Abstract: An immunoassay for assisting in the diagnosis of sepsis or severe infection in a patient/subject, the assay comprising the steps of: (i) optionally contacting a test sample comprising neutrophils from the patient with an agent that permeabilises or solubilizes neutrophils; (ii) simultaneously with (i) or sequentially, contacting the sample with a binding agent that binds specifically to CD64 in the sample and forms a CD64-binding agent complex a; (iii) simultaneously with (i) and/or (ii) or sequentially, contacting the sample with a second binding agent that binds specifically to a neutrophil number marker (NNM) in the sample and forms a neutrophil marker-binding agent complex b; (iv) employ the amount of complex a and complex b to determine the relative level of CD46 and of NNM in the sample.

Abstract: An immunoassay for assisting in the diagnosis of sepsis or severe infection in a patient/subject, the assay comprising the steps of: (i) optionally contacting a test sample comprising neutrophils from the patient with an agent that permeabilises or solubilises neutrophils; (ii) simultaneously with (i) or sequentially, contacting the sample with a binding agent that binds specifically to CD64 in the sample and forms a CD64-binding agent complex a; (iii) simultaneously with (i) and/or (ii) or sequentially, contacting the sample with a second binding agent that binds specifically to a neutrophil number marker (NNM) in the sample and forms a neutrophil marker-binding agent complex b; (iv) employ the amount of complex a and complex b to determine the relative level of CD46 and of NNM in the sample.