Device, system and method for detecting an analyte in a body fluid sample containing a plurality of cells

A device for detecting an analyte in a body fluid sample containing a plurality of cells, comprising:

• a sample input for receiving a body fluid sample (14) containing a plurality of cells;
• and an immunoassay unit comprising a detection surface for performing an immunoassay of said body fluid sample containing a plurality of cells, wherein said immunoassay unit comprises:
• an activating reagent for activating the plurality of cells contained in the body fluid sample to release an analyte, wherein the activating reagent refers to a molecule that is able to activate cells in order to release the analyte which is inside the cells contained in the body fluid sample without lysing the cells themselves;
• and
• an anti-analyte-antibody capable of binding to said analyte to form a complex comprising said anti-analyte-antibody and said analyte, wherein the forming of said complex proceeds at least partially simultaneous to the activating of said plurality of cells.