1
|
Chaban V, de Boer E, McAdam KE, Vaage J, Mollnes TE, Nilsson PH, Pischke SE, Islam R. Escherichia coli-induced inflammatory responses are temperature-dependent in human whole blood ex vivo. Mol Immunol 2023; 157:70-77. [PMID: 37001293 DOI: 10.1016/j.molimm.2023.03.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 03/02/2023] [Accepted: 03/05/2023] [Indexed: 03/30/2023]
Abstract
Systemic inflammatory conditions are often associated with hypothermia or hyperthermia. Therapeutic hypothermia is used in post-cardiac arrest and some other acute diseases. There is a need for more knowledge concerning the effect of various temperatures on the acute inflammatory response. The complement system plays a crucial role in initiating the inflammatory response. We hypothesized that temperatures above and below the physiologic 37 °C affect complement activation and cytokine production ex vivo. Lepirudin-anticoagulated human whole blood from 10 healthy donors was incubated in the presence or absence of Escherichia coli at different temperatures (4 °C, 12 °C, 20 °C, 33 °C, 37 °C, 39 °C, and 41 °C). Complement activation was assessed by the terminal C5b-9 complement complex (TCC) and the alternative convertase C3bBbP using ELISA. Cytokines were measured using a 27-plex assay. Granulocyte and monocyte activation was evaluated by CD11b surface expression using flow cytometry. A consistent increase in complement activation was observed with rising temperature, reaching a maximum at 41 °C, both in the absence (C3bBbP p < 0.05) and presence (C3bBbP p < 0.05 and TCC p < 0.05) of E. coli. Temperature alone did not affect cytokine production, whereas incubation with E. coli significantly increased cytokine levels of IL-1β, IL-2, IL-6, IL-8, IFN-γ, and TNF at temperatures > 20 °C. Maximum increase occurred at 39 °C. However, a consistent decrease was observed at 41 °C, significant for IL-1β (p = 0.003). Granulocyte CD11b displayed the same temperature-dependent pattern as cytokines, with a corresponding increase in endothelial cell apoptosis and necrosis. Thus, blood temperature differentially determines the degree of complement activation and cytokine release.
Collapse
|
2
|
Khan AZ, Utheim TP, Jackson CJ, Tønseth KA, Eidet JR. Concise Review: Considering Optimal Temperature for Short-Term Storage of Epithelial Cells. Front Med (Lausanne) 2021; 8:686774. [PMID: 34485330 PMCID: PMC8416270 DOI: 10.3389/fmed.2021.686774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 07/08/2021] [Indexed: 11/23/2022] Open
Abstract
Transplantation of novel tissue-engineered products using cultured epithelial cells is gaining significant interest. While such treatments can readily be provided at centralized medical centers, delivery to patients at geographically remote locations requires the establishment of suitable storage protocols. One important aspect of storage technology is temperature. This paper reviews storage temperature for above-freezing point storage of human epithelial cells for regenerative medicine purposes. The literature search uncovered publications on epidermal cells, retinal pigment epithelial cells, conjunctival epithelial cells, corneal/limbal epithelial cells, oral keratinocytes, and seminiferous epithelial cells. The following general patterns were noted: (1) Several studies across different cell types inclined toward 4 and 16°C being suitable short-term storage temperatures. Correspondingly, almost all studies investigating 37°C concluded that this storage temperature was suboptimal. (2) Cell death typically escalates rapidly following 7–10 days of storage. (3) The importance of the type of storage medium and its composition was highlighted by some of the studies; however, the relative importance of storage medium vs. storage temperature has not been investigated systematically. Although a direct comparison between the included investigations is not reasonable due to differences in cell types, storage media, and storage duration, this review provides an overview, summarizing the work carried out on each cell type during the past two decades.
