Abstract: The present invention relates to a method for analysing exogenous and endogenous cell activation where the assembly of receptors in a receptor cluster comprising CD14 is measured. Preferably, this takes place by measuring the energy transfer between the individual receptors, measurement by means of fluorescence resonance energy transfer (FRET) being preferred. The present invention further relates to a method for diagnosing systemic inflammations such as sepsis, arteriitis or autoimmune diseases or an arteriosclerotic or inflammatory disease of the coronary arteries (CAD, for example angina pectoris, cardiac infarction or coronary scleroses) or of the cerebral arteries (such as a stroke) or a precursor of any of these diseases which is based on the measurement of the assembly of receptors in a receptor cluster comprising CD14, as well as the use of compounds preventing clustering of CD14 to treat these diseases.