이 연구는 미국 국립과학재단(National Science Foundation for Distinguished Young Scholars, 82125018)의 재정 지원을 받았습니다.

인간 탯줄은 베이징 칭화 창겅 병원에서 입수했습니다. 인간 탯줄 중간엽 줄기세포(UCMSC)의 획득, 분리 및 배양에 관한 모든 절차와 프로토콜은 정보에 입각한 동의와 베이징 칭화창겅 병원 윤리 위원회(출원 번호 22035-4-02)의 승인을 받아 수행되었으며, 절차와 프로토콜은 1964년 헬싱키 선언 및 이후 개정안 또는 이에 상응하는 윤리 기준을 준수했습니다.
1. hMSC, HEK293T 세포...

용해 가능한 마이크로캐리어를 기반으로 한 부착 세포의 폐쇄 시스템 생산

<ol>
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면역 요법과 줄기 세포 요법 모두 살아있는 세포를 약물로 사용합니다. 그러나 최종 제품은 저분자 또는 바이러스와 같은 방식으로 정제하거나 멸균해서는 안 됩니다. 그러므로, QbD(Quality by Design)의 원칙은 항상 염두에 두어야 하며, 셀 생산 중 화학 제조 및 제어(CMC) 공정에 실질적으로 적용되어야 한다23. 완전 폐쇄형 세포 배양 시스템, 처리 시스템 및 충전 시스템은 요구 사항?...

