Read alongside membrane integrity
Annexin V positivity with a negative membrane-integrity dye can be consistent with early apoptosis. Double positivity indicates compromised membranes but does not distinguish late apoptosis from other cell death. Use unstained and single-stain controls to establish separation and positivity thresholds.
Check timing and supporting evidence
Compare samples at matched treatment times and add caspase activity, morphology or another relevant readout. Report the membrane-integrity dye, gating boundaries and acquisition timing so positive fractions can be compared.
Interpret with membrane integrity
Define the gated population and exclude debris, obvious doublets and acquisition artifacts first. The table describes common interpretations; the death mechanism also requires treatment timing and independent markers.
| Annexin V | Membrane-integrity dye | Common interpretation |
|---|---|---|
| Negative | Negative | No detected PS exposure or increased membrane permeability |
| Positive | Negative | Accessible PS with exclusion of the integrity dye; consistent with early apoptosis |
| Positive | Positive | Compromised membranes; distinguish late apoptosis from other death processes |
| Negative | Positive | Review membrane damage, binding buffer and staining; this state alone does not establish a death mechanism |