Fig. 9: Proposed working model: neutrotime as the central organizing principle of neutrophil heterogeneity.

Healthy neutrophils are organized along one main sequence, termed neutrotime, from which they deviate as a function of time and environmental cues to reach different polarization states, orchestrated by shared and context-specific transcription factors. Experimental inflammation was found to recruit neutrophils predominantly near the mature pole of neutrotime; however, deviation from points earlier in the spectrum is also likely, reflected in arrows all along the neutrotime continuum. The colors of cells polarizing into different states illustrate that some features of the neutrotime sequence are maintained.