In recent years, a huge revolution has been underway in the field of biotechnology and biomedical research. A fundamental role in this revolution is played by biopharmaceutical products. The peripheral blood mononuclear cells are mainly represented by monocytes and lymphocytes. These cells have been shown to play an essential role in the stages of tissue regeneration and neovascularization. Critical limb ischemia (CLI), characterized by rest pain with or without tissue loss due to inadequate blood perfusion to the affected extremities, is considered the most serious form of peripheral arterial disease (PAD) and can often lead to ulceration and amputation of the lower limbs. For over 15 years, attempts have been made to study effective cell therapy for this type of disease, with approaches that can be included in the category of regenerative medicine. In particular, peripheral blood mononuclear cells (PBMCs) and bone marrow mononuclear cells (BM-MNCs) have been the most studied and the most promising for the treatment of this disease. By comparing the two sources, however, the PBMCs represent a more accessible, easily isolated, in addition to being less painful, less invasive and risky than BM-MNCs. Despite the positive experimental results found with clinical trials using PBMCs, currently on the market the methods for isolation and manipulation, which mainly use medical devices, are impractical for use in the operating room, in addition to being scarcely selective. The aim of this work is the preclinical development of a GMP-upgradable method, for the production of an ATMPs based on peripheral blood mononuclear cells, for the treatment of critical limb ischemia. In order to achieve this, the work was divided into the following points. • Development of the PBMCs extraction process from peripheral blood, varying washing method, to obtain the maximum yield. • Test on thawing wash method, to obtain the maximum recovery of cryopreservation cells. • Storage stability of cells in liquid nitrogen, based on two different serum-free cryomedia, with the aim of identifying the best for their conservation. • Identification of the key parameters for the transport of blood from the clinic to the GMP facility and of the finished product to the clinic. • Development of a potency test on in vitro cultures, based on the production of VEGF, a fundamental cytokine in neovascularization through an enzyme-linked immunosorbent assay (ELISA), under conditions of normoxia and hypoxia. The results allowed to observe how a higher centrifugation speed and the presence of albumin in the washing solution is decisive in the extraction yield of the PBMCs, after isolation from peripheral blood, without affecting the viability. The two cell subgroups that benefit most are monocytes and lymphocytes. Also with regard to thawing, the variation of the two parameters mentioned allow for greater recovery without affecting the viability, in this case, however, monocytes, platelets and B lymphocytes benefit significantly. For the two tested serum-free cryomedia, which differ from each other because one contains HSA and the other autologous plasma, no differences were observed in the short period of cryopreservation. The blood transport and ATMP parameters proved to be decisive for the success of the finished product, and were identified in a maximum transport period of 8 hours at room temperature (20-22 ° C) for blood; and for a maximum period of 24 hours with a range of 2-6 °C for PBMCs product. Furthermore, an inexpensive and effective system has been developed with success for the hypoxic pre-conditioning of cultured cells using sterile plastic bags. Finally, the potency test showed how in the VEGF secretion there can be heterogeneity between batches and a significant difference between cultures in normoxic compared to hypoxic conditions.
Negli ultimi anni è stata avviata una grande rivoluzione nel campo della biotecnologia. Un ruolo fondamentale in questa rivoluzione è svolto dai prodotti biofarmaceutici. Le cellule mononucleate del sangue periferico sono rappresentate principalmente da monociti e linfociti. È stato dimostrato che queste cellule svolgono un ruolo essenziale nelle fasi di rigenerazione e neo-vascolarizzazione dei tessuti. L'ischemia critica degli arti (CLI), caratterizzata da dolore a riposo con o senza perdita di tessuto dovuta a inadeguata perfusione del sangue alle estremità colpite. Sono stati eseguiti studi di una terapia cellulare efficace per questo tipo di malattia.In particolare, le cellule mononucleate del sangue periferico (PBMC) e le cellule mononucleari del midollo osseo (BM-MNC) sono state le più studiate e le più promettenti per il trattamento di questa malattia. Confrontando le due fonti, tuttavia, le PBMC rappresentano una più accessibile, facilmente isolata, oltre ad essere meno dolorosa, meno invasiva e rischiosa delle BM-MNC. Nonostante i risultati sperimentali positivi riscontrati con studi clinici che utilizzano PBMC, attualmente sul mercato i metodi di isolamento e manipolazione, che utilizzano principalmente dispositivi medici, sono poco pratici per l'uso in sala operatoria, oltre ad essere scarsamente selettivi. Lo scopo di questo lavoro è lo sviluppo pre-clinico di un metodo aggiornabile GMP, per la produzione di un ATMP basato su cellule mononucleate del sangue periferico, per il trattamento dell'ischemia critica degli arti. Per raggiungere questo obiettivo, il lavoro è stato suddiviso nei seguenti punti. • Sviluppo del processo di estrazione dei PBMC dal sangue periferico, variando il metodo di lavaggio, per ottenere la massima resa. • Test sul metodo di lavaggio con scongelamento, per ottenere il massimo recupero delle cellule di crioconservazione. • Stabilità allo stoccaggio delle cellule in azoto liquido, basato su due differenti cryomedia prive di siero, con l'obiettivo di identificare il meglio per la loro conservazione. • Identificazione dei parametri chiave per il trasporto di sangue dalla clinica alla struttura GMP e del prodotto finito alla