Stem cells and cell therapy

Transcription

1 Stem cells and cell therapy lecture

2 What is a stem cell? Stem cell can differentiate into two or more cell types Progenitor cells differentiates into single cell type 2

3 Sources of stem or progenitor cells embryonic somatic

4 Classification of SCs 1. Based on the tissue commitment/ differentation capacity Totipotent SCs - zygote Pluripotent SCs Multipotent SCs Unipotent SCs (Tissue progenitors) 2. Based on their origin Embryonic SCs (ESCs) Fetal SC ( adult SC) Umbilical cord blood stem cells ( adult ) Postnatal - Adult SCs Reprogrammed SCs (Inducible Pluripotent SCs = ips cells)

5 Stem cells 1. Embryonic stem cells (ESC) 2. Somatic ( adult ) stem cells 2.1. Fetal, tissue specific stem cells 2.2. Umbilical cord bloods stem cells 2.3. bone marrow hematopoietic mesenchymal proangiogenic (endothelial) progenitor cells 2.4. skin 2.5. nervous (brain) 2.6. intestine 2.7. other adult, organ specific (heart, fat tissue) 2.8. embryonal carcinoma cells 3. Tumor stem cells

6 What are embryonic stem cells? - develop from eggs fertilized in vitro - derived from 4-5 days old embryos - isolated from ~ 8 cell embryo or inner cell mass

7 Human embryonic stem cells Obtained in 1998 by J. Thompson The National Institutes of Health resource for stem cell research

8 Embryonic stem cells are pluripotent Human ESC, after being differentiated to a specific cell type, can be potentially used for the therapy 9

9 Stem cells in therapy examples

10 Neuronal stem cells and Parkinson Disease Neurodegenerative disease - loss of dopamine neurons Fourth most common neurodegenerative disease Who is under the risk? 1% of people > 65 years 0.4% of people > 40 years

11 Symptoms of PD

12 Clinical study Transplantation of embryonic dopamine neurons for severe Parkinson s Disease Dopamine neurons in embryonic tissue In vitro culture for 4 weeks Transplantation Control group: sham surgery

13 Aim of the study To check: if implanted neurons survive if they lead to improvement of PD if age affect the outcome of the therapy

14 Results Transplanted cells survived Growth of the transplants was observed

15 Clinical study Freed CR et al. N Engl J Med Mar 8;344(10):710-9.

16 Clinical effects Intraarterial autologous implantation of adult stem cells for patients with Parkinson disease (Brazzini Aet al. Vasc Interv Radiol. 2010; 21: ) 36 men and 14 women with PD underwent autologous implantation of stem cells with arterial catheterization. Comparison was made versus data collected before treatment. Patients showed a significant improvement in disability, activities of daily living, depression, and quality of life. No complications were observed. Open-labeled study of unilateral autologous bone-marrow-derived mesenchymal stem cell transplantation in Parkinson's disease. (Venkataramana et al. Transl Res. 2010; 155: 62-70). Seven PD patients were enrolled to participate in the prospective, uncontrolled, pilot study of single-dose, unilateral transplantation of autologous bone-marrow-derived mesenchymal stem cells (BM-MSCs). The BM-MSCs were transplanted into the sublateral ventricular zone by stereotaxic surgery. Patients were followed up for a period that ranged from 10 to 36 months. A subjective improvement was found in symptoms like facial expression, and freezing episodes; 2 patients have significantly reduced the dosages of PD medicine. Be careful with interpretation

17 Embryonic stem cells are pluripotent Human ESC, after being differentiated to a specific cell type, can be potentially used for the therapy 9

18 Embryonic stem cells in therapy of human diseases

19 Important! In therapy no one will use un-differentiated embryonic stem cells! The ESC before application to human are differentiated to the specific cell type However, the risk of contamination with un-diiferentiated (not fully differentiated) ESC exists There is always a risk of rejection of transplanted cells due to genetic differences with the host

20 Oligodendrocytes from hesc - Oligodendrocytes have several functions: * produce myelin * produce neurotrophic factors - Oligodendrocytes are lost in spinal cord injury, resulting in myelin and neuronal loss that cause paralysis in many patients with spinal cord injuries. oligodendrocytes grown on axons in culture

21 Embryonic stem cell-based therapy - GRNOPC1 contains hesc-derived oligodendrocyte progenitor cells. - The cells have demonstrated remyelinating and nerve growth stimulating properties leading to restoration of function in animal models of acute spinal cord injury. - Preclinical studies showed that administration of GRNOPC1 significantly improved locomotor activity and kinematic scores of animals with spinal cord injuries when injected seven days after the injury. - Histological examination of the injured spinal cords treated with GRNOPC1 showed improved axon survival and extensive remyelination surrounding the rat axons.

