In addition, our group has previously shown changes associated with asthma in the serum levels of many of the proteins detected in urine, i.e., IGFALS, FCN2, HSPG2, CD26/DPP4, and CD14, and suggested their use as potential phenotype/severity biomarkers of this disease [58,59,60,61,62]. Here, FCN2 is linked to asthma.