Expression of Bioactive Thymosin Alpha 1 (Tα1) in Marker-free Transgenic Lettuce (Lactuca sativa)

Abstract

Thymosin α1 (Tα1) was widely used for the treatment of hepatitis (B and C) and several cancers. However, current production of Tα1 is difficultly meeting clinical needs. To develop a novel and safety approach for Tα1 production, we synthesized a Tα1 gene (124 bp) based on the plant codon usage bias and constructed a four-copy Tα1 gene concatemer (408 bp) by using isocaudamer technique. This 4×Tα1 structure was cloned into plant binary expression vector pCAMBIA2300 with twin transfer deoxyribonucleic acids (T-DNAs) and integrated into lettuce genome via Agrobacterium-mediated transformation. Thirteen positive plants were identified by polymerase chain reaction and confirmed by Southern blot analysis, and 11 marker-free lettuce plants were obtained in T2 generation. The content of recombined Tα1 (rTα1) protein reached 1798.317 ± 87.312 ng/g in fresh leaves of transgenic lettuce. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay demonstrated that rTα1 protein stimulated mouse splenic lymphocyte proliferation in vitro. These data suggest that biologically active rTα1 was successfully expressed in marker-free transgenic lettuce, and this method could provide an alternative choice for large-scale production of Tα1 in the future.

Antiviral Potential of Plants against COVID-19 during Outbreaks—An Update

“…Moreover, a synthetic pentapeptide such as thymopentin interacting with the active site in thymopoietin has been found to boost the production of antibodies for hepatitis B vaccines [ 127 ]. Plant bioreactors have been successfully applied to the production of thymosin-α-1 [ 128 , 129 ].…”

Expression and functional validation of heat-labile enterotoxin B (LTB) and cholera toxin B (CTB) subunits in transgenic rice (Oryza sativa)

“…Similarly, mammalian cell cultures are expensive, hindering production of large quantities of vaccines. The development of various plant expression systems has enabled the expression of foreign antigens in plant tissue as edible vaccine vehicles (Haq et al 1995 ; Du et al 2005 ; El Adab et al 2007 ; Ko et al 2009 ; Sim et al 2009 ; Unni and Soniya 2010 ; Cui et al 2011 ; Guo et al 2012 ). Plant-based edible vaccines offer advantages of longer shelf-life, stability at room temperature without loss of immunogenicity, and reduced production costs (Streatfield et al 2001 ).…”

Expression of the Human Tissue-Plasminogen Activator in Hairy Roots of Oriental Melon (Cucumis melo)

“…Many therapeutic proteins, valuable secondary metabolites and functional recombinant proteins have been produced using hairy roots cultures or transgenic plants, such as thymosin alpha 1 (Cui et al 2010), human secreted alkaline phosphatase (Gaume et al 2003), fibrinolytic enzyme ), elevated ginsenoside (Liang et al 2009), cry1Ac (Nandeshwar et al 2009), monoclonal antibodies (Sharp and Doran 2001), synthetic heat-labile enterotoxin B subunit and hemagglutinin-neuraminidaseneutralizing epitope fusion protein ), ribosome-inactivating proteins (Thorup et al 1994), human acetylcholinesterase (Woods et al 2008), hepatitis B surface antigen (Unni and Soniya 2010), and human granulocyte-macrophage colony stimulating factor (Wang et al 2009). These studies demonstrate that hairy roots and transgenic plants can be a better alternative to mammalian cell cultures and microbial fermentation for the production of recombinant proteins.…”