[Platelet immunoglobulins and complement in idiopathic thrombocytopenic purpura. Specificity to the IIb/IIIa membrane

M del Real Llorente1, F J Alvarez Guisasola

  • 1Departamento de Pediatría, Obstetricia y Ginecología, Facultad de Medicina, Valladolid.

Platelet-associated IgG, IgM and C3c was studied by an enzyme-linked immunosorbent assay (ELISA) procedure using polystyrene microter plates and solubilize platelets. At the time of investigation patients fell into the following disease categories: 24 chronic ITP, 10 acute ITP and 11 ITP in remission (normal platelet counts). A significant elevation of platelet IgG was found in acute and chronic ITP. The C3c was increased in acute categories and normal in the others. There was not significant difference in the immunoglobulins and complement values between ITP in remission and normal donors. The platelet specificity of IgG and IgM antibodies to IIb/IIIa membrane complex was positive in 20% from chronic ITP and in none from acute. It is concluded that an elevated platelet immunoglobulins or complement is usefull for ITP diagnosis but the difference between acute and chronic categories only is possible in some cases by the antibodies specificity.

Related Concept Videos

Phosphoinositides and PIPs01:42

Phosphoinositides and PIPs

Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Immunoprecipitation01:20

Immunoprecipitation

Immunoprecipitation, or IP, is a widely used technique that employs protein-antibody interactions to isolate proteins or protein complexes in their native state for studying protein-protein interactions, quaternary structures, or supramolecular complexes. Various modifications of the technique, including chromatin IP, cross-linking IP, and fluorescence IP, are commonly used.
Chromatin Immunoprecipitation
Chromatin immunoprecipitation, also known as ChIP, is used to study protein-DNA or...
Structure and Function of Platelets01:18

Structure and Function of Platelets

The cell fragments known as platelets are disc-shaped, with an average diameter of about 3 μm and a thickness of roughly 1 μm. They play a crucial role in the body's vascular clotting system, which also involves plasma proteins, blood cells, and blood vessel tissues.
Platelets are continually replenished, circulating in the bloodstream for 9-12 days before being removed by phagocytes, primarily in the spleen. A microliter of circulating blood contains between 150,000 and 450,000 platelets, with...
Formation of the Platelet Plug01:22

Formation of the Platelet Plug

The platelet phase, the second stage of hemostasis, commences around 15-20 seconds after an injury. It follows and overlaps with the vascular phase, during which blood vessels constrict to minimize blood loss.
As the injured blood vessel contracts, endothelial cells undergo contraction, revealing collagen fibers in the basement membrane and underlying connective tissue. Furthermore, the plasma membrane of endothelial cells becomes adhesive, preparing the site for platelet adhesion. Platelets...
Complement System01:27

Complement System

The complement system is a group of approximately 20 plasma proteins that strengthen the body's defenses against infections through opsonization, inflammation, and cell lysis. Opsonization involves coating pathogens with complement proteins, making them more recognizable and facilitating phagocyte engulfment. Certain complement proteins induce inflammation that attracts immune cells to the site of infection. Cell lysis involves the destruction of pathogens through the formation of a membrane...