CGT 산업은 지난 20년 동안 기하급수적으로 확장되었습니다. 차세대 의약품의 발전은 수많은 난치성 질환을 치료하고 완치할 것으로 예상됩니다1. 2017년 미국 식품의약국(FDA)이 CGT 제품인 킴리아(Kymriah)를 최초로 승인한 이후, 전 세계적으로 CGT 관련 연구 개발은 빠른 속도로 계속 성장하고 있으며, FDA는 CGT에 대한 활발한 임상시험용 신약 신청이 2018년에 500건으로 증가했다고 밝혔다2. 2030년까지 미국에서 CGT 제품의 승인 건수는 54-74건이 될 것으로 예측되었다2.
CGT 연구 및 혁신의 급속한 성장은 흥미진진하지만, 저렴한 비용으로 필요한 만큼 많은 환자에게 도달할 수 있는 유망한 의약품을 제공할 수 있는 실험실 연구와 산업 규모 제조 사이에는 여전히 큰 기술 격차가 있습니다. 이러한 임상시험에 채택된 현재 공정은 소규모 실험을 위해 실험실에서 확립되었으며, CGT 제조를 개선하고 혁신하기 위해서는 상당한 노력이 필요하다3. CGT 제품에는 여러 유형이 있으며, 대부분은 동종 세포, 자가 세포, 엔지니어링 또는 천연 세포를 기반으로 합니다. 이러한 살아있는 약물은 저분자 개체나 생물학적 제제보다 훨씬 더 복잡하기 때문에 대규모 제조는 중요한 과제입니다 4,5,6. 이 연구에서는 CGT에 널리 적용되는 3개의 앵커리지 의존성 세포에 대한 대규모 세포 생산 프로토콜을 시연합니다. 여기에는 세포 기반 치료에 사용되어 온 인간 중간엽 줄기/기질 세포(hMSC)와 최종 치료 세포 산물의 유전 공학을 위한 바이러스 생산에 사용되는 HEK293T 세포 및 Vero 세포가 포함됩니다. 앵커리지 의존성 세포는 일반적으로 수동 처리가 필요한 평면 시스템에서 배양됩니다. 그러나 수동 배양 방법은 상당한 노동력이 필요하고 오염되기 쉬워 최종 제품의 품질을 저하시킬 수 있습니다. 또한 인라인 공정 제어가 없어 배치 간에 상당한 품질 변동이 발생합니다7. 줄기세포 치료제를 예로 들면, 200개 이상의 줄기세포 치료제 후보 물질로 구성된 유망한 파이프라인을 통해 임상 응용 분야의 수요를 충족하려면 연간 300조 개의 hMSC가 필요할 것으로 추정됩니다8. 따라서, 치료용 세포의 대규모 제조는 이러한 높은 세포 요구량으로 이러한 치료적 개입을 수행하기 위한 전제조건이 되었다9.
평면 시스템의 차질을 배제하기 위해, 종래의 비용해성 마이크로캐리어(10,11,12,13)를 사용하여 교반 탱크 바이오리액터에서 대규모 제조 공정을 개발하기 위한 노력이 이루어졌지만, 이들은 복잡한 준비 절차와 낮은 세포 수확 효율 14로 어려움을 겪고 있다 . 최근에, 우리는 줄기세포 확장을 위한 용해성 마이크로캐리어를 혁신하였는데, 이는 종래의 비용해성 상용 마이크로캐리어(15)로부터의 세포 수확의 문제를 회피하는 것을 목표로 한다. 이 새로운 상용 GMP 등급 3D 용해성 다공성 마이크로 캐리어인 3D TableTrix는 대규모 셀 생산에 대한 큰 잠재력을 보여주었습니다. 실제로, 이러한 다공성 마이크로캐리어를 기반으로 한 3D 배양은 세포 부착, 증식, 이동 및 활성화를 촉진하기 위해 유리한 생체 모방 미세환경을 잠재적으로 재현할 수 있습니다16. 마이크로캐리어의 다공성 구조 및 상호 연결된 공극 네트워크는 더 큰 세포 접착 영역을 생성하고 산소, 영양소 및 대사 산물의 교환을 촉진하여 시험관 내 세포 확장을 위한 최적의 기질을 생성할 수 있다17. 이러한 GMP 등급 3D 용해성 다공성 마이크로캐리어의 높은 다공성은 hMSC의 대규모 팽창을 가능하게 하고, 세포가 완전히 용해될 수 있는 능력은 이러한 팽창된 세포의 효율적인 수확을 가능하게 한다18. 또한 GMP 등급 제품이며 중국 약물 평가 센터(출원 번호: F20210000003 및 F20200000496)19 및 미국 FDA(FDA, USA; 약물 마스터 파일 번호: 35481)20.
여기에서, 우리는 hMSC, HEK293T 셀 및 Vero 셀 증식을 위해 이들 분산성 및 용해성 다공성 마이크로캐리어를 사용하는 자동화된 폐쇄형 산업 규모 셀 생산(ACISCP) 시스템(18)을 예시한다. 당사는 5L 바이오리액터에서 15L 바이오리액터로 hMSC의 2단계 확장(9일 동안 누적 128배 팽창)을 성공적으로 달성했으며, 최종적으로 단일 생산 배치에서 최대 1.1 x 1010 hMSC를 얻었습니다. 세포는 마이크로캐리어를 완전히 용해시켜 수거하고, 농축하고, 세척하고, 연속흐름 원심분리기 기반 세포 처리 시스템으로 제형화한 후, 세포 충전 시스템으로 분주하였다. 또한 hMSC 제품의 품질을 평가하여 규정 준수를 확인했습니다. 또한 CGT 산업에서 광범위하게 적용되는 두 가지 다른 유형의 앵커리지 셀인 HEK293T 셀과 Vero 셀의 스케일 업 생산을 위한 이러한 용해성 마이크로캐리어의 적용을 시연했습니다. HEK293T 세포의 피크 세포 밀도는 1.68 x 10 7 cells/mL에 도달한 반면, Vero 세포의 피크 밀도는 1.08 x 107 cells/mL에 도달했습니다. ACISCP 시스템은 다양한 부착 세포를 배양하는 데 적용할 수 있으며, CGT의 산업화를 가속화하는 데 기여하는 강력한 플랫폼이 될 수 있습니다.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr >
			<td >0.25% trypsin EDTA</td>
			<td >BasalMedia</td>
			<td >S310JV</td>
			<td >Used for 2D cell harvest.</td>
		</tr>
		<tr >
			<td >3D FloTrix Digest</td>
			<td >CytoNiche Biotech</td>
			<td >R001-500</td>
			<td >This is a reagent that specifically dissolves 3D TableTrix microcarriers.</td>
		</tr>
		<tr >
			<td >3D FloTrix MSC Serum Free Medium</td>
			<td >CytoNiche Biotech</td>
			<td >RMZ112</td>
			<td >This is a serum-free,animal-free medium for mesenchymal stem cell expansion and maintenance in 2D planar culture as well as 3D culture on 3D TableTrix microcarriers.</td>
		</tr>
		<tr >
			<td >3D FloTrix Single-Use Filtration Module</td>
			<td >CytoNiche Biotech</td>
			<td >R020-00-10</td>
			<td >This module contains 0.22 &#956;m capsule filters used for filtration of culture medium and digest solution.</td>
		</tr>
		<tr >
			<td >3D FloTrix Single-Use Storage Bag (10 L)</td>
			<td >CytoNiche Biotech</td>
			<td >R020-00-03</td>
			<td >Used as feed bag for 5 L bioreactor.</td>
		</tr>
		<tr >
			<td >3D FloTrix Single-Use Storage Bag (3 L)</td>
			<td >CytoNiche Biotech</td>
			<td >R020-00-01</td>
			<td >Used as cell seeding or transfer bags.</td>