Collapse
Affiliation(s)
- Ayyad Zartasht Khan
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway.,Department of Surgery, Sørlandet Hospital Arendal, Arendal, Norway.,Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway.,Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway
| | - Tor Paaske Utheim
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway.,Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway.,Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.,Department of Ophthalmology, Stavanger University Hospital, Stavanger, Norway.,Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway.,Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Catherine Joan Jackson
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway.,Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.,Ifocus Eye Clinic, Haugesund, Norway
| | - Kim Alexander Tønseth
- Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.,Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
| | - Jon Roger Eidet
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| |
Collapse
|
3
|
Yazdani M, Shahdadfar A, Reppe S, Sapkota D, Vallenari EM, Lako M, Connon CJ, Figueiredo FC, Utheim TP. Response of human oral mucosal epithelial cells to different storage temperatures: A structural and transcriptional study. PLoS One 2020; 15:e0243914. [PMID: 33326470 PMCID: PMC7744058 DOI: 10.1371/journal.pone.0243914] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 11/30/2020] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Seeking to improve the access to regenerative medicine, this study investigated the structural and transcriptional effects of storage temperature on human oral mucosal epithelial cells (OMECs). METHODS Cells were stored at four different temperatures (4°C, 12°C, 24°C and 37°C) for two weeks. Then, the morphology, cell viability and differential gene expression were examined using light and scanning electron microscopy, trypan blue exclusion test and TaqMan gene expression array cards, respectively. RESULTS Cells stored at 4°C had the most similar morphology to non-stored controls with the highest viability rate (58%), whereas the 37°C group was most dissimilar with no living cells. The genes involved in stress-induced growth arrest (GADD45B) and cell proliferation inhibition (TGFB2) were upregulated at 12°C and 24°C. Upregulation was also observed in multifunctional genes responsible for morphology, growth, adhesion and motility such as EFEMP1 (12°C) and EPHA4 (4°C-24°C). Among genes used as differentiation markers, PPARA and TP53 (along with its associated gene CDKN1A) were downregulated in all temperature conditions, whereas KRT1 and KRT10 were either unchanged (4°C) or downregulated (24°C and 12°C; and 24°C, respectively), except for upregulation at 12°C for KRT1. CONCLUSIONS Cells stored at 12°C and 24°C were stressed, although the expression levels of some adhesion-, growth- and apoptosis-related genes were favourable. Collectively, this study suggests that 4°C is the optimal storage temperature for maintenance of structure, viability and function of OMECs after two weeks.
Collapse
Affiliation(s)
- Mazyar Yazdani
- Department of Medical Biochemistry, Oslo University Hospital, Ullevål, Oslo, Norway
- Center for Eye Research, Department of Ophthalmology, Oslo University Hospital, Ullevål, Oslo, Norway
| | - Aboulghassem Shahdadfar
- Center for Eye Research, Department of Ophthalmology, Oslo University Hospital, Ullevål, Oslo, Norway
| | - Sjur Reppe
- Department of Medical Biochemistry, Oslo University Hospital, Ullevål, Oslo, Norway
- Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
- Lovisenberg Diaconal Hospital, Unger-Vetlesen Institute, Oslo, Norway
| | - Dipak Sapkota
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Evan M. Vallenari
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Majlinda Lako
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, International Centre for Life, Bioscience West Building, Newcastle upon Tyne, United Kingdom
| | - Che J. Connon
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, International Centre for Life, Bioscience West Building, Newcastle upon Tyne, United Kingdom
| | - Francisco C. Figueiredo
- Biosciences Institute, Faculty of Medical Sciences, Newcastle University, International Centre for Life, Bioscience West Building, Newcastle upon Tyne, United Kingdom
- Department of Ophthalmology, Royal Victoria Infirmary & Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Tor Paaske Utheim
- Department of Medical Biochemistry, Oslo University Hospital, Ullevål, Oslo, Norway
- Department of Plastic and Reconstructive Surgery, Oslo University Hospital, Oslo, Norway
- Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
