Chapter 1
Regenerative medicine tries to restore function in tissue that disease, injury or age has damaged. It does this by replacing lost cells, by supporting the body's own repair, or by modulating the immune response that surrounds a lesion. The work spans cell biology, materials science, pharmacology and clinical research. Each field has its own vocabulary and its own way of recording an experiment. WIA-BIO-020 (version 1.0.0, category BIO / Biotechnology) gives these threads a shared structure. It covers stem cell therapies, tissue regeneration, organ repair and growth factor delivery, and it defines how a cell preparation, a signalling molecule, a scaffold and a clinical application are described so that others can check the description.
The standard carries the motto 홍익인간 (弘益人間), "benefit all humanity". In practice it is a scientific foundation for technologies that restore, replace and regenerate damaged tissues and organs. Six themes organise the specification: stem cell classification and protocols, tissue engineering, organ repair strategies (cardiac, neural, musculoskeletal), growth factor delivery, scaffold engineering, and clinical protocols aligned with the FDA RMAT designation and the EMA ATMP framework.
Four stem cell classes anchor the vocabulary. They differ in origin and in how much developmental potential they retain, and that difference drives how each is used and how its risks are managed.
| Type | Full name | Source | Potency | Typical application |
|---|---|---|---|---|
| ESC | Embryonic stem cell | Inner cell mass of the blastocyst | Pluripotent | All tissue types; disease modelling, drug screening |
| iPSC | Induced pluripotent stem cell | Reprogrammed somatic cells | Pluripotent | Patient-specific therapy |
| MSC | Mesenchymal stem cell | Bone marrow, adipose, umbilical cord, dental pulp | Multipotent | Bone, cartilage, muscle |
| HSC | Hematopoietic stem cell | Bone marrow, peripheral blood, cord blood | Multipotent | Blood and immune cells |
Pluripotent cells can become any cell type. Embryonic cells express OCT4, SOX2 and NANOG, are telomerase positive and so divide without a built-in limit, and raise ethical questions that keep their therapeutic use dependent on approval. iPSCs avoid that objection because they come from the patient's own fibroblasts or blood cells. They are made by forcing the four Yamanaka factors (OCT4, SOX2, KLF4 and c-MYC) into the cell. Reprogramming efficiency is expressed as η = (N_iPSC / N_initial) × 100%, and the specification gives a typical range of 0.01% to 3% depending on method. Multipotent cells are narrower. MSCs form bone, fat, cartilage and, to a limited degree, muscle and neural cells. HSCs give rise to the myeloid lineage (red cells, platelets, granulocytes, monocytes) and the lymphoid lineage (T, B and NK cells).
A regenerative product is more than a vial of cells. It is cells, plus the factors that tell them what to do, plus often a physical carrier, plus a documented clinical intent. The data format follows that decomposition and gives each part its own record, so the parts can be validated separately and linked.
The stem-cell record groups preparations by source class (ESC, MSC, HSC, neural stem cell, iPSC). It carries a pseudonymous cell-record identifier bound to the donor's consent, and donor metadata (age, sex, lot number, and ethnicity where consented). It also holds passage number, viability at thaw, sterility status, karyotype and a marker panel. Sterility means mycoplasma-free per USP <63> and endotoxin per USP <85> below 0.5 EU/mL. For clinical-grade preparations G-band karyotyping is required. A chain-of-custody hash ties the cells to the signing key of the contributing institution.
The marker panel is the point where identity is made checkable. The ISCT 2006 definition of an MSC requires plastic adherence, tri-lineage differentiation (osteogenic, adipogenic, chondrogenic), and a specific surface profile:
The envelope extends the negative panel with CD11b and CD79a. iPSC quality control adds a normal karyotype of 46 chromosomes, pluripotency marker expression above 90%, a teratoma formation assay, demonstrated potential toward all three germ layers, and verification of epigenetic reprogramming.
