Use this calculation for cell-culture or microscopy observations collected with one counting rule, assay gate, calibration, and unit convention. It is suited to documenting dilution, growth, labeling, geometry, or population fractions.

Initial passage

An integer count greater than or equal to 0.

Splits performed

An integer count greater than or equal to 0.

The implementation follows this calculation rule: Compute the current cell passage number from the initial passage and splits.

Current passage number

The calculated current passage number.

Counts and fluorescence measurements can be biased by clumping, debris, segmentation, gating, background signal, saturation, sampling fields, or unequal viability. A calculated percentage does not identify the biological mechanism behind a change. Preserve the input values and units so the result can be audited and recalculated.

Retain representative images or cytometry plots and include biological replicates. Orthogonal viability, proliferation, apoptosis, or direct counting assays can distinguish effects that a single cell metric conflates.

• CFSE Dilution Factor

  Estimate cell division count from CFSE fluorescence dilution using the base two logarithm of the initial over current intensity.

• CFSE MFI Halving

  Infer the number of CFSE fluorescence halvings, and hence cell generations, from parent and current mean fluorescence intensities.

• Doubling Time (PDT)

  Calculate population doubling time as elapsed hours times ln(2), divided by ln(final count / initial count).