Resolve the variables that drive productivity, viability and process robustness.
Use literature and vendor information to define screening priors, never to imply cell-line-specific predictive accuracy. Manufacturing use requires authorized development and plant evidence.
Cells and product
Track viable and total cell concentration, growth and death, integral viable-cell density, specific productivity, product formation and degradation, cell lysis and the quality proxies required by the context of use. Parameterize temperature shifts, feed phases and productivity changes independently where data supports them.
Substrates and metabolites
Represent glucose, glutamine or alternative nitrogen sources, amino-acid or aggregate nutrient groups, lactate, ammonium, dissolved oxygen and carbon dioxide, osmolality and pH-related additions. Add inhibition, overflow metabolism, lactate consumption or maintenance only when the data can identify those mechanisms.
Scale and facility coupling
Couple OUR to OTR, gas flow and oxygen enrichment; link feeds to working volume, mixing and local exposure; reconcile heat and cooling; then pass harvest titer, volume, solids and impurities into clarification, capture, viral safety, polishing, UF/DF, formulation, filling and finite-capacity scheduling.
Model layerMinimum inputsReview outputs
KineticsBatch-aligned cell, product, substrate, metabolite and event dataTrajectories, residuals, uncertainty and parameter identifiability
Mass transferGeometry, working volume, kLa basis, gas policy, OUR and broth propertiesOTR margin, gas demand, limiting period and extrapolation risk
Harvest + DSPVolume, titer, solids, impurity assays, step capacities and yieldsCycles, pool sizes, consumables, yield, queue and hold-time compliance
EconomicsMedia and feed costs, single-use demand, utilities, labor and equipment basisCOGS interval, annual output, dominant drivers and break-even targets
Do not report only final titerExport all time points, state variables, feeds, events, mass residuals, boundaries, uncertainty intervals and sensitivity runs.
Do not hide maturityLabel the model screening, calibrated, validated or not decision-ready for the named decision and operating envelope.