The growth-factor descriptor identifies the factor (BMP-2, BMP-7, TGF-beta, VEGF, PDGF, FGF-2, IGF-1, NGF, GDNF, EGF, HGF, SDF-1) and its source. The source may be recombinant (E. coli, yeast or mammalian cells), native from platelet-rich plasma, or cell-free conditioned medium. It also records purity by HPLC, biological activity from a standard assay, the formulation (lyophilised or liquid, with or without carrier protein) and the storage profile, typically -20 °C to -80 °C with documented stability. Reference dosing in the specification varies by factor and target cell:
| Factor | Function | Target cells | Optimal dose |
|---|---|---|---|
| VEGF | Angiogenesis | Endothelial cells | 10–50 ng/ml |
| BMP-2 | Bone formation | Osteoblasts | 50–200 ng/ml |
| TGF-β | ECM production | Fibroblasts | 1–10 ng/ml |
| BDNF | Neurogenesis | Neurons | 10–100 ng/ml |
The scaffold-and-delivery descriptor names the scaffold material (cross-referencing the WIA-BIO-006 tissue-engineering catalogue) and the delivery vehicle: injectable hydrogel, in-situ-forming gel, pre-formed scaffold, microsphere-encapsulated or cell-laden bioink. It also carries the cell density, with 1e6 to 1e8 cells/mL typical for therapeutic injection, and the release profile established in the operator's pharmacokinetic study. These formulation choices matter because delivery shapes the pharmacology. A bolus injection acts immediately but follows C(t) = C₀ × e^(-kt), with half-lives of 2–24 hours for most growth factors. Scaffold release follows M_released(t) = M_total × (1 - e^(-kt)) and can be tuned from immediate to sustained to programmed patterns. Microspheres (1–200 μm) release by diffusion, polymer degradation or osmotic pressure, with an encapsulation efficiency target above 70%. Gene delivery uses adenovirus (high efficiency, transient), lentivirus (stable integration) or AAV (long-term expression), or non-viral plasmid DNA, mRNA and lipid nanoparticles. Combination therapy is judged by synergy, Effect_combined > Effect_A + Effect_B. Examples include VEGF with FGF-2 for angiogenesis and NGF with BDNF for neural regeneration.
Three quantities let results from different laboratories be compared:
R = (ΔT / Δt) × E Regeneration rate (cells/day)
S = (N_viable / N_total) × 100% Cell survival
I = (V_integrated / V_total) × F_vascular × F_mechanical Integration score, 0-1The integration score is the most instructive. A graft can occupy most of the defect yet fail clinically if it is not perfused or cannot bear load, so volumetric engraftment is multiplied by vascular and mechanical factors. A poorly vascularised graft therefore scores low even at high fill. Survival is simple arithmetic: 8,500,000 viable iPSCs out of 10,000,000 gives S = 85%. The standard asks for the conditions, such as hypoxic culture, to be recorded with it. The regeneration formula divides a change in tissue volume by time, yet the SDK reports the rate in cells/day, so implementers should state their units explicitly.
The API surface mirrors these calculations as typed requests and responses. For regeneration the request names the tissue (cardiac, neural, bone, cartilage or skin), the cell density, the time frame in days and the growth factors used:
interface RegenerationRequest {
tissueType: 'cardiac' | 'neural' | 'bone' | 'cartilage' | 'skin';
cellDensity: number; // cells/ml
timeFrame: number; // days
growthFactors: string[];
}
interface RegenerationResponse {
rate: number; // cells/day
recoveryPercentage: number;
timeToComplete: number; // days
feasibility: 'high' | 'medium' | 'low';
}The survival call returns a survivalRate from 0 to 100, a qualitative viability grade (excellent, good, fair or poor) and a list of recommendations. The scaffold call takes a tissue type, material, porosity between 0 and 1, size in cm³ and optional mechanical requirements such as Young's modulus. It returns dimensions, pore size in μm, degradation time in months, predicted mechanical properties and a biocompatibility grade. The CLI wraps the same functions, for example wia-bio-020 calc-regen --tissue cardiac --cells 1e8 --days 14.