- Department of Ophthalmology, Stavanger University Hospital, Stavanger, Norway
- Department of Ophthalmology, Sørlandet Hospital Arendal, Arendal, Norway
- Department of Computer Science, Oslo Metropolitan University, Oslo, Norway
| |
Collapse
|
4
|
The Effects of Prolonged Storage on ARPE-19 Cells Stored at Three Different Storage Temperatures. Molecules 2020; 25:molecules25245809. [PMID: 33317020 PMCID: PMC7763992 DOI: 10.3390/molecules25245809] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2020] [Revised: 11/29/2020] [Accepted: 12/04/2020] [Indexed: 12/02/2022] Open
Abstract
This study aimed to investigate how prolonged storage of adult retinal pigment epithelial (ARPE-19) cell sheets affects cell metabolism, morphology, viability, and phenotype. ARPE-19 cell sheets were stored at three temperatures (4 °C, 16 °C, and 37 °C) for three weeks. Metabolic status and morphology of the cells were monitored by sampling medium and examining cells by phase-contrast microscopy, respectively, throughout the storage period. Cell viability was analyzed by flow cytometry, and phenotype was determined by epifluorescence microscopy after the storage. Lactate production and glucose consumption increased heavily, while pH dropped considerably, through storage at 37 °C compared to 4 °C and 16 °C. During storage, morphology started to deteriorate first at 4 °C, then at 37 °C, and was maintained the longest at 16 °C. Viability of the cells after three weeks of storage was best preserved at 16 °C, while cells stored at 4 °C and 37 °C had reduced viability. Dedifferentiation indicated by reduced expression of retinal pigment epithelium-specific protein 65 (RPE65), zonula occludens protein 1 (ZO-1), and occludin after three weeks of storage was noticed in all experimental groups compared to control. We conclude that storage temperature affects the metabolic status of ARPE-19 cells and that 16 °C reduces metabolic activity while protecting viability and morphology.
Collapse
|
5
|
Song Y, Wang B, Li H, Hu X, Lin X, Hu X, Zhang Y. Low temperature culture enhances ameloblastic differentiation of human keratinocyte stem cells. J Mol Histol 2019; 50:417-425. [PMID: 31278616 DOI: 10.1007/s10735-019-09837-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 06/30/2019] [Indexed: 10/26/2022]
Abstract
Previous studies have demonstrated that several types of human stem cells of non-dental origin can be induced to differentiate into enamel-secreting ameloblasts after recombined with mouse embryonic dental mesenchyme. However, the successful rate of ameloblastic differentiation is about rather low, which presents a major obstacle for future stem cell-based whole tooth bioengineering. Previous studies have shown that cultures at reduced temperature could improve the differentiation capability of stem cells in tissue engineering. In this study, we systematically investigated the effects of low temperature on the viability, proliferation and stemness of human keratinocytes stem cells (hKSCs) in cell culture and further examined ameloblastic differentiation of the hKSCs in human-mouse recombinant chimeric tooth germs. Our results demonstrated that low temperature indeed reduces growth rate and maintains healthy undifferentiated morphology of hKSCs without any effects on cell viability. Moreover, examination of stemness makers revealed improved stemness of hKSCs cultured at low temperature with increased expression of stemness markers K15, CD29 and p63 and decreased expression differentiation marker K10, as compared to those cultured at 37 °C. These low temperature treated hKSCs, when recombined with mouse embryonic dental mesenchyme, exhibited significantly increased rate (40%) of ameloblastic differentiation, as compared to that (17%) in tissue recombinants with those hKSCs treated at standard temperature. Our studies demonstrate that low temperature cell culture improves the stemness and plasticity of hKSCs, which in turn enhances ameloblastic differentiation capability of the stem cells in bioengineered teeth.
Collapse
Affiliation(s)
- Yingnan Song
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Bingmei Wang
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Hua Li
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Xiaoxiao Hu
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Xin Lin
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Xuefeng Hu
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China
| | - Yanding Zhang
- Southern Center for Biomedical Research, Fujian Key Laboratory of Developmental and Neural Biology, College of Life Sciences, Fujian Normal University, Fuzhou, 350108, Fujian, People's Republic of China.
