DISTINGUISHING CELLS IN A SAMPLE BY INACTIVATING EXTRACELLULAR ENZYME BEFORE RELEASING INTRACELLULAR ENZYME

摘要

A method for detecting the absence or presence of cells of interest in a liquid sample, wherein: (a) the sample: (i) comprises an extracellular medium containing an enzyme with a measurable activity; and (ii) is suspected of containing cells of interest that contain an enzyme with said measurable activity; and (b) the method comprises the steps of: (i) treating the liquid sample with a reagent that inactivates said measurable activity in the extracellular medium, but does not inactivate the measurable activity in said cells of interest; (ii) lysing the cells of interest to release the intracellular enzyme; and (iii) measuring said measurable activity. Thus the intracellular enzyme can be measured without interference from the extracellular enzyme. The invention is particularly useful for treatment of bacterially-infected blood using a detection assay based on adenylate kinase activity.