The specification offers no market sizing, and none is invented here. What it does show is that adoption in this field follows regulatory acceptance more than technical novelty. The clinical-application descriptor records the regional trial registrations (ClinicalTrials.gov, EU CTIS, KR CRIS, WHO ICTRP) and the trial stage, and the compliance target is explicitly the FDA RMAT and EMA ATMP pathways. A developer, hospital or contract manufacturer that can hand over records in a common structure gains the most where review is documentation-heavy. Allogeneic and autologous strategies differ commercially. An autologous iPSC product is made per patient, while an allogeneic one must manage HLA compatibility across many recipients. The record format carries the donor and lot metadata that either model needs.
The use cases in the specification each pair a cell type with a tissue problem and a delivery strategy:
The same record structure serves all six. Only the indication, the tissue-specific cell density and the scaffold change. Indications are coded with WHO ICD-11 and SNOMED-CT, and each application declares its intended effect: replace lost tissue, promote endogenous regeneration, or immunomodulate. The last is the main route for MSCs, which secrete IL-10, TGF-β and PGE2, suppress T-cell proliferation, shift macrophages from M1 to M2, and show low immunogenicity.
The standard does not replace the regulators. It aligns with them, citing ISCT 2006 for MSC identity, USP methods for sterility and endotoxin, FDA/ISO 10993 for scaffold biocompatibility, and ISO Class 5 for sterile culture conditions. Product claims depend on external review, and the specification makes the evidence trail machine-readable. A separate generic layer for signing and conformance tiers exists across the WIA family, but it adds nothing field-specific.
The specification names six safety considerations, and each maps to a failure mode peculiar to cell therapy:
The quality-test envelope turns these into release criteria for a batch. It covers identity (STR profiling for human cells, immunophenotyping against the marker panel), purity (residual host protein, DNA, serum and antibiotics) and potency, alongside the sterility, endotoxin and karyotype fields in the cell record. Adverse events and audit trails have their own interface in Phase 2, so a safety signal in a patient can be traced to the lot and donor that produced the cells.
A compliant system must contain six components: cell source management (origin, passage, characterisation), validated differentiation protocols, real-time quality control, a growth factor calculator for dose and timing, a scaffold designer for material, porosity and mechanics, and a clinical tracker for outcomes and safety. These are working modules that a manufacturing site would build or buy. The first and the last matter most for traceability, because the cell record opens the chain and the clinical tracker closes it.
The standard also integrates with neighbouring WIA specifications. WIA-INTENT supports intent-based therapy selection. WIA-OMNI-API serves as a biomedical API gateway. WIA-HEALTH covers patient monitoring. WIA-BIO-002 covers cell culture technology, and WIA-BIO-006 supplies the scaffold material catalogue. Donor consent is tied to the WIA-A11Y attestation chain. A TypeScript SDK (@wia/bio-020) and the CLI are the reference implementations, and the NPM package exposes an SDK class with calculateRegenerationRate for tissue types such as neural, where the growth factors might be BDNF, NGF and NT-3.
Version 1.0.0 fixes the descriptors and the three core metrics. It leaves scientific questions open that the format should absorb without breaking. Reprogramming methods are still improving, and the efficiency range of 0.01% to 3% reflects how much the method matters. Gene-delivery and lipid-nanoparticle approaches are evolving, and cell-free conditioned medium already appears as a growth-factor source, which suggests that products built on secreted factors rather than living cells will need the same descriptors. Combination therapies are expected to benefit from recording synergy effects, and organ-level repair beyond the three listed targets will test whether the integration score stays adequate. Beyond that, the specification does not forecast outcomes.
This chapter set out the problem WIA-BIO-020 addresses: regenerative products depend on cells, signalling factors, carriers and clinical intent that are usually documented separately. The standard names the four stem cell classes and the marker panels that distinguish them. It records cells, growth factors, scaffolds, clinical applications and quality tests as linked descriptors. It condenses performance into survival, regeneration and integration metrics, and ties safety to concrete risks such as tumorigenicity, contamination and HLA mismatch. The typed API and CLI make these calculations repeatable.
The next chapter turns from the overview to the cells themselves. It examines the stem cell record in detail, from donor consent and passage tracking to karyotype and marker panels, and shows how culture conditions and reprogramming methods determine whether a preparation reaches clinical grade.