FGFR1 and COVID-19: Apart from these, the meta-analysis further clarified the direction of the alteration of other proteins with potential biological relevance in COVID-19, such as the decrease in the soluble blood levels of the receptors for the colony-stimulating factor 1 (CSF1R) and fibroblast growth factor (FGFR1), likely due to their internalisation after binding their ligands.