		</tr>
		<tr >
			<td >3D FloTrix Single-Use Storage Bag (50 L)</td>
			<td >CytoNiche Biotech</td>
			<td >R020-00-04</td>
			<td >Used as feed bag for 15 L bioreactor.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaPACK Disposable Fill&#38;Finish Consumable Kit</td>
			<td >CytoNiche Biotech</td>
			<td >PACK-01-01</td>
			<td >This is a standard kit adapted to 3D vivaPACK fill and finish system.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaPACK fill and finish system for cells</td>
			<td >CytoNiche Biotech</td>
			<td >vivaPACK</td>
			<td >This system is a closed liquid handling device, with automated mixing and gas exhausting functions. Cells resuspended in cryopreservation buffer can be rapidly and evenly aliquoted into 20 bags per batch.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaPREP PLUS cell processing system</td>
			<td >CytoNiche Biotech</td>
			<td >vivaPREP PLUS</td>
			<td >This system is a continuous flow centrifuge-based device.Cells can be concentrated, washed, and resuspended under completely closed procedures.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaPREP PLUS Disposable Cell Processing Kit</td>
			<td >CytoNiche Biotech</td>
			<td >PREP-PLUS-00</td>
			<td >This is a standard kit adapted to 3D vivaPREP PLUS cell processing.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaSPIN&#160; bioreactor 15 L</td>
			<td >CytoNiche Biotech</td>
			<td >FTVS15</td>
			<td >This bioreactor product employs a controller, a 15 L glass stirred-tank vessel, and assessories. A special perfusion tube is available.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaSPIN&#160; bioreactor 5 L</td>
			<td >CytoNiche Biotech</td>
			<td >FTVS05</td>
			<td >This bioreactor product employs a controller, a 5 L glass stirred-tank vessel, and assessories.A special perfusion tube is available.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaSPIN Closed System Consumable Pack (10/15 L)</td>
			<td >CytoNiche Biotech</td>
			<td >R020-10-10</td>
			<td >This is a standard tubing kit adapted to 3D vivaSPIN bioreactor 15 L, containing sampling bags.</td>
		</tr>
		<tr >
			<td >3D FloTrix vivaSPIN Closed System Consumable Pack (2/5 L)</td>
			<td >CytoNiche Biotech</td>
			<td >R020-05-10</td>
			<td >This is a standard tubing kit adapted to 3D vivaSPIN bioreactor 5 L, containing sampling bags.</td>
		</tr>
		<tr >
			<td >3D TableTrix microcarriers G02</td>
			<td >CytoNiche Biotech</td>
			<td >G02-10-10g</td>
			<td >These porous and degradable microcarriers are suitable for HEK293T cell culture. They come pre-sterilized in 10g/bottle with C-Flex tubings for welding to tubes on bioreactors.</td>
		</tr>
		<tr >
			<td >3D TableTrix microcarriers V01</td>
			<td >CytoNiche Biotech</td>
			<td >V01-100-10g</td>
			<td >These porous and degradable microcarriers are suitable for adherent cell culture, they come as non-sterilized microcarriers that need to be autoclaved in PBS before use. They are especially suitable for vaccine production.</td>
		</tr>
		<tr >
			<td >3D TableTrix microcarriers W01</td>
			<td >CytoNiche Biotech</td>
			<td >W01-10-10g (single-use packaging); 
			W01-200 (tablets)</td>
			<td >These porous and degradable microcarriers are suitable for adherent cell culture, especially for cells that need to be harvested as end products. They come pre-sterilized in 10g/bottle with C-Flex tubings for welding to tubes on bioreactors.The product has obtained 2 qualifications for pharmaceutical excipients from CDE, with the registration numbers of [F20200000496; F20210000003]. It has also received DMF qualification for pharmaceutical excipients from FDA, with the registration number of [DMF:35481]</td>
		</tr>
		<tr >
			<td >APC anti-human CD45 Antibody</td>
			<td >BioLegend</td>
