Contributor:

Sarnowska, Anna (Promotor)

Publisher:

Instytut Medycyny Doświadczalnej i Klincznej im. M. Mossakowskiego PAN

Place of publishing:

Warszawa

Degree name:

doctor

Level of degree:

2

Degree discipline :

medical sciences

Abstract:

The dynamic development of regenerative medicine is possible, among others, due to the stem cells application. Their therapeutic effect include trophic, anti-inflammatory and immunomodulatory properties. The current state of knowledge about the stem cells' properties allows us properly select the source and method of obtaining cells to treat patients with a specific medical condition. Nevertheless, in most cases, the number of freshly isolated cells is still the restrictive factor leading to the need to multiply the material in vitro. Cell culture is still accompanied by the cell senescence that slows down their proliferation, decreasing of trophic and immunomodulatory properties, and finally increases the probability of damage and mutations in the genetic material of cells that can lead to neoplastic transformation. Therefore, further work is needed to standardize the isolation and long-term cell culture conditions. The cellular material for the conducted experiments were two cell fractions obtained from adipose tissue: mesenchymal stromal/stem cells (ASC) obtained by the enzymatic method, and differentiated fat cells (DFAT) by the so-called ceiling culture. The main aim of the conducted research was to optimize the in vitro conditions enabling the acquisition of an appropriate number of cells while maintaining their biological safety and the desired therapeutic properties. The detailed purposes included the characterization of both the above-mentioned adipose tissue-derived stem cell populations in the target groups of environmental conditions and the comparison of their therapeutic properties (secretory, protective and repopulation), including the verification of their mechanism of action and the clinical safety of their use. The conducted experiments included the property analysis of mesenchymal stem cells obtained from adipose tissue: ASC and DFAT cells’ cultivation in various aerobic conditions - 5% O2 and 21% O2.The obtained results confirmed the mesenchymal and multipotential nature of both analyzed fractions. Moreover, they also indicated that the conditions of 5% O2 compared to the 21% O2, determine a faster and simultaneously a stable rate of proliferation with the maintenance of normal morphology and a slower increase of β-galactosidase activity as well as a lower risk of neoplastic transformation. The pluripotent properties assessed in terms of SRTF (stemnes-related transcriptional factors) expression are more strongly expressed by DFAT was indicated. The protective effect of ASC and DFAT, the potential of these cells for neural differentiation and the secretion of anti-inflammatory and growth factors were confirmed in the co-culture model of studied cells with organotypic culture of rat hippocampal slices. Based on the obtained preclinical data on the mechanisms of ASC interaction in the environment of the damaged nervous tissue, an experimental administration of the non-passaged cells was carried out in three diseases: the secondary nerve release after a traumatic nerve injury and the unsuccessful reconstruction attempt, amyotrophic lateral sclerosis and autoimmune refractory epilepsy. The periprocedural and a 5-year follow-up, confirmed the safety of the used cell therapy and also indicated the need of cell injections repetition in order to maintain the achieved therapeutic effect. Observed cytokine release in CSF and reported clinical improvement of the patient persisting up to 3 months after cell administration. The obtained results have indicated the validity of mesenchymal stem cell therapy based on their secretory influence. Furthermore, the material for clinical application can be effectively multiplied in vitro under closed to physiological oxygen concentration in stem cell niche. This allows the long-term maintenance of cells in a state of high proliferative activity while ensuring genetic stability, which is the fundamental requisite of their biological safety during clinical application.

Detailed Resource Type:

PhD Dissertations

Resource Identifier:

oai:rcin.org.pl:236065

Source:

IMDiK PAN, sygn. ZS 414

Language:

pol

Language of abstract:

eng

Rights:

Rights Reserved - Restricted Access

Digitizing institution:

Mossakowski Medical Research Institute PAS

Original in:

Library of the Mossakowski Medical Research Institute PAS

Projects co-financed by:

Program Operacyjny Polska Cyfrowa, lata 2014-2020, Działanie 2.3 : Cyfrowa dostępność i użyteczność sektora publicznego; środki z Europejskiego Funduszu Rozwoju Regionalnego oraz współfinansowania krajowego z budżetu państwa

Access:

Closed