| |
Collapse
|
6
|
Abstract
Human-induced pluripotent stem cells (hiPSCs) provide a personalized approach to study conditions and diseases including those of the eye that lack appropriate animal models to facilitate the development of novel therapeutics. Corneal disease is one of the most common causes of blindness. Hence, significant efforts are made to develop novel therapeutic approaches including stem cell-derived strategies to replace the diseased or damaged corneal tissues, thus restoring the vision. The use of adult limbal stem cells in the management of corneal conditions has been clinically successful. However, its limited availability and phenotypic plasticity necessitate the need for alternative stem cell sources to manage corneal conditions. Mesenchymal and embryonic stem cell-based approaches are being explored; nevertheless, their limited differentiation potential and ethical concerns have posed a significant hurdle in its clinical use. hiPSCs have emerged to fill these technical and ethical gaps to render clinical utility. In this review, we discuss and summarize protocols that have been devised so far to direct differentiation of human pluripotent stem cells (hPSCs) to different corneal cell phenotypes. With the summarization, our review intends to facilitate an understanding which would allow developing efficient and robust protocols to obtain specific corneal cell phenotype from hPSCs for corneal disease modeling and for the clinics to treat corneal diseases and injury.
Collapse
Affiliation(s)
| | - Rohit Shetty
- Cornea and Refractive Surgery, Narayana Nethralaya, Bengaluru, India
| | - Arkasubhra Ghosh
- GROW Research Laboratory, Narayana Nethralaya Foundation, Bengaluru, India
| |
Collapse
|
7
|
Optimization of Storage Temperature for Retention of Undifferentiated Cell Character of Cultured Human Epidermal Cell Sheets. Sci Rep 2017; 7:8206. [PMID: 28811665 PMCID: PMC5557837 DOI: 10.1038/s41598-017-08586-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2015] [Accepted: 07/17/2017] [Indexed: 11/11/2022] Open
Abstract
Cultured epidermal cell sheets (CES) containing undifferentiated cells are useful for treating skin burns and have potential for regenerative treatment of other types of epithelial injuries. The undifferentiated phenotype is therefore important for success in both applications. This study aimed to optimize a method for one-week storage of CES for their widespread distribution and use in regenerative medicine. The effect of storage temperatures 4 °C, 8 °C, 12 °C, 16 °C, and 24 °C on CES was evaluated. Analyses included assessment of viability, mitochondrial reactive oxygen species (ROS), membrane damage, mitochondrial DNA (mtDNA) integrity, morphology, phenotype and cytokine secretion into storage buffer. Lowest cell viability was seen at 4 °C. Compared to non-stored cells, ABCG2 expression increased between temperatures 8–16 °C. At 24 °C, reduced ABCG2 expression coincided with increased mitochondrial ROS, as well as increased differentiation, cell death and mtDNA damage. P63, C/EBPδ, CK10 and involucrin fluorescence combined with morphology observations supported retention of undifferentiated cell phenotype at 12 °C, transition to differentiation at 16 °C, and increased differentiation at 24 °C. Several cytokines relevant to healing were upregulated during storage. Importantly, cells stored at 12 °C showed similar viability and undifferentiated phenotype as the non-stored control suggesting that this temperature may be ideal for storage of CES.
Collapse
|
8
|
Utheim TP, Islam R, Fostad IG, Eidet JR, Sehic A, Olstad OK, Dartt DA, Messelt EB, Griffith M, Pasovic L. Storage Temperature Alters the Expression of Differentiation-Related Genes in Cultured Oral Keratinocytes. PLoS One 2016; 11:e0152526. [PMID: 27023475 PMCID: PMC4811429 DOI: 10.1371/journal.pone.0152526] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 03/15/2016] [Indexed: 12/17/2022] Open
Abstract
Purpose Storage of cultured human oral keratinocytes (HOK) allows for transportation of cultured transplants to eye clinics worldwide. In a previous study, one-week storage of cultured HOK was found to be superior with regard to viability and morphology at 12°C compared to 4°C and 37°C. To understand more of how storage temperature affects cell phenotype, gene expression of HOK before and after storage at 4°C, 12°C, and 37°C was assessed. Materials and Methods Cultured HOK were stored in HEPES- and sodium bicarbonate-buffered Minimum Essential Medium at 4°C, 12°C, and 37°C for one week. Total RNA was isolated and the gene expression profile was determined using DNA microarrays and analyzed with Partek Genomics Suite software and Ingenuity Pathway Analysis. Differentially expressed genes (fold change > 1.5 and P < 0.05) were identified by one-way ANOVA. Key genes were validated using qPCR. Results Gene expression of cultures stored at 4°C and 12°C clustered close to the unstored control cultures. Cultures stored at 37°C displayed substantial change in gene expression compared to the other groups. In comparison with 12°C, 2,981 genes were differentially expressed at 37°C. In contrast, only 67 genes were differentially expressed between the unstored control and the cells stored at 12°C. The 12°C and 37°C culture groups differed most significantly with regard to the expression of differentiation markers. The Hedgehog signaling pathway was significantly downregulated at 37°C compared to 12°C. Conclusion HOK cultures stored at 37°C showed considerably larger changes in gene expression compared to unstored cells than cultured HOK stored at 4°C and 12°C. The changes observed at 37°C consisted of differentiation of the cells towards a squamous epithelium-specific phenotype. Storing cultured ocular surface transplants at 37°C is therefore not recommended. This is particularly interesting as 37°C is the standard incubation temperature used for cell culture.
