SPP1 and asthma: Interestingly, previously thought as an exclusively eosinophilic biomarker, ECP was found also to be elevated in neutrophilic asthma in the absence of eosinophils, and osteopontin, which was regarded as a T1-biomarker, was found to be elevated in asthma in general, but could not be used to differentiate between phenotypes, showing that future investigations could change old dogmas [74,75].