Question 1

Why is the vaccination challenge assay treated as the definitive test?

Accepted Answer

Damage signals indicate that the machinery is engaged, but only protection in a live host shows that the dying cells actually primed immunity. Injecting treated cells into an immunocompetent animal and challenging with viable tumour cells on the opposite flank measures the outcome that matters. A non-immunogenic death control defines what protection means in that setting.

Question 2

How should surface calreticulin be measured correctly?

Accepted Answer

Staining must be performed on unpermeabilised cells with a viability marker included, since dying cells with compromised membranes admit antibody and produce signal from the far larger internal pool. Reporting the fraction of viable-gated cells positive at the surface, at several time points, separates genuine exposure from artefact.

Question 3

Why is ATP release difficult to quantify?

Accepted Answer

Extracellular ATP is short-lived and degraded rapidly by surface ectonucleotidases, so a single late measurement usually finds nothing. Frequent sampling, or biosensor approaches reading concentration continuously, capture the release window. Including an inhibitor arm confirms that low readings reflect breakdown rather than absent release.

Question 4

Which control death modality should comparisons use?

Accepted Answer

Freeze-thaw necrosis is the conventional non-immunogenic reference, and agents known not to trigger the pathway serve as treatment-matched controls. Both arms should deliver similar numbers of dying cells at a comparable stage, since differences in death extent rather than death quality would otherwise explain any protection observed.

Question 5

What model systems are appropriate for this work?

Accepted Answer

Syngeneic tumour lines in immunocompetent hosts are required, since the readout depends on an intact adaptive response. Line choice matters because antigenicity varies widely and poorly antigenic models can appear negative regardless of death mechanism. Characterising baseline immunogenicity of the chosen line makes negative results interpretable.

Question 6

How does this connect to checkpoint blockade combinations?

Accepted Answer

The rationale is that priming supplies the T cells that checkpoint inhibition then sustains, so the death-inducing agent and the antibody are expected to act sequentially rather than simultaneously. Testing several schedules, and profiling the tumour immune infiltrate at each, distinguishes real synergy from additive cytotoxicity.

Biotechnology

Biotechnology

Research Frontiers in Immunogenic Cell Death Induction