			<td >368512</td>
			<td >Used in flow cytometry for MSC identity assessment</td>
		</tr>
		<tr >
			<td >Calcein-AM/PI Double Staining Kit</td>
			<td >Dojindo</td>
			<td >C542</td>
			<td >Calcein-AM/PI Double Staining Kit is utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stain viable and dead cells, respectively.</td>
		</tr>
		<tr >
			<td >Cap for EZ Top Container Closures for NALGENE-containers (500mL)</td>
			<td >Saint-Gobain</td>
			<td>CAP-38</td>
			<td >Brands and catalogue numbers are only for example, similar products are available from various suppliers and as long as they have the same functionality, items could be substituted with other brands.</td>
		</tr>
		<tr >
			<td >C-Flex Tubing, Formulation 374 (0.25 in x 0.44 in)</td>
			<td >Saint-Gobain</td>
			<td >374-250-3</td>
			<td >Used for tube welding and disconnection.</td>
		</tr>
		<tr >
			<td >CryoMACS Freezing Bag 50</td>
			<td >Miltenyi Biotec&#160;</td>
			<td >200-074-400</td>
			<td >Used for expanding the 3D FloTrix vivaPACK Disposable Fill&#38;Finish Consumable Kit.</td>
		</tr>
		<tr >
			<td >Dimethyl Sulfate (DMSO)&#160;</td>
			<td >Sigma</td>
			<td >D2650-100mL</td>
			<td >Used for preparation of cryopreservation solution.</td>
		</tr>
		<tr >
			<td >Dulbecco&#39;s Modified Eagle Medium (DMEM)</td>
			<td >BasalMedia</td>
			<td >L120KJ</td>
			<td >Used for cultivation of HEK293T and Vero cells.</td>
		</tr>
		<tr >
			<td >DURAN Original GL 45 Laboratory bottle (2 L)</td>
			<td >DWK life sciences</td>
			<td >218016357</td>
			<td >Used for waste collection from the 5 L bioreactor.</td>
		</tr>
		<tr >
			<td >DURAN Original GL 45 Laboratory bottle (5 L)</td>
			<td >DWK life sciences</td>
			<td >218017353</td>
			<td >Used for waste collection from the 15 L bioreactor.</td>
		</tr>
		<tr >
			<td >DURAN Original GL 45 Laboratory bottle (500 mL)</td>
			<td >DWK life sciences</td>
			<td >218014459</td>
			<td >Used for supplementary bottle of 0.1 M NaOH.</td>
		</tr>
		<tr >
			<td >EZ Top Container Closures for NALGENE-containers (500mL)</td>
			<td >Saint-Gobain</td>
			<td>EZ500 ML-38-2</td>
			<td >Brands and catalogue numbers are only for example, similar products are available from various suppliers and as long as they have the same functionality, items could be substituted with other brands.</td>
		</tr>
		<tr >
			<td >Fetal bovine serum (FBS) superior quality</td>
			<td >Wisent</td>
			<td >086-150</td>
			<td >Used for cultivation of HEK293T cells.</td>
		</tr>
		<tr >
			<td >FITC anti-human CD14 Antibody</td>
			<td >BioLegend</td>
			<td >301804</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >FITC anti-human CD34 Antibody</td>
			<td >BioLegend</td>
			<td >343504</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >FITC anti-human CD90 (Thy1) Antibody</td>
			<td >BioLegend</td>
			<td >328108</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >Flow cytometry</td>
			<td >Beckman Coulter</td>
			<td >CytoFLEX</td>
			<td >Used for cell identity assessment.</td>
		</tr>
		<tr >
			<td >Fluorescence Cell Analyzer</td>
			<td >Alit life science</td>
			<td >Countstar Rigel S2</td>
			<td >Used for cell counting. Cell viability can be calculated by staining with AO/PI dyes.</td>
		</tr>
		<tr >
			<td >GL 45 Multiport Connector Screw Cap with 2 ports&#160;</td>
			<td >DWK life sciences</td>
			<td >292632806</td>
			<td >Brands and catalogue numbers are only for example, similar products are available from various suppliers and as long as they have the same functionality, items could be substituted with other brands.</td>
		</tr>
		<tr >
			<td >Glucose Meter</td>
			<td >Sinocare</td>
			<td >6243578</td>
			<td >Used for detecting glucose concentration in cell culture medium and supernatant.</td>
