Table 1 Overview of recombinant proteins produces in the chloroplast of Chlamydomonas reinhardtii

VP1-CTB; Protein VP1 from foot and mouth disease virus (FMDV) fused to cholera toxin B (CTB)

3-4% Total Soluble Protein (TSP)

Demonstrated that the C. reinhardtii chloroplast derived VP1-CTB could bind to GM1-ganglioside receptor in vitro

(Sun et al. [2003])

HSV-lsc; Large single chain (lsc) antibody directed against glycoprotein D protein from Herpes simplex virus (HSV)

Not reported

First report to show that the C. reinhardtii chloroplast can efficiently fold antibodies and form disulfide bonds

(Mayfield et al. [2003])

TRAIL; Tumor necrosis factor-related apoptosis-inducing ligand

0.43%-0.67% TSP

(Yang et al. [2006])

M-SAA; Mammary-associated serum amyloid

3%-5% TSP

M-SAA was shown to generate mucin induction in a human intestinal epithelial cell line. Demonstrated that the psbA promoter yields high level or recombinant protein accumulation when the endogenous psbA gene is absent

(Manuell et al. [2007])

CSFV-E2; Classical swine fever virus (CSFV) structural protein E2

1.5-2% TSP

Subcutaneous immunization of mice with E2 was shown to induced IgG antibodies

(He et al. [2007])

Human glutamic acid decarboxylase (hGAD65)

0.25-0.3% TSP

The protein was shown to immunoreact with sera from diabetic mice

(Wang et al. [2008])

IBDV-VP2; Infectious burial disease virus VP2 protein

4-0.8% Total cell protein (TCP)

This report looked at the expression of 11 proteins. Nine proteins showed some level of accumulation, while the rest could not be detected. It showed that there are variations in the level of expression even amongst lines obtained with the transformation construct. Authors postulated the existence of the transformosome, a state in which particular genomic characteristics, induced incidentally with transformation, affect, negatively or positively, the expression of the transgene

(Surzycki et al. [2009])

IHNV-G; Infectious haematopoietic necrosis virus

< 0.5% TCP

IPNV-VP2; Infectious pancreatic necrosis virus

< 0.3% TCP

VP2 protein

1-0.1% TCP

IPNV-VP2 SBC; Infectious pancreatic necrosis virus

1-0.2% TCP

Quorum sensing-regulated gene (LecA) p57

< 0.5 TCP

PCV2; Porcine circovirus type 2

0.9-0.2% TCP

VP-2C

< 0.5% TCP

VP28

21-0.2% TCP

HC-83K7C; Heavy chain human monoclonal antibody against anthrax protective antigen 83 (PA83)

0.01% dwt

It was shown that the heavy and light chains expressed in trans could assembled into a fully-functional monoclonal antibody against PA83

(Tran et al. [2009])

LC-83K7C; Light chain human monoclonal antibody against anthrax PA83

CTB-D2; D2 fibronectin-binding domain of Staphylococcus aureus fused to the cholera toxin B subunit

0.7% TSP

First report to show that an orally-administered alga expressing an antigen in the chloroplast triggers a mucosal and systemic immune response in mice

(Dreesen et al. [2010])

14FN3; Domain 14 of human fibronectin

3%-0.15% TSP

This report looked at the expression of seven therapeutic proteins. For three of the proteins, a level of accumulation above 1% was observed, whereas for the rest of the proteins, erythropoietin, interferon β, and proinsulin no protein was detected. Biological activity was evaluated for VEGF and HMGB1

(Rasala et al. [2010])

VEGF; Human vascular endothelial growth factor

2%-0.1% TSP

HMGB1; High mobility group protein B1

2.5%-1% TSP

acrV2 and vapA2; antigens from the fish pathogen Aeromonas salmonicida

0.8% and 0.3% TP respectively

Showed that the psaA promoter-exon1 element can be used to drive the expression of foreign genes in non-photosynthetic strains

(Michelet et al. [2011])

Escherichia coli phytase gene ( appA )

N.D.

This study showed that algae expressing a bacterial phytase gene in the chloroplast could be lyophilized and administered orally to broiler chicks. The enzyme was active in the gut and reduce the fecal excretion of phytate.

(Yoon et al. [2011])

Pfs25 and Pfs28; surface proteins from Plasmodium falciparum

0.5% and 0.2% TSP respectively

First report to show that Pfs25 and Pfs28 can be produced without glycosilation and in a correct conformation recognized by monoclonal antibodies specific to conformational epitopes

(Gregory et al. [2012])

αCD22PE40; monomeric immunotoxin consisting on the single chain antibody that recognizes the CD22 surface protein from B-cells, fused to domains II and III of exotoxin A (PE40) from Pseudomonas aeruginosa

0.3%-0.4% TSP

First report to show that immunotoxins can be produced in an eukaryotic system without being toxic to the cell.

(Tran et al. [2013b])

αCD22HCH23PE40; dimeric version of αCD22PE40

0.2%-0.3% TSP

CtxB-Pfs25; Plasmodium falciparum surface protein 25 fused to the β subunit of the cholera toxin from Vibrio cholera

0.09% TSP

Demonstrated that the fusion protein can induced IgA antibodies when administered orally as part of a lyophilized powered. However, IgG antibodies could not be elicited with this route of administration

(Gregory et al. [2013])

αCD22Gel; single chain antibody targeting the CD22 receptor from B-cells, fused to the eukaryotic ribosome inactivating protein, gelonin, from Gelonium multiflorm

0.2%-0.3% TSP

Demonstrated that immunotoxin can efficiently bind to cancerous B-cells in vitro and kill them without affecting non B-cells

(Tran et al. [2013a])

αCD22CH23Gel; dimeric version of αCD22Gel

0.1% - 0.2% TSP