Editing Protein production (section)

===== Non-lytic insect cell expression =====
Non-lytic insect cell expression is an alternative to the lytic baculovirus expression system. In non-lytic expression, vectors are transiently or stably [[Transfection|transfected]] into the chromosomal DNA of insect cells for subsequent gene expression.<ref name=Dyring>{{cite journal | last1 = Dyring | first1 = Charlotte | year = 2011 | title = Optimising the drosophila S2 expression system for production of therapeutic vaccines | journal = BioProcessing Journal | volume = 10 | issue = 2| pages = 28–35 | doi=10.12665/j102.dyring}}</ref><ref name=Olczak>{{cite journal | vauthors = Olczak M, Olczak T | title = Comparison of different signal peptides for protein secretion in nonlytic insect cell system | journal = Analytical Biochemistry | volume = 359 | issue = 1 | pages = 45–53 | date = December 2006 | pmid = 17046707 | doi = 10.1016/j.ab.2006.09.003 }}</ref> This is followed by selection and screening of recombinant clones.<ref name=McCarroll>{{cite journal | vauthors = McCarroll L, King LA | title = Stable insect cell cultures for recombinant protein production | journal = Current Opinion in Biotechnology | volume = 8 | issue = 5 | pages = 590–4 | date = October 1997 | pmid = 9353223 | doi = 10.1016/s0958-1669(97)80034-1 }}</ref> The non-lytic system has been used to give higher protein yield and quicker expression of recombinant genes compared to baculovirus-infected cell expression.<ref name=Olczak /> Cell lines used for this system include: [[Sf9 (cells)|Sf9]], [[Sf21]] from ''[[Spodoptera frugiperda]]'' cells, [[High Five cells|Hi-5]] from ''[[Cabbage looper|Trichoplusia ni]]'' cells, and [[Schneider 2 cells]] and Schneider 3 cells from ''[[Drosophila melanogaster]]'' cells.<ref name=Dyring /><ref name=McCarroll /> With this system, cells do not lyse and several cultivation modes can be used.<ref name=Dyring /> Additionally, protein production runs are reproducible.<ref name=Dyring /><ref name=Olczak /> This system gives a homogeneous product.<ref name=Olczak /> A drawback of this system is the requirement of an additional screening step for selecting viable [[Clone (cell biology)|clones]].<ref name=McCarroll />