		</tr>
		<tr >
			<td >Hank&#39;s Balanced Salt Solution (HBSS), with calcium and magnesium</td>
			<td >Gibco</td>
			<td >14025092</td>
			<td >Used for preparation of digest solution.</td>
		</tr>
		<tr >
			<td >Human Albumin 20% Behring (HSA)</td>
			<td >CSL Behring</td>
			<td >N/A</td>
			<td >Used for preparation of wash buffer.</td>
		</tr>
		<tr >
			<td >Inverted fluorescent microscope</td>
			<td >OLYMBUS</td>
			<td >CKX53SF</td>
			<td >Used for brifgt field and fluorescent observation and imaging.</td>
		</tr>
		<tr >
			<td >Nalgene Measuring Cylinder (500 mL)</td>
			<td >Thermo Scientific</td>
			<td >3662-0500PK</td>
			<td >Used for calibrating the liquid handling volume speed of peristaltic pumps.</td>
		</tr>
		<tr >
			<td >Newborn calf serum (NBS) superfine</td>
			<td >MINHAI BIO</td>
			<td >SC101.02</td>
			<td >Used for cultivation of Vero cells.</td>
		</tr>
		<tr >
			<td >OriCell human mesenchymal stem cell adipogenic differentiation and characterization kit</td>
			<td >Cyagen</td>
			<td >HUXUC-90031</td>
			<td >Used for tri-lineage differentiation of hUCMSCs.</td>
		</tr>
		<tr >
			<td >OriCell human mesenchymal stem cell chondrogenic differentiation and characterization kit</td>
			<td >Cyagen</td>
			<td >HUXUC-90041</td>
			<td >Used for tri-lineage differentiation of hUCMSCs.</td>
		</tr>
		<tr >
			<td >OriCell human mesenchymal stem cell osteogenic differentiation and characterization kit</td>
			<td >Cyagen</td>
			<td >HUXUC-90021</td>
			<td >Used for tri-lineage differentiation of hUCMSCs.</td>
		</tr>
		<tr >
			<td >PE anti-human CD105 Antibody</td>
			<td >BioLegend</td>
			<td >800504</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >PE anti-human CD19 Antibody</td>
			<td >BioLegend</td>
			<td >302208</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >PE anti-human CD73 (Ecto-5&#39;-nucleotidase) Antibody</td>
			<td >BioLegend</td>
			<td >344004</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >PE anti-human HLA-DR Antibody</td>
			<td >BioLegend</td>
			<td >307605</td>
			<td >Used in flow cytometry for MSC identity assessment.</td>
		</tr>
		<tr >
			<td >Phosphate Buffered Saline (PBS)</td>
			<td >Wisent</td>
			<td >311-010-CL</td>
			<td >Used in autoclaving of glass vessel and V01 microcarriers, and replacement of culture medium.</td>
		</tr>
		<tr >
			<td >Sani-Tech Platinum Cured Sanitary Silicone Tubing (0.13 in x 0.25 in)</td>
			<td >Saint-Gobain</td>
			<td >ULTRA-C-125-2F</td>
			<td >Used for solution transfering driven by peristaltic pumps.</td>
		</tr>
		<tr >
			<td >Sterile Saline</td>
			<td >Hopebiol</td>
			<td >HBPP008-500</td>
			<td >Used for preparation of wash buffer.</td>
		</tr>
		<tr >
			<td >Trypzyme Recombinant Trypsin</td>
			<td >BasalMedia</td>
			<td >S342JV</td>
			<td >This reagent is used for bead-to-bead transfer of HEK293T and Vero cells.</td>
		</tr>
		<tr >
			<td >Tube Sealer</td>
			<td >Yingqi Biotech</td>
			<td >Tube Sealer I</td>
			<td >This sealer is compatible with both C-Flex tubing and PVC tubing.</td>
		</tr>
		<tr >
			<td >Tube Welder for PVC tubing</td>
			<td >Chu Biotech</td>
			<td >Tube Welder Micro I</td>
			<td >Used for welding of PVC tubing.</td>
		</tr>
		<tr >
			<td >Tube Welder for TPE tubing</td>
			<td >Yingqi Biotech</td>
			<td >Tube Welder I-V2</td>
			<td >Used for welding of TPE tubing.</td>
		</tr>
		<tr >
			<td >ViaStain AO / PI Viability Stains</td>
			<td >Nexcelom</td>
			<td >CS2-0106-25mL</td>
			<td >Dual-Fluorescence Viability, using acridine orange (AO) and propidium iodide (PI), is the recommended method for accurate viability analysis of primary cells, such as PBMCs, and stem cells in samples containing debris.</td>
		</tr>
	</tbody>
</table>

