Mammal Cell free Expression Service

Alpha Lifetech Inc. focuses on recombinant proteins' expression in different Biosystems for many years, including prokaryotic and eukaryotic organisms, as well as the development of novel high-potency recombinant proteins.

Alpha Lifetech Inc. provides a reliable expression of membrane proteins to meet native configuration and functional requirements by using a cell-free protein expression system. Conventional methods in vivo, such as Mammal Expression System, Insect Expression System, Bacteria Expression System and Yeast Expression System, for the production of integral membrane proteins have intrinsic limits in membrane proteins' expression, because the production of membrane proteins is a challenging task as their hydrophobic nature and their specific requirements in cellular expression systems frequently prevent an efficient synthesis. So far, a considerable number of membrane proteins from diverse families like prokaryotic small multidrug transporters (SMTs) or eukaryotic G-protein coupled receptors (GPCRs) have been produced in cell-free systems in high amounts and in functionally active forms.


Cell-free Protein Expression System (CFPS) - Mammal Cell-free Expression of Recombinant Proteins/Antibodies


Fig.1 Procedures of Mammal Cell-free Expression Systems


Unlike Bacteria Cell-free Expression System, Insect Cell-free Expression System and Wheat Germ Cell-free Expression System, mammalian-based cell-free protein systems derived from Rabbit Reticulocyte, HeLa, CHO offer a biochemical environment that is closely related to living human cells.

Mammalian-based cell-free protein systems offer a better acceptance of human genes as templates for the synthesis and correct folding of complex and multimeric human proteins. These proteins often require the formation of co- and post-translational modifications, such as glycosylation, phosphorylation and lipid modification, to achieve their appropriate conformation and thus their functional activity.


Fig.2 Features of Mammalian-based Cell Lysate Expression Systems


Advanced mammalian-based cell-free protein synthesis systems already contain endogenous microsomes derived from the endoplasmic reticulum of the cultured cells. These systems can be used for the synthesis of pharmaceutically relevant proteins, such as difficult-to-express proteins, post-translationally modified proteins and proteins with advanced biochemical properties.


Advanced Vector System:


Alpha Lifetech Inc. has created a powerful vector system to express human-like recombinant proteins, like double-polar proteins (membrane proteins) and other proteins required special modifications, case by case. We have pre-made vectors which combined the intergenic region (IGR) of the cricket paralysis virus (CrPV) and the encephalomyocarditis virus internal ribosomal entry site (IRES), named CrPV-IGR/IRES motif that shows to function efficiently in a broad range of eukaryotic cell lysates. And thus, we developed different mammalian-based cell lysates expression systems including a human K562-derived CFPS system, Hybridoma CFPS, Hela CFPS, CHO CFPS and HEK293F CFPS, according to different applications (Table 1).

Table 1 features of different mammalian-based cell-free expression systems.

 Table 1

Rabbit Reticulocyte CFPS

Hela Cell-Free CFPS






Protein Modification

Limited glycosylation

Moderated Glycosylation/Phosphorylation


Protein Integrity

Full/part length

Full/part length

Full/part length

Protein Activity

Native conformation




> 90%

> 95%

> 95%

Staff Background





Meanwhile, Alpha Lifetech Inc. can express recombinant proteins, especially membrane proteins, in a form of precipitation without detergents or a solubilized form in 24 detergents. (For more information, please feel free to contact us as soon as possible)