Question 1

Why do most patients not respond durably to blockade?

Accepted Answer

Blockade releases a brake but cannot create a response that was never mounted. Tumours with few recognisable antigens, absent lymphocyte infiltration, defective antigen presentation or a suppressive microenvironment give nothing to release. Distinguishing these situations matters, because each implies a different combination strategy rather than a stronger blocking agent.

Question 2

Which preclinical model should carry the conclusions?

Accepted Answer

Syngeneic tumours in immunocompetent animals have an intact immune system but respond more readily than human disease and use surrogate reagents. Humanised models allow human-directed agents while reconstituting only part of the immune compartment. Human tissue explants preserve the real microenvironment briefly. State plainly what the chosen model cannot address.

Question 3

How is on-target activity established for a new agent?

Accepted Answer

Measure binding affinity and epitope, confirm blockade or engagement of the ligand interaction directly, and show functional consequences in assays with defined stimulation. Receptor-deficient cells or animals provide the decisive control, since an agent showing identical activity without its target is acting through something else entirely.

Question 4

Why has expression alone failed as a predictive marker?

Accepted Answer

Ligand expression varies between tumour regions, changes over time, and differs by antibody clone and scoring method. It also appears on immune cells as well as tumour cells, with different implications. Composite measures combining infiltration patterns, antigenic load and inflammatory gene signatures perform better but still require prospective testing.

Question 5

How should resistance be studied in a doctoral project?

Accepted Answer

Paired sampling before treatment and at progression is far more informative than cross-sectional comparison. Profile infiltrating populations by sequencing and imaging, examine antigen presentation machinery, and check whether other inhibitory receptors have risen. Distinguish primary non-response from acquired resistance, since the mechanisms and implications differ.

Question 6

What differs when strengthening inhibitory signalling for autoimmunity?

Accepted Answer

The goal reverses: engage rather than block, and restrain the harmful response without suppressing protective immunity generally. Evidence must therefore include preserved responses to unrelated challenge alongside reduced disease activity. Agonist agents also depend heavily on clustering and format, so activity cannot be assumed from binding alone.

Question 7

How is immune-related toxicity assessed preclinically?

Accepted Answer

Inflammatory effects appear across skin, gut, liver, lung and endocrine organs, and animal models underestimate them. Include histopathology across a broad organ panel, autoantibody measurement and cytokine profiling rather than body weight alone. For combinations, toxicity frequently rises more than efficacy, so both must be reported together.

Biotechnology

Biotechnology

Research Frontiers in Immune Checkpoint Modulation