Immune mechanisms in patients with proven vascular disease.

Lymphocyte transformation and serum levels of immunoglobulins and complement were measured in groups of patients with old myocardial infarction, with peripheral vascular disease and in age- and sex-matched controls. There were no significant differences between the groups in phytohaemagglutinin (PHA) induced lymphocyte transformation, in IgA or in serum complement levels. The levels of IgG and IgM were significantly raised in patients with old proven infarcts while the level of IgM was raised in patients with peripheral vascular disease.