Abstract We tried to apply Akaike's method of multivariate autoregressive modelling for analyzing immunologic networks in man. Autoregressive coefficients were obtained from clinically obtained chronologic data by means of a lest squares method and were used to compute Akaike's relative power contribution. By the analysis with this latter concept, it was suggested that, in a patient with systemic lupus erythematodes (SLE), slower components of the movements of T8+ lymphocytes are governed almost exclusively by those of T4+ lymphocytes, indicating the malfunction of T8 lymphocytes, including suppressor T-cells, in such a patient when compared to a normal control subject. The obtained autoregressive coefficients also enabled us to make a state space representation of the system under study and thereby to simulate an impulse response of the system in pathologic conditions. The present approach may provide a standardized method for analyzing immunologic networks in the body.