Most programs assemble their donor panel by accident. Material was ordered when it was needed, donors were whoever was available, and the panel is a description of purchasing history rather than a designed resource. A panel built deliberately does work that an accumulated one cannot, and the difference is mostly decisions made at the start.
What a panel is for
Three things, and they pull in slightly different directions. Holding donor constant so another variable can be examined cleanly. Spanning a defined range so a result can be claimed to generalise. And remaining available long enough that later work stays comparable with earlier work.
A panel optimised only for the first is small and vulnerable. One optimised only for the second is broad and expensive. The third is the one most often forgotten and the one that determines whether the panel is still useful in year two.
Deciding what defines it
| Attribute | Include when |
|---|---|
| HLA class I | CD8 responses, epitope work, NK studies where class I is the ligand |
| HLA class II | CD4 responses, helper function, antibody-related endpoints |
| KIR genotype | Any NK-directed work, where it frequently outranks HLA in explanatory power |
| Cytomegalovirus status | Anything involving memory compartments, which is most immunology |
| Age and sex | Both shape immune composition independently of anything else |
| Disease state | Where the question is about disease rather than about a healthy baseline |
The temptation is to specify everything, which narrows the eligible pool to the point where the panel cannot be assembled or replaced. Distinguishing genuine constraints from inherited preferences is the useful discipline, and it is worth revisiting periodically since criteria tend to accumulate.
Related product
Leukopak formats. Single-donor starting material, fresh or cryopreserved, with full donor documentation.
Coverage, and how much is enough
For work intended to generalise, a panel should span common alleles for population relevance and include some less common ones to test whether a finding is broadly restricted. For work holding HLA constant, the panel is narrower by design and the coverage question does not apply.
What matters more than absolute size is that the composition is deliberate and documented, so that a claim about generalisability can point at something. A panel of eight donors chosen for coverage supports a stronger statement than twenty accumulated by availability.
Making it durable
A panel that cannot be replenished is a depleting asset. Two mechanisms protect it: banking sufficient material up front, which is bounded by what was bought, and donor recall, which is bounded by donor eligibility and availability.
Both are worth having. Banking covers the near term and removes scheduling risk. Recall covers the years, and it requires the supplier to own collection, track donor identity across orders, and hold consent covering repeat collection, as set out in recallable donors.
Operating it
Record donor identifiers against every result rather than in procurement files, since a panel is only useful if the data can be traced back to it. Report per donor rather than averaging, because the spread is the output. Keep a reserved aliquot of each donor for later comparability work. And revisit the panel composition periodically, since a criterion that mattered at the start may not be the one constraining the current question.
OrganaBio documents high-resolution NGS HLA genotyping across HLA-A, HLA-B, HLA-C, HLA-DR, HLA-DQ and HLA-DP with KIR genotyping at donor program level, with selection by genotype subject to availability and repeat collection for eligible donors, across leukopaks, PBMCs and isolated T and NK populations. Specification detail is in HLA-matched material.
Frequently asked questions
What is an HLA-defined donor panel for?
Holding donor constant so another variable can be examined cleanly, spanning a defined range so results can be claimed to generalise, and remaining available long enough that later work stays comparable with earlier work.
Which attributes should define a panel?
HLA class I for CD8 and NK work, class II for CD4 and antibody-related endpoints, KIR genotype for anything NK-directed, cytomegalovirus status for memory compartment work, age and sex, and disease state where relevant. Specifying everything narrows the pool until the panel cannot be assembled.
How many donors does a panel need?
Composition matters more than size. Eight donors chosen deliberately for coverage support a stronger generalisability claim than twenty accumulated by availability, because the claim can point at a documented rationale.
Why does KIR genotype belong in an NK panel definition?
Because it frequently explains more of the variance in NK function than HLA alone. Donor and target genotype are read together, so a panel defined only by HLA leaves the dominant variable unspecified.
How do I keep a panel usable over several years?
Banking sufficient material up front covers the near term but is bounded by what was purchased. Donor recall covers the longer term and requires a supplier who owns collection, tracks donor identity across orders and holds consent for repeat collection.
Should panel results be averaged?
No. Report per donor. The spread across a deliberately composed panel is the output, and averaging removes the information the panel was built to produce.
How often should panel composition be revisited?
Periodically, because selection criteria accumulate. A constraint inherited from an earlier protocol may be narrowing the eligible pool without serving the current question.
Talk to OrganaBio
Working through this on a live program?
The scientific team works through sourcing and specification questions with cell therapy and research groups directly, including donor characterization, format selection and documentation scope.