large-scale cell production based on gmp-grade dissolvable porous microcarriers

세포 및 유전자 치료(CGT) 산업의 연구자들은 세포의 효율적이고 대규모적인 확장이라는 만만치 않은 과제에 오랫동안 직면해 왔습니다. 2차원(2D) 평면 배양 시스템의 주요 단점을 해결하기 위해 인간 중간엽 줄기/기질 세포(hMSC), HEK293T 세포 및 Vero 세포를 포함한 부착 세포의 3D 배양을 위한 GMP 등급의 용해성 다공성 마이크로캐리어를 기반으로 하는 자동 폐쇄형 산업 규모 세포 생산(ACISCP) 플랫폼을 혁신적으로 개발했습니다. 대규모 확장을 달성하기 위해 5L 및 15L 교반 탱크 바이오리액터로 2단계 확장을 수행하여 9일 이내에 전체 128배 팽창으로 1.1 x 1010 hMSC를 생산했습니다. 세포는 마이크로캐리어를 완전히 용해시켜 수거하고, 농축하고, 세척하고, 연속 흐름 원심분리기 기반 세포 처리 시스템으로 제형화한 다음, 세포 충전 시스템으로 분주하였다. 2D 평면 배양과 비교했을 때, 3D 배양에서 채취한 hMSC의 품질에는 큰 차이가 없습니다. 우리는 또한 이러한 용해성 다공성 마이크로캐리어를 CGT 부문의 다른 인기 있는 세포 유형에도 적용했습니다. 구체적으로, HEK293T 세포 및 Vero 세포는 각각 1.68 x 10 7 cells/mL 및 1.08 x 107 cells/mL의 피크 세포 밀도로 배양되었습니다. 이 연구는 부착 세포의 산업 규모 제조를 달성하기 위해 GMP 등급 용해성 마이크로캐리어 및 고급 폐쇄 장비의 특성을 활용하는 바이오프로세스 엔지니어링 플랫폼을 사용하기 위한 프로토콜을 제공합니다.

