FIELD : medicine.SUBSTANCE : invention relates to medicine, in particular to clinical immunology, and can be used to assess the lytic activity of multiply modified low-density lipoproteins. Method involves preparing a precipitate from human serum by incubating the supernatant obtained after preliminary precipitation of multiple modified low-density lipoproteins (mmLDL) with buffer containing 20?% polyvinylpyrrolidone with a molecular weight of 35, 000 (PVP-35000) for 30 minutes at 4?癈. Then the formed aggregates of immune complexes containing mmLDL (IC-mmLDL) are precipitated by centrifugation at 4?癈 for 10?min at 31, 000?g, decanted, the resulting precipitate is dissolved in buffer without PVP-35000 and the cholesterol content in immune complexes is determined. Standardized erythrocytes of ram are added to samples of mmLDL and IC-mmLDL, incubated for 24 hours at 37?癈, the coefficient of specific lytic activity (CSLA) of mmLDL and IC-mmLDL is calculated as the ratio of the degree of lysis to cholesterol in these complexes, the values of CSLA of mmLDL and IC-mmLDL are compared in the examined person. In the case of a decrease in this coefficient, IC-mmLDL compared with CSLA mmLDL is estimated as neutralization of lytic activity. With the opposite effect, with a tendency to increase of this coefficient of IC-mmLDL, is estimated as an increase in lytic activity. Equal values of CSLA (mmLDL) and CSLA (IC-mmLDL) indicate that autoantibodies, binding to mmLDL in immune complexes, do not affect lytic activity.EFFECT : use of this invention allows to evaluate the nature of the autoimmune reaction of the body to mmLDL for early prediction of the course and monitoring the effectiveness of pathogenetic therapy of atherosclerosis.1 cl, 1 ex, 7 tbl, 1 dwg