clinica. • Sviluppo di un test di potenza su colture in vitro, basato sulla produzione di VEGF, una citochina fondamentale nella neovascolarizzazione attraverso un saggio di immunoassorbimento enzimatico (ELISA), in condizioni di normossia e ipossia. I risultati hanno permesso di osservare come una maggiore velocità di centrifugazione e la presenza di albumina nella soluzione di lavaggio sia decisiva nella resa di estrazione dei PBMC, dopo l'isolamento dal sangue periferico, senza influire sulla vitalità. I due sottogruppi di cellule che ne beneficiano maggiormente sono monociti e linfociti. Anche per quanto riguarda lo scongelamento, la variazione dei due parametri citati consente un maggiore recupero senza compromettere la vitalità, in questo caso, tuttavia, i monociti, le piastrine e i linfociti B beneficiano in modo significativo. Per i due terreni senza siero testati, che differiscono l'uno dall'altro perché uno contiene HSA e l'altro plasma autologo, non sono state osservate differenze nel breve periodo di crioconservazione. I parametri di trasporto del sangue e ATMP si sono dimostrati decisivi per il successo del prodotto finito e sono stati identificati in un periodo di trasporto massimo di 8 ore a temperatura ambiente (20-22 ° C) per il sangue; e per un periodo massimo di 24 ore con un intervallo di 2-6 ° C per il prodotto PBMC. Inoltre, è stato sviluppato con successo un sistema economico ed efficace per il pre-condizionamento ipossico delle cellule in coltura utilizzando sacchetti di plastica sterili. Infine, il test di potenza ha mostrato come nella secrezione di VEGF ci possa essere eterogeneità tra i lotti e una differenza significativa tra le colture in condizioni normossiche rispetto alle condizioni ipossiche.
Sviluppo preclinico di un metodo espandibile in GMP di cellule mononucleate del sangue periferico per il trattamento dell'ischemia critica degli arti
CUSUMANO, GIUSEPPE
2018/2019
Abstract
In recent years, a huge revolution has been underway in the field of biotechnology and biomedical research. A fundamental role in this revolution is played by biopharmaceutical products. The peripheral blood mononuclear cells are mainly represented by monocytes and lymphocytes. These cells have been shown to play an essential role in the stages of tissue regeneration and neovascularization. Critical limb ischemia (CLI), characterized by rest pain with or without tissue loss due to inadequate blood perfusion to the affected extremities, is considered the most serious form of peripheral arterial disease (PAD) and can often lead to ulceration and amputation of the lower limbs. For over 15 years, attempts have been made to study effective cell therapy for this type of disease, with approaches that can be included in the category of regenerative medicine. In particular, peripheral blood mononuclear cells (PBMCs) and bone marrow mononuclear cells (BM-MNCs) have been the most studied and the most promising for the treatment of this disease. By comparing the two sources, however, the PBMCs represent a more accessible, easily isolated, in addition to being less painful, less invasive and risky than BM-MNCs. Despite the positive experimental results found with clinical trials using PBMCs, currently on the market the methods for isolation and manipulation, which mainly use medical devices, are impractical for use in the operating room, in addition to being scarcely selective. The aim of this work is the preclinical development of a GMP-upgradable method, for the production of an ATMPs based on peripheral blood mononuclear cells, for the treatment of critical limb ischemia. In order to achieve this, the work was divided into the following points. • Development of the PBMCs extraction process from peripheral blood, varying washing method, to obtain the maximum yield. • Test on thawing wash method, to obtain the maximum recovery of cryopreservation cells. • Storage stability of cells in liquid nitrogen, based on two different serum-free cryomedia, with the aim of identifying the best for their conservation. • Identification of the key parameters for the transport of blood from the clinic to the GMP facility and of the finished product to the clinic. • Development of a potency test on in vitro cultures, based on the production of VEGF, a fundamental cytokine in neovascularization through an enzyme-linked immunosorbent assay (ELISA), under conditions of normoxia and hypoxia. The results allowed to observe how a higher centrifugation speed and the presence of albumin in the washing solution is decisive in the extraction yield of the PBMCs, after isolation from peripheral blood, without affecting the viability. The two cell subgroups that benefit most are monocytes and lymphocytes. Also with regard to thawing, the variation of the two parameters mentioned allow for greater recovery without affecting the viability, in this case, however, monocytes, platelets and B lymphocytes benefit significantly. For the two tested serum-free cryomedia, which differ from each other because one contains HSA and the other autologous plasma, no differences were observed in the short period of cryopreservation. The blood transport and ATMP parameters proved to be decisive for the success of the finished product, and were identified in a maximum transport period of 8 hours at room temperature (20-22 ° C) for blood; and for a maximum period of 24 hours with a range of 2-6 °C for PBMCs product. Furthermore, an inexpensive and effective system has been developed with success for the hypoxic pre-conditioning of cultured cells using sterile plastic bags. Finally, the potency test showed how in the VEGF secretion there can be heterogeneity between batches and a significant difference between cultures in normoxic compared to hypoxic conditions.È consentito all'utente scaricare e condividere i documenti disponibili a testo pieno in UNITESI UNIPV nel rispetto della licenza Creative Commons del tipo CC BY NC ND.
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https://hdl.handle.net/20.500.14239/11601