The CGT industry has witnessed an exponential expansion over the past two decades. The evolution of next-generation medicines is anticipated to treat and cure numerous refractory diseases1. Since the first Food and Drug Administration (FDA) approval of a CGT product, Kymriah, in 2017, CGT-related research and development in the world has continued to grow at a fast rate, with the FDA seeing active investigational new drug applications for CGT increased to 500 in 20182. It had been predicted that the number of approvals of CGT products will likely be 54-74 in the United States by 20302.
While the rapid growth in CGT research and innovation is exciting, there is still a large technological gap between lab research and industrial-scale manufacturing that could deliver these promising medicines to reach as many patients as needed at affordable costs. The current processes adopted for these clinical trials were established in labs for small-scale experiments, and significant efforts are needed to improve and innovate on CGT manufacturing3. There are many types of CGT products, most of them based on live cells, which can be allogenic, autologous, engineered, or natural. These living drugs are much more complex than small molecular entities or biologics, hence making large-scale manufacturing a significant challenge4,5,6. In this work, we demonstrate a large-scale cell production protocol for three anchorage-dependent cells that are widely applied in CGTs. These include human mesenchymal stem/stromal cells (hMSCs), which have been used for cell-based therapy, and HEK293T cells and Vero cells, both of which are used to produce viruses for the genetic engineering of the final therapeutic cell product. Anchorage-dependent cells are commonly cultured on planar systems, which require manual processing. However, manual culture methods require a significant amount of labor and are prone to contamination, which can compromise the quality of the end product. Furthermore, there is no in-line process control, leading to substantial variability in quality between batches7. Taking stem cell therapy as an example, with a promising pipeline of over 200 stem-cell therapy candidates, it is estimated that 300 trillion hMSCs would be needed per year to meet the demands of clinical applications8. Hence, the large-scale manufacturing of therapeutic cells has become a prerequisite to perform these therapeutic interventions with such a high cell demand9.
To preclude the setbacks of planar systems, efforts have been made in developing large-scale manufacturing processes in stirred-tank bioreactors with conventional non-dissolvable microcarriers10,11,12,13, but these suffer from complicated preparation procedures and low cell-harvesting efficiency14. Recently, we have innovated a dissolvable microcarrier for stem cell expansion, aiming to circumvent the challenges of cell harvesting from conventional non-dissolvable commercial microcarriers15. This novel, commercially available GMP-grade 3D dissolvable porous microcarrier, 3D TableTrix, has shown great potential for large-scale cell production. Indeed, 3D culture based on these porous microcarriers could potentially recreate favorable biomimetic microenvironments to promote cell adhesion, proliferation, migration, and activation16. The porous structures and interconnected pore networks of microcarriers could create a larger cell adhesion area and promote the exchange of oxygen, nutrients, and metabolites, thus creating an optimal substrate for in vitro cell expansion17. The high porosity of these GMP-grade 3D dissolvable porous microcarriers enables large-scale expansion of hMSCs, and the ability for the cells to be fully dissolved allows for the efficient harvesting of these expanded cells18. It is also a GMP-grade product and has been registered as a pharmaceutical excipient with the Chinese Center for Drug Evaluation (filing numbers: F20210000003 and F20200000496)19 and the FDA of the United States (FDA, USA; Drug Master File number: 35481)20.
Here, we illustrate an automated closed industrial scale cell production (ACISCP) system18 using these dispersible and dissolvable porous microcarriers for hMSC, HEK293T cell, and Vero cell expansion. We achieved a successful two-tiered expansion of hMSCs (128 cumulative fold expansion in 9 days) from a 5 L bioreactor to a 15 L bioreactor and finally obtained up to 1.1 x 1010 hMSCs from a single batch of production. The cells were harvested by completely dissolving the microcarriers, concentrated, washed and formulated with a continuous flow centrifuge-based cell processing system, and then aliquoted with a cell filling system. Furthermore, we assessed the quality of hMSC products to confirm compliance. We also demonstrated the application of these dissolvable microcarriers for the scaled-up production of two other types of anchorage cells, HEK293T cells and Vero cells, that are extensively applied in the CGT industry. The peak cell density of HEK293T cells reached 1.68 x 107 cells/mL, whereas the peak density of Vero cells reached 1.08 x 107 cells/mL. The ACISCP system could be adapted to culture a variety of adherent cells, and it could potentially become a powerful platform contributing to expediting the industrialization of CGT.