Collapse
Affiliation(s)
- Tor Paaske Utheim
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
- Department of Ophthalmology, Vestre Viken HF Trust, Drammen, Norway
- Faculty of Health Sciences, National Centre for Optics, Vision and Eye Care, Buskerud and Vestfold University College, Kongsberg, Norway
| | - Rakibul Islam
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Ida G. Fostad
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Jon R. Eidet
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- Department of Ophthalmology, Oslo University Hospital, Oslo, Norway
| | - Amer Sehic
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - Ole K. Olstad
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
| | - Darlene A. Dartt
- Schepens Eye Research Institute, Massachusetts Eye and Ear, Harvard Medical School, Boston, Massachusetts, United States of America
| | - Edward B. Messelt
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway
| | - May Griffith
- Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden
| | - Lara Pasovic
- Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
- Faculty of Medicine, University of Oslo, Oslo, Norway
- * E-mail:
| |
Collapse
|
9
|
Sehic A, Utheim ØA, Ommundsen K, Utheim TP. Pre-Clinical Cell-Based Therapy for Limbal Stem Cell Deficiency. J Funct Biomater 2015; 6:863-88. [PMID: 26343740 PMCID: PMC4598682 DOI: 10.3390/jfb6030863] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Revised: 08/10/2015] [Accepted: 08/21/2015] [Indexed: 12/13/2022] Open
Abstract
The cornea is essential for normal vision by maintaining transparency for light transmission. Limbal stem cells, which reside in the corneal periphery, contribute to the homeostasis of the corneal epithelium. Any damage or disease affecting the function of these cells may result in limbal stem cell deficiency (LSCD). The condition may result in both severe pain and blindness. Transplantation of ex vivo cultured cells onto the cornea is most often an effective therapeutic strategy for LSCD. The use of ex vivo cultured limbal epithelial cells (LEC), oral mucosal epithelial cells, and conjunctival epithelial cells to treat LSCD has been explored in humans. The present review focuses on the current state of knowledge of the many other cell-based therapies of LSCD that have so far exclusively been explored in animal models as there is currently no consensus on the best cell type for treating LSCD. Major findings of all these studies with special emphasis on substrates for culture and transplantation are systematically presented and discussed. Among the many potential cell types that still have not been used clinically, we conclude that two easily accessible autologous sources, epidermal stem cells and hair follicle-derived stem cells, are particularly strong candidates for future clinical trials.
Collapse
Affiliation(s)
- Amer Sehic
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Sognsvannsveien 10, Oslo 0372, Norway.
| | - Øygunn Aass Utheim
- Department of Ophthalmology, Oslo University Hospital, Kirkeveien 166, Oslo 0407, Norway.
| | - Kristoffer Ommundsen
- Department of Medical Biochemistry, Oslo University Hospital, Kirkeveien 166, Oslo 0407, Norway.
| | - Tor Paaske Utheim
- Department of Oral Biology, Faculty of Dentistry, University of Oslo, Sognsvannsveien 10, Oslo 0372, Norway.
- Department of Medical Biochemistry, Oslo University Hospital, Kirkeveien 166, Oslo 0407, Norway.
| |
Collapse
|