22 Embryonic stem cells in therapy Geron Corp. - USA clinical trial in patients after severe spinal cord injury ESCs differentiated to oligodendrocytes (halted: The Scientist, ) Adcanced Cell Technology (ACT) Statdgard s blindness affects humans at years, uncurable ESCs differentiated to pigment epithelial cells Science 30 September 2011 Problem: genetic disparity of stem cells and host

23 Human ESC ethical and practical problems 1. Classic ESC are genetically different from the host 2. Side effects teratocarcinoma formation 3. ESC are obtained from the surpluss embryos generated by in vitro fertilisation (for reproductive purposes) (in vitro fertiliation only for research pursposes is forbidden in most countries) 4. Ethical problems for belivers that human entity starts from the conception

24 What about adult stem cells in therapy?

25 Stem cells in therapy 1. Hematopoietic stem cells (bone-marrow, cord blood (leukemias, immunodeficiencies, anemias but also other, like Krabbe s diseases, adrenoleukodytrophy) 2. Skin stem cells (burns, ulcers) 3. Endothelial progenitor cells and others therapy of myocardial infarctions 4. Neural stem cells Parkinson disease, Alzheimer disease 5. Bone marrow cells for treatment of diabetes type I

26 Limbal stem cells in treatment of blindess caused by damage (mostly burn-caused) The autologous limbal cells were used for the transplantation Permanent restoration of a transparent, renewing corneal epithelium was attained in 76.6% of eyes. The failures occurred within the first year. Restored eyes remained stable over time, with up to 10 years of follow-up (mean, 2.91±1.99; median, 1.93). P. Rama (G. Pellegrini) et al., NEJM 2010

27 Hematopoietic stem cells in vivo bone marrow cord blood peripheral blood

28 Isolation of HSC

29 Isolation of HSC 2. Peripheral blood mobilization continuos blood flow up to 20 L are proceed during one aspiration

30 Autologous transplantation of HSC - procedure

31 II. Stem cells in cardiac regeneration Coronary heart disease Ischemia limitation of blood flow - cell starvation Myocardial infarction (heart attack) lack of blood - death of myocardial muscles Occlusion of the artery Rapid ischemia Apoptosis of myocytes Collagen replacement - fibrous tissue Expansion of the infarct zone

32 Delivery Application of stem cells

33 Intracoronary Infusion of Bone-Marrow-Derived Progenitor Cells is Associated with Improved Clinical Outcome in Patients with Acute Myocardial Infarction Schächinger et al. Circulation 2006.

34 Hematopoietic stem cells for treatment of type 1 DM HSC mobilization HSC propagation HSC collecting reinfusion of the collected cells strong immunosuppresion "Autologous nonmyeloablative hematopietic stem cell transplantation in newly diagnosed type 1 diabetes melitus" Conclusion: 14 of 15 patients became insulin-free (7- to 36-month follow-up) for at least 6 months (1 for 35 months). Serum levels of HBA1c were maintained at less than 7% in 13 patients. "C-peptide levels and insulin independence following autologous nonmyeloablative hematopietic stem cell transplantation in newly diagnosed type 1 diabetes melitus " Conclusion: After a follow-up of 29.8 months C-peptide levels increased significantly and the majority of patients achieved insulin independence with good glycaemic control. Voltarelli et al. JAMA 2007 and JAMA 2009

35 Healing the burn or diabetic wounds Stem cells proliferation is the key step in wound healing Supply of stem cells: basal layer of epidermis bulge sebaceous glands

36 Tissue engineering - Tissue engineering combines advances in cell biology and materials science. These tissues consist of biocompatible scaffolding material, plus living cells grown using cell culture techniques. * Simple tissues, such as skin and cartilage, were the first to be engineered successfully.

37 SC and burns treatment Cells characterisation: Easy to isolate Easy to culture human keratinocytes Dr Justyna Drukała

38 Skin autografts` 1. Skin biopsy 2. Expansion of cells in vitro Dr Justyna Drukała

39 3. Preparation of cells Skin autografts trombina fibrynogen

40 Examples from the clinic Ulcers Dr Justyna Drukała

41 embryonic vs adult in terms of cell therapy potency telomerase expression embryonic SC pluripotent yes adult SC unipotent multipotent no culturing easily grown hard to obtain large numbers of cells stem cell therapy rejection problem no rejection problem

42 Is the other way round possible? Human Dermal Fibroblasts Stem Cell

43 Induced pluripotent stem cells indukowane pluripotencjalne komórki macierzyste (ips) hinya Yamanaka 2006

44 Mouse fibroblasts reprogrammed to ipscs Mouse ips obtained after OSKM gene transfer to fibroblasts Positive for alkaline phosphatase J. Stępniewski i wsp, 2011

45 Transcription-factor induced pluripotency Induced pluripotent stem cells (ips) Yamanaka et al Zaehres & Scholler, Cell 2008 Differentiation into ecto, endo and mesoderm

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47 Transcritpion-factor induced transdifferentiation T. Graf, Cell Stem Cell, December 2011

48 Thank you