Endothelial cell antibodies

A heterogeneous group of antibodies directed to antigenic determinants of endothelial cells. Anti-endothelial antibodies cross-react with IgG- and IgM-class cardiolipin antibodies and platelet antibodies.

Antibodies to the endothelium have been found in many primary vasculitides and vasculopathies. They are relatively common in Kawasaki disease, aortoarteritis Takayasu granulomatous vasculitis, Schoenlein-Genoch purpura, and secondary vasculopathies, particularly obliterative thrombangiitis (Buerger's disease) hemolytic thrombocytopenic purpura, and antiphospholipid syndrome.

Anti-endothelial antibodies are associated with the activity of a number of vasculitides and vasculopathies, including ANCA-associated vasculitis, particularly Kawasaki disease, obliterative thrombangiitis. They occur in 50% of patients In Behçet's syndrome, especially in patients with severe cutaneous vasculitis.

The detection expediency of this type of autoantibodies in the clinic is determined by their appearance against the background of pronounced clinical activity of the disease, which allows us to focus on their content to determine the phase of the disease. They may play a certain role in the pathogenesis of vasculitis due to the fact that they are able to modulate the expression of endothelial adhesion molecules and inflammatory factors. AETAs detected in the serum of SLE patients are able to enhance the release of IL-6 from endotheliocytes, thus participating in the pathogenesis of the systemic inflammatory response.

Today, criteria for determining anti-endothelial antibodies in the clinic have not been definitively developed. Antibodies to endothelium can serve as a nonspecific marker of angiopathies of various genesis, and monitoring of their content in the patient's blood serum over time allows to establish the activity of the pathological process affecting blood vessels.

Vasculitis and vasculopathies against the background of systemic connective tissue diseases are accompanied by high titers of antibodies to endothelium. In SLE, frequency of anti-endothelial antibodies ranges from 30 to 80%, depending on the method used and the group of patients. In patients with SLE, when high antibody titers are detected, cutaneous manifestations of vasculitis and severe Raynaud's syndrome are more often noted. The majority of patients with lupus nephritis and hypocomplementemia have high titers of antibodies to endothelium, which, apparently, is due to the ability of autoantibodies to directly interact with renal tubular epithelial cells. The content of AETA decreases with successful immunosuppressive therapy.

Scleroderma is usually accompanied by signs of generalized vasculopathy. It is assumed that one of the causes of microangiopathy in scleroderma may be antibodies to the endothelium, which are observed in 30-40% of patients. Anti-endothelial antibodies in diffuse forms of scleroderma are associated with a high risk of lung damage, characterized by the development of interstitial fibrosis and pulmonary hypertension.

There is a definite association between antiphospholipid and anti-endothelial antibodies. AETAs are frequently noted in patients with antiphospholipid syndrome, miscarriage of pregnancy, and idiopathic liveto. Antigens of anticardiolipin antibodies, particularly complexes of phospholipids and beta2-glycoprotein 1 are able to bind to the surface of endothelial cells, leading to endothelial damage. In women with a history of recurrent miscarriage and presumed antiphospholipid syndrome, antibodies to the endothelium are also found. The presence of antibodies is characteristic of secondary angiopathies, particularly diabetic microangiopathy and vascular graft rejection. Detection of antibodies to endothelium is relatively nonspecific for a particular form of vasculitis and is considered as a general diagnostic marker of large vessel vasculitis and vasculopathies.