronic (adult) forms.	Autoimmune Thrombocytopenic Purpura,Idiopathic Thrombocytopenic Purpura,Purpura, Thrombocytopenic, Autoimmune,Werlhof's Disease,Autoimmune Thrombocytopenia,Immune Thrombocytopenia,Immune Thrombocytopenic Purpura,Thrombocytopenic Purpura, Autoimmune,Werlhof Disease,Autoimmune Thrombocytopenias,Autoimmune Thrombocytopenic Purpuras,Disease, Werlhof,Disease, Werlhof's,Idiopathic Thrombocytopenic Purpuras,Immune Thrombocytopenias,Immune Thrombocytopenic Purpuras,Purpura, Autoimmune Thrombocytopenic,Purpura, Idiopathic Thrombocytopenic,Purpura, Immune Thrombocytopenic,Purpuras, Autoimmune Thrombocytopenic,Purpuras, Idiopathic Thrombocytopenic,Purpuras, Immune Thrombocytopenic,Thrombocytopenia, Autoimmune,Thrombocytopenia, Immune,Thrombocytopenias, Autoimmune,Thrombocytopenias, Immune,Thrombocytopenic Purpura, Idiopathic,Thrombocytopenic Purpura, Immune,Thrombocytopenic Purpuras, Idiopathic,Thrombocytopenic Purpuras, Immune,Werlhofs Disease