Antibody expressing pea seeds as fodder for prevention of gastrointestinal parasitic infections in chickens

<p>Abstract</p> <p>Background</p> <p>Coccidiosis caused by protozoans of genus <it>Eimeria </it>is a chicken parasitic disease of great economical importance. Conventional disease control strategies depend on vaccination and prophylactic use of anticoccidial drugs. Alternative solution to prevent and treat coccidiosis could be provided by passive immunization using orally delivered neutralizing antibodies. We investigated the possibility to mitigate the parasitic infection by feeding poultry with antibody expressing transgenic crop seeds.</p> <p>Results</p> <p>Using the phage display antibody library, we generated a panel of anti-<it>Eimeria </it>scFv antibody fragments with high sporozoite-neutralizing activity. These antibodies were expressed either transiently in agrobacteria-infiltrated tobacco leaves or stably in seeds of transgenic pea plants. Comparison of the scFv antibodies purified either from tobacco leaves or from the pea seeds demonstrated no difference in their antigen-binding activity and molecular form compositions. Force-feeding experiments demonstrated that oral delivery of flour prepared from the transgenic pea seeds had higher parasite neutralizing activity <it>in vivo </it>than the purified antibody fragments isolated from tobacco. The pea seed content was found to protect antibodies against degradation by gastrointestinal proteases (>100-fold gain in stability). <it>Ad libitum </it>feeding of chickens demonstrated that the transgenic seeds were well consumed and not shunned. Furthermore, feeding poultry with shred prepared from the antibody expressing pea seeds led to significant mitigation of infection caused both by high and low challenge doses of <it>Eimeria </it>oocysts.</p> <p>Conclusion</p> <p>The results suggest that our strategy offers a general approach to control parasitic infections in production animals using cost-effective antibody expression in crop seeds affordable for the animal health market.</p

Purification and immunodetection of the complete recombinant HER-2[neu] receptor produced in yeast

For the first time, the full length recombinant HER-2[neu] receptor has been produced in a yeast (Arxula adeninivorans). It is one of the most studied membrane receptors in oncology and is involved in aggressive tumor formation. A yeast integration rDNA cassette containing the human gene coding for the HER-2[neu] protein was constructed and a screening procedure was performed to select the most productive transformant. Different detergents were tested for efficient solubilization of the membrane bound protein, with CHAPS giving the best results. To increase the yield of the recombinant protein from HER-2[neu] producing A. adeninivorans, optimal culture parameters were established for cultivation in bioreactor. The recombinant protein was subsequently assayed using ELISA and SPR immunoassays systems with antibodies raised against two different epitopes of the human receptor. In both cases, elution fractions containing the recombinant HER-2[neu] receptor successfully reacted with the immunoassays with limits of quantification below 100 ng ml−1. These results demonstrate that the full length recombinant HER-2[neu] reported here has the potential to be a new standard for the detection of HER-2 type cancer

The complete genome of Blastobotrys (Arxula) adeninivorans LS3 - a yeast of biotechnological interest.

Background: The industrially important yeast Blastobotrys (Arxula) adeninivorans is an asexual hemiascomycete phylogenetically very distant from Saccharomyces cerevisiae. Its unusual metabolic flexibility allows it to use a wide range of carbon and nitrogen sources, while being thermotolerant, xerotolerant and osmotolerant./nResults: The sequencing of strain LS3 revealed that the nuclear genome of A. adeninivorans is 11.8 Mb long and consists of four chromosomes with regional centromeres. Its closest sequenced relative is Yarrowia lipolytica, although mean conservation of orthologs is low. With 914 introns within 6116 genes, A. adeninivorans is one of the most intron-rich hemiascomycetes sequenced to date. Several large species-specific families appear to result from multiple rounds of segmental duplications of tandem gene arrays, a novel mechanism not yet described in yeasts. An analysis of the genome and its transcriptome revealed enzymes with biotechnological potential, such as two extracellular tannases (Atan1p and Atan2p) of the tannic-acid catabolic route, and a new pathway for the assimilation of n-butanol via butyric aldehyde and butyric acid. Conclusions: The high-quality genome of this species that diverged early in Saccharomycotina will allow further fundamental studies on comparative genomics, evolution and phylogenetics. Protein components of different pathways for carbon and nitrogen source utilization were identified, which so far has remained unexplored in yeast, offering clues for further biotechnological developments. In the course of identifying alternative microorganisms for biotechnological interest, A. adeninivorans has already proved its strengthened competitiveness as a promising cell factory for many more applications.This work was supported in part by funding from the Consortium National de Recherche en Génomique (CNRG) to Génoscope, from CNRS (GDR 2354, Génolevures), ANR (ANR-05-BLAN-0331, GENARISE). The computing framework was supported by the funding of the University of Bordeaux 1, the Aquitaine Région in the program “Génotypage et Génomique Comparée”, the ACI IMPBIO “Génolevures En Ligne” and INRIA. We thank the System and Network Administration team in LaBRI for excellent help and advice. J.A.C. is supported by the PhD Program in Computational Biology of the Instituto Gulbenkian de Ciência, Portugal (sponsored by Fundação Calouste Gulbenkian, Siemens SA, and Fundação para a Ciência e Tecnologia; SFRH/BD/33528/2008). M.C. research was supported by a grant of the Deutscher Akademischer Austauschdienst (DAAD). T.G. research was partly supported by a grant from the Spanish Ministry of Economy and Competitiveness (BIO2012-37161). B.D. is a member of Institut Universitaire de Franc