Inmunopatogenia de las arteritis de grandes vasos / Immunopathogenesis of arteritis of large vessels

La vasculitis es un proceso anatomo-clínico caracterizado por la inflamación y lesión de los vasos sanguíneos. La arteritis de células gigantes y la arteritis de Takayasu se clasifican dentro de las vasculitis de grandes vasos. Ambas se caracterizan por la formación de granulomas. Los linfocitos T CD4 dirigen el daño a los tejidos como un sine qua non en el proceso vasculítico; la activación de los linfocitos T en el ambiente no linfoide de las paredes arteriales requiere la activación de las células dendríticas. Como consecuencia, la activación de monocitos y macrófagos es responsable de un síndrome sistémico inflamatorio. El resultado final es una vasculopatía oclusiva causada por una rápida proliferación de la íntima (arteritis de células gigantes) o la formación de un aneurisma causado por la destrucción de la pared arterial (arteritis de Takayasu).

Vasculitis is a clinical anatomic process characterized by inflammation, and blood vessel damage. Giant cell arteritis and Takayasu arteritis are classified into large-vessel vasculitis. Both are characterized by the formation of granulomas. CD4 T cells direct the tissue damage as a sine qua non in the vasculitic process; activation of T cells in the nonlymphoid environment of the arterial walls requires activation of dendritic cells. As a result, the activation of monocytes and macrophages is responsible for a systemic inflammatory syndrome. The end result is an occlusive vasculopathy caused by a rapid proliferation of the intima (giant cell arteritis), or the formation of an aneurysm caused by the destruction of the arterial wall (Takayasu arteritis).

Effect of endothelial cells on the lymphoproliferative response in Takayasu's arteritis.

Takayasu's arteritis, also known as 'non-specific aortoarteritis' is an inflammatory disease of the aorta and its major branches. It also involves the pulmonary artery. The aetiology of the disease is not known so far. Abnormalities of the endothelial cells in terms of their structure and function are seen in the pathology of a number of diseases affecting the blood vessel wall. However, involvement of the endothelial cells in non-specific aortoarteritis is not known. In an effort to identify the role of endothelial cells in the pathogenesis of Takayasu's arteritis, peripheral blood lymphocytes isolated from the blood of patients suffering from Takayasu's arteritis were cultured in the presence of endothelial cells alone and in the presence of mitogens concanavalin-A and phytohaemagglutinin-P. The peripheral blood lymphocytes of patients with Takayasu's arteritis showed a significantly decreased blastogenic response to the mitogen concanavalin-A when cultured in the presence of endothelial cells. Our result thus suggests that endothelial cells may probably induce an inhibitory effect on the lymphocytes in patients with Takayasu's arteritis.

Avaliaçäo clínica em 123 pacientes com anticorpo antifosfolopídio / Clinical evaluation of 123 patients with antiphospholipid antibodies

A síndrome de anticorpos antifosfolipídios é um distúrbio adquirido das proteínas sangüíneas associadas aos quadros trombóticos, aborto de repetição e trombocitopenia. Uma série de manifestações clínicas diversas tem sido associadas a estes anticorpos e o presente estudo descreve os achados observados no hospital de Base no período de 1993 a 1995 em 123 pacientes com positividade para estes anticorpos do quais em 82 constatou-se um quadro trombótico em 18, abortos de repetição, e em 23 manifestações diversas como no lúpus eritematoso sistêmico, cardiopatias, livedo reticular, tireoidite de Hashimoto, doença de Takayassu e outras. Os anticorpos antifosfolipídios representam uma freqüente condição trombogênica merecendo uma investigação mais sistemática nos quadros trombóticos e de abortos de repetição onde uma causa aparente não é detectada.