Client Challenge

During the peak of the COVID-19 pandemic, one of our large biorepository client engaged KamTek to address a critical need: converting over 1,000 individual vials of human convalescent plasma from recovered COVID-19 patients into serum for research and therapeutic development. The primary challenge was to develop and validate a defibrination process that preserved COVID-19 antibody titers, while enabling large-scale processing, aliquoting, and compliant shipment to client’s facility.

The project required

• Developing a reproducible defibrination protocol that ensured no loss of antibody titers.
• Optimizing process parameters to maximize serum yield while minimizing sample loss.
• Validating the process on COVID-19 plasma before scaling to bulk operations.
• Aliquoting and preparing final samples for shipment at ultra-low temperatures (-80°C) with proper chain-of-custody documentation.

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KamTek's Approach

1. Pilot Process Development

KamTek first performed a series of controlled experiments using healthy human plasma to determine the optimal Thrombin/CaCl₂ concentrations, incubation conditions, and centrifugation parameters. This was performed to ensure that the process works before working on the precious patient samples.

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Key Findings:

1. 1 unit thrombin per mL plasma in 1M CaCl₂ produced rapid fibrin clotting within 5 minutes.
2. Kaolin was eliminated from the protocol after tests showed incomplete removal during centrifugation and potential antibody titer reduction.
3. Incubation at room temperature could be reduced to 30 minutes, improving efficiency.

2. Validation with COVID-19 Plasma

Before bulk processing, KamTek tested the optimized method on a single vial of convalescent plasma received from the client. Pre- and post-defibrination antibody titers were determined using ELISA and compared, confirming no adverse effect on COVID-19 antibody levels.

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3. Large-Scale Processing (Summary)

KamTek processed 1,001 plasma samples in four batches

Each batch was:

• Thawed at 4°C overnight to prevent thermal shock.
• Pooled and mixed in sterile 2L beakers for uniformity.
• Defibrinated using thrombin/CaCl₂, added dropwise while stirring.
• Centrifuged at 4,300 rpm for 30 minutes and filtered through 0.45µm and 0.22µm filters.

Total Serum Recovered: ~ 2.6 liters (combined yield from all four batches) from 2.75liters of plasma.

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4. Antibody Titer Verification

COVID-19 antibody titers were retested for each processed batch by ELISA test. Results confirmed no significant difference between pre-and post-defibrination samples, validating the process integrity.

5. Aliquoting & Shipment

Pooled serum was aliquoted into 1,000 labelled cryovials (250 µL each) using a repeater pipettor and the remaining serum was divided into 51 bulk tubes (45 mL each). All aliquots were stored at -80°C and shipped to client on dry ice, with full chain-of-custody and temperature compliance.

Key Highlights

• 🔬 Validated defibrination process that preserved COVID-19 antibody titers
• 🧪 Processed 1,001 convalescent plasma samples into serum in four controlled sets
• 📈 Recovered >2.6 liters of high-quality serum with minimal sample loss
• 📦 Aliquoted into 1,000 cryovials (250 µL) and 51 bulk tubes (45 mL)
• 🚚 Shipped under -80°C conditions on dry ice with full traceability

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Impact

KamTek successfully delivered a validated, scalable, and compliant solution for Client critical COVID-19 serum project. The processed samples, with preserved antibody activity, provided a valuable resource for research and therapeutic development during the pandemic.

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