Cellular and Humoral Immune Responses to Vascular Components in Thromboangiitis Obliterans

Abstract

Cellular and humoral immune responses to vascular components were stud ied in 10 patients with thromboangiitis obliterans (TAO), including 3 in the mild stage of the disease and 7 in the active or severe stage. In this study the authors used the following vascular components: collagen Types I, III, IV, and V; elas tin ; and laminin. The cell-mediate reactivity (CMR) to these proteins was mea sured with an antigen-specific proliferation of peripheral mononuclear cells and evaluated by the stimulation index (SI), which is the ratio of thymidine incorpo ration in the presence and in the absence of antigen. The humoral immunologic response (HIR) to these vascular components was measured by an enzyme- linked immunosorbent assay (ELISA) and evaluated by the optical density (OD) index, which is the ratio of optical density (OD) in the patients' serum to that in the healthy male controls' serum. The stimulation index of collagen Types I and IV was significantly higher in patients with TAO than in healthy controls (p < 0.02). CMR to collagen Type V, elastin, and laminin was high in patients with active or severe TAO as well. However, similar statistical differences in mild TAO did not exist in the CMR. The OD index in collagen Types I, IV, and V was statistically higher in the patients than in the healthy controls (p < 0.01). These autoimmune epiphenomena to vascular components in TAO suggest that autoimmune mechanisms are related to vasculitis of TAO patients. When it is considered that CMR was found in active or severe TAO, but not in mild TAO, CMR does not seem to be the initiator of vasculitis. These differences in immune reactivities suggest that the autoimmune epiphenomena to the vascular components might be related to the exacerbation and perpetuation of TAO.