Why MSC labs are switching from FBS to hPL

The shift is not a trend — it is a regulatory and scientific consequence. EMA and FDA expect a clear justification for animal-derived raw materials in clinical ATMP manufacturing. FBS creates three problems:

• Xenogeneic components — bovine proteins can trigger immunological reactions in cell therapy recipients
• Chargenvariabilität — every FBS lot behaves differently, requiring time-consuming screening programs
• Regulatory pressure — ATMP submissions using FBS require extensive risk assessments and justifications

hPL resolves all three: human origin, defined manufacturing process, and multi-year batch reservation possible.

hPL vs. FBS vs. Human Serum — key differences

What concentration of hPL is right for MSC culture?

The most common practical question — and the answer surprises many first-time users: less is usually more.

Standard FBS concentrations are around 10 %. With hPL, 5 % or less is typically sufficient, because growth factor content is substantially higher. A direct 1:1 replacement of FBS with hPL frequently leads to overstimulated growth, altered cell morphology, and potentially compromised quality attributes.

The fibrinogen problem: why hPL gels in culture — and how to solve it

This is the most discussed technical issue with hPL — and one that is under-explained in many product datasheets.

Platelet concentrates contain fibrinogen. In calcium-containing medium, fibrinogen can polymerize into fibrin — the result is a gel-like medium that clogs culture vessels and compromises results.

Solution 1: Heparin — with a critical limitation

The classic approach is adding heparin (typically 2 IU/ml). Heparin effectively inhibits fibrin polymerization. The problem: standard heparin is of porcine origin — making the overall process no longer xeno-free. For ATMP programs that require a fully xeno-free process, this is a compliance issue that needs to be addressed explicitly.

Solution 2: Fibrinogen-depleted hPL

Fibrinogen-depleted hPL removes fibrinogen from the preparation before or after lysis. The result: no gelation risk, no heparin additive required, and the xeno-free status is fully maintained. For clinical programs and ATMP submissions, this is the better choice.

GMP compliance: what hPL must provide for clinical use

For MSC manufacturing in a clinical context (Phase I–III, ATMP), the following requirements are relevant:

• ISO 13485 certified manufacturer
• EU GMP compliant manufacturing or documented risk assessment
• Fertig batch documentation: CoA, SDS, donor anamnesis, screening results (HIV, HBV, HCV, syphilis)
• Viral inactivation (solvent/detergent or S/D process) for GMP clinical grade
• Donor traceability for ATMP dossiers
• Certified European donor centers — no outsourcing to non-EU countries

The hPL supplied by SeamlessBio is manufactured by a certified European specialist — exclusively focused on hPL, with GMP infrastructure and an established supply chain for ATMP programs.

Batch reservation: why this is critical with hPL

MSC manufacturing for clinical trials runs over months to years. During this time, culture media cannot be changed without jeopardizing validation. Batch consistency is critical for regulatory continuity.

What SeamlessBio provides:

• Batch reservation from 6 weeks, significantly longer on request
• Free storage of reserved lots for up to 2 years
• Delivery across the EU and UK
• Extended traceability documentation available for Phase I–III dossiers on request

Current search questions — answered directly

“Is hPL or human serum better for MSC expansion?”

hPL for maximum proliferation rate and population doublings — especially when xeno-free status is required. Human serum as an alternative when simpler documentation is preferred and proliferation speed is less critical for the program.

“Can hPL replace FBS 1:1?”

Not recommended. Concentration optimization is necessary — typically 5 % hPL vs. 10 % FBS, but this must be validated cell-line specifically. A parallel comparison run is essential before process lock.

“Is hPL suitable for iPSC or HEK293 culture?”

hPL is primarily optimized for MSC. For HEK293 and iPSC, there are more specific serum-free alternatives. Contact us for the right supplement for your cell line and application.

“Is there hPL without heparin?”

Yes — fibrinogen-depleted hPL. No heparin additive necessary, xeno-free status fully maintained. Available from SeamlessBio on request, with full documentation for GMP use.

“What is the shelf life of hPL after thawing?”

Typically 7–14 days at +4 °C (manufacturer-specific). Aliquoting immediately after the first thaw extends working stability. Stored frozen at −20 °C, stable over the stated shelf life.