Editing Transdifferentiation (section)

=== Method of transfection ===

In order to accomplish [[transfection]], one may use integrating [[viral vector]]s such as [[lentivirus]]es or [[retrovirus]]es, non-integrating vectors such as [[Sendai virus]]es or [[Adenoviridae|adenoviruses]], [[microRNA]]s and a variety of other methods including using proteins and [[plasmid]]s;<ref>{{Cite journal 
| last1 = Patel | first1 = M. 
| last2 = Yang | first2 = S. 
| doi = 10.1007/s12015-010-9123-8 
| title = Advances in Reprogramming Somatic Cells to Induced Pluripotent Stem Cells 
| journal = Stem Cell Reviews and Reports 
| volume = 6 
| issue = 3 
| pages = 367–380 
| year = 2010 
| pmid = 20336395 
| pmc =2924949 
}}</ref> one example is the non-viral delivery of transcription factor-encoding plasmids with a polymeric carrier to elicit neuronal transdifferentiation of fibroblasts.<ref>{{Cite journal 
| last1 = Adler | first1 = A. F. 
| last2 = Grigsby | first2 = C. L. 
| last3 = Kulangara | first3 = K. 
| last4 = Wang | first4 = H. 
| last5 = Yasuda | first5 = R. 
| last6 = Leong | first6 = K. W. 
| doi = 10.1038/mtna.2012.25 
| title = Nonviral Direct Conversion of Primary Mouse Embryonic Fibroblasts to Neuronal Cells 
| journal = Molecular Therapy: Nucleic Acids 
| volume = 1 
| issue = 7 
| pages = e32– 
| year = 2012 
| pmid = 23344148 
| pmc =3411320 
}}</ref> When foreign molecules enter cells, one must take into account the possible drawbacks and potential to cause tumorous growth. Integrating viral vectors have the chance to cause mutations when inserted into the genome. One method of going around this is to excise the viral vector once reprogramming has occurred, an example being [[Cre-Lox recombination]]<ref>{{Cite journal 
| last1 = Sommer | first1 = C. A. 
| last2 = Sommer | first2 = A. 
| last3 = Longmire | first3 = T. A. 
| last4 = Christodoulou | first4 = C. 
| last5 = Thomas | first5 = D. D. 
| last6 = Gostissa | first6 = M. 
| last7 = Alt | first7 = F. W. 
| last8 = Murphy | first8 = G. J. 
| last9 = Kotton | first9 = D. N. 
| doi = 10.1002/stem.255 
| last10 = Mostoslavsky | first10 = G. 
| title = Excision of Reprogramming Transgenes Improves the Differentiation Potential of iPS Cells Generated with a Single Excisable Vector 
| journal = Stem Cells 
| volume = 28 
| issue = 1 
| pages = 64–74 
| year = 2009 
| pmid = 19904830 
| pmc =  4848036}}</ref> Non-integrating vectors have other issues concerning efficiency of reprogramming and also the removal of the vector.<ref>{{Cite journal 
| last1 = Zhou | first1 = W. 
| last2 = Freed | first2 = C. R. 
| doi = 10.1002/stem.201 
| title = Adenoviral Gene Delivery Can Reprogram Human Fibroblasts to Induced Pluripotent Stem Cells 
| journal = Stem Cells 
| volume = 27 
| issue = 11 
| pages = 2667–2674 
| year = 2009 
| pmid = 19697349 
| doi-access = free 
}}</ref> Other methods are relatively new fields and much remains to be discovered.