Digestive budget twin

9.3 to 30 um · low end human blood monocytes; upper end not attributable to a measurement · mean cell volume by Coulter counter, converted to a sphere-equivalent diameter · Nibbering PH et al. 1990, J Immunol Methods; upper end thin; see note for measured tissue diameters · source

The low end is not a macrophage diameter. Nibbering 1990 measured human blood monocytes at 421 fL in suspension, which is a sphere of 9.3 um, so that end is a monocyte volume converted to a diameter and not a measured macrophage. The 30 um upper end rests on a review statement rather than a measurement and is thin. The only measured human tissue macrophage diameters available are 14.2 um (carbon-negative) and 16.1 um (carbon-containing) in alveolar macrophages, from Baker J et al. 2025, ERJ Open Res (https://pubmed.ncbi.nlm.nih.gov/41189586/). Four cautions travel with those two numbers. The cohort is COPD patients and smokers and the same paper states COPD alveolar macrophages are larger than those of nonsmokers, so a healthy value would be lower. They are profile diameters measured on 4 um paraffin sections with no stereological correction stated, and a section through a cell is smaller than the cell unless it passes through the centre, so they underestimate. Those two errors run in opposite directions and neither is quantified here. And they sit below the 20 um threshold at which Szkalisity A et al. 2025, EMBO J (https://pubmed.ncbi.nlm.nih.gov/40195500/) excluded cultured human monocyte-derived macrophages as not yet differentiated, which is the evidence that a culture population and a tissue population are not the same cell and that the culture threshold must not be used as a floor for tissue. That paper is CC BY-NC: the licence restricts reuse of its figures, not citation of its numbers. EMPIAR-13420 segmentation will replace this whole row with a measured distribution.

0.8 to 8 um · human and mouse, review · fluorescence microscopy and review · Aderem A, Underhill DM 1999, Annu Rev Immunol · source

phagosome diameter matches the engulfed target: bacteria form ~0.8-1.5 um phagosomes; yeast 2-5 um; erythrocytes 6-8 um; see also Flannagan et al. 2012 (https://pubmed.ncbi.nlm.nih.gov/21910624/)

1 to 5 phagosomes · mouse (BALB/c), resident peritoneal macrophages, in vitro · derived: uptake rate 4.45 apoptotic cells/h (Licht 1999, PMID 10089102) combined with phagosome maturation time of minutes to tens of minutes (Flannagan 2012, PMID 21910624); no direct measurement of simultaneous phagosome count per macrophage found open-access · Licht R et al. 1999, J Immunol Methods · source

Derived slider, not a directly measured simultaneous phagosome count. Inputs: (1) uptake rate from Licht 1999 (PMID 10089102): 4.45 apoptotic thymocytes per macrophage per hour, with two taken within 10 min at peak; (2) phagosome maturation time from Flannagan 2012 (PMID 21910624): minutes to tens of minutes. Together these constrain the simultaneous load to 1 to 5. Moving the slider changes how many phagosome bodies are drawn inside the cell.

0 to 1 · mouse (BALB/c), resident peritoneal macrophages, in vitro · on/off trigger for the phagocytosis_apoptotic process; 1 = efferocytosis running at 4.45 apoptotic cells/h; 0 = process idle · Licht R et al. 1999, J Immunol Methods · source

Panel switch for the efferocytosis process. Set to 0 for a resting macrophage that is not actively engulfing; set to 1 to run the sourced rate (Licht 1999: 4.45 +/- 0.70 per h). Read back from step().processes.

1 to 5 cells · mouse (BALB/c), resident peritoneal macrophages, in vitro · in vitro phagocytosis assay; the maximal uptake observation (>5 per h) and near-simultaneous engulfment (2 within 10 min) constrain the number of available targets near the macrophage; in vivo densities in healthy tissue are not available open-access · Licht R et al. 1999, J Immunol Methods · source

Controls how many apoptotic target cells are drawn in the macrophage's environment. The range reflects the in vitro assay upper bound, not a measured tissue density.