In addition, ELISA assay for measurement of IL-12p40, IL-12p70 and IFN-γ after stimulation of whole blood or peripheral blood mononuclear cells (PBMCs) with stimulation conditions comprising live BCG stimulation at a multiplicity of infection of 20 (BCG/leukocytes) with or without hrIL-12p70 (20ng/mL), or hrIFN-γ (5000 IU/mL) co-stimulation for 18h (for IL-12 measurement) or 48h (for IFN-γ and IL-12 measurements), could be used to differentiate between immune defects due to IFN-γ production or IFN-γ response (9). Here, IFNG is linked to infection.