저자 스포트라이트: Advancing Cell Therapy Manufacturing with Dissolvable Microcarriers 

GMP 등급의 용해성 다공성 마이크로캐리어를 기반으로 한 대규모 셀 생산

The cell and gene therapy industry has witnessed an exponential expansion over the past two decades. However, a large technological gap exists between lab research and industrial skill manufacturing. Compliant with regulatory policies, and to meet the green demands of the CGT industry, automated closed systems have been adopted to produce cell therapeutics.For adherent cells, cultivation using microcarriers in scalable stirred-tank bioreactors, is a promising method. Conventionally, commercialized microcarriers are non-desirable. Cell harvesting using trypsinization and the saving out microcarriers by size is not only inefficient and challenging, but also impacts cell quality and causes safety concerns.In this study, we have successfully achieved large-scale cell production based on GMP-grade 3D TableTrix dissolvable microcarriers in an automated and closed system. Over 11 billion human mesenchymal stem cells were yield in a two-stage expansion within nine days. We also demonstrated high density culture of HEK293T cells and Vero cells, in which both densities reached above 10 million cells per milliliter.This advanced biomanufacturing platform allows adherence cells to be effectively expanded and completely harvested in an automated and closed manner. Our protocol offers an opportunity to enhance production efficiency and refine quality control at industrial-scale manufacturing of CGT products.

ACISCP 플랫폼은 확장 확장을 위한 일련의 교반 탱크 바이오리액터, 자동화된 세포 수확 및 제형을 위한 세포 처리 시스템, 세포 주입 시스템을 사용하는 완전 폐쇄형 시스템입니다(그림 1). 부착 세포는 다공성 마이크로 캐리어에 부착되어 생물 반응기로 분산될 수 있으므로 부착 세포의 부유 배양을 달성할 수 있습니다.
설명된 프로토콜에 따라, 10g의 W01 ...

Watch this Scientific Journal Video about Advancing Cell Therapy Manufacturing with Dissolvable Microcarriers at JoVE.com

여기에서는 GMP 등급의 용해성 마이크로캐리어를 기반으로 하는 완전 폐쇄형 시스템을 통해 부착 세포의 대규모 제조를 달성하기 위한 프로토콜을 제시합니다. 인간 중간엽 줄기 세포, HEK293T 세포 및 Vero 세포의 배양은 검증되었으며 세포 및 유전자 치료 산업의 수량 요구와 품질 기준을 모두 충족했습니다.

Researchers in the cell and gene therapy (CGT) industry have long faced a formidable challenge in the efficient and large-scale expansion of cells. To ...

세포 및 유전자 치료 산업은 지난 20년 동안 기하급수적으로 확장되었습니다. 그러나 실험실 연구와 산업 기술 제조 사이에는 큰 기술적 격차가 존재합니다. 규제 정책을 준수하고 CGT 산업의 친환경 요구를 충족하기 위해 세포 치료제를 생산하기 위해 자동 폐쇄 시스템이 채택되었습니다.부착 세포의 경우, 확장 가능한 교반 탱크 바이오리액터에서 마이크로캐리어를 사용하여 배양하는 것이 유망한 방법입니다. 종래, 상용화된 마이크로캐리어는 바람직하지 않다. 트립신화를 사용한 세포 수확과 크기에 따른 마이크로캐리어 저장은 비효율적이고 까다로울 뿐만 아니라 세포 품질에 영향을 미치고 안전 문제를 야기합니다.이 연구에서 우리는 자동화된 폐쇄형 시스템에서 GMP 등급 3D TableTrix 용해성 마이크로캐리어를 기반으로 대규모 셀 생산을 성공적으로 달성했습니다. 110억 개 이상의 인간 중간엽 줄기세포가 9일 이내에 2단계 증식으로 수율되었습니다. 또한 HEK293T 세포와 Vero 세포의 고밀도 배양을 시연했는데, 두 세포 모두 밀리리터당 1,000만 개 이상의 세포에 도달했습니다.이 고급 바이오 제조 플랫폼을 사용하면 부착 세포를 효과적으로 확장하고 자동화되고 폐쇄된 방식으로 완전히 수확할 수 있습니다. 당사의 프로토콜은 CGT 제품의 산업 규모 제조에서 생산 효율성을 높이고 품질 관리를 개선할 수 있는 기회를 제공합니다.

GMP 등급의 용해성 다공성 마이크로캐리어를 기반으로 한 대규모 셀 생산

Abstract