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Malinczak CA, Burns Naas LA, Clark A, Conze D, DiNovi M, Kaminski N, Kruger C, Lönnerdal B, Lukacs NW, Merker R, Peterson R. Workshop report: A study roadmap to evaluate the safety of recombinant human lactoferrin expressed in Komagataella phaffii intended as an ingredient in conventional foods - Recommendations of a scientific expert panel. Food Chem Toxicol 2024; 190:114817. [PMID: 38880466 DOI: 10.1016/j.fct.2024.114817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2024] [Revised: 06/03/2024] [Accepted: 06/12/2024] [Indexed: 06/18/2024]
Abstract
Human milk lactoferrin (hmLF) is a glycoprotein with well-known effects on immune function. Helaina Inc. has used a glycoengineered yeast, Komatagaella phaffii, to produce recombinant human lactoferrin (Helaina rhLF, Effera™) that is structurally similar to hmLF with intended uses as a food ingredient. However, earlier FDA reviews of rhLF were withdrawn due to insufficient safety data and unanswered safety questions the experts and FDA raised about the immunogenicity/immunotoxicity risks of orally ingested rhLF. Helaina organized a panel of leading scientists to build and vet a safety study roadmap containing the studies and safety endpoints needed to address these questions. Panelists participated in a one-day virtual workshop in June 2023 and ensuing discussions through July 2023. Relevant workshop topics included physicochemical properties of LF, regulatory history of bovine LF and rhLF as food ingredients in the FDA's generally recognized as safe (GRAS) program, and synopses of publicly available studies on the immunogenicity/alloimmunization, immunotoxicology, iron homeostasis, and absorption, distribution, metabolism, and excretion of rhLF. Panelists concluded that the safety study roadmap addresses the unanswered safety questions and the intended safe use of rhLF as a food ingredient for adults and agreed on broad applications of the roadmap to assess the safety and support GRAS of other recombinant milk proteins with immunomodulatory functions.
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Affiliation(s)
| | | | | | | | | | - Norbert Kaminski
- Department of Pharmacology & Toxicology, Institute for Integrative Toxicology, Michigan State University, East Lansing, MI, USA.
| | | | - Bo Lönnerdal
- Department of Internal Medicine, University of California, Davis, CA, USA.
| | - Nicholas W Lukacs
- Mary H. Weiser Food Allergy Center, University of Michigan, Ann Arbor, MI, USA.
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2
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Anaya Y, Rosario Martinez R, Goodman RE, Johnson P, Vajpeyi S, Lu X, Peterson R, Weyers SM, Breen B, Newsham K, Scottoline B, Clark AJ, Malinczak CA. Evaluation of the potential food allergy risks of human lactoferrin expressed in Komagataella phaffii. Front Immunol 2024; 15:1380028. [PMID: 39114650 PMCID: PMC11303282 DOI: 10.3389/fimmu.2024.1380028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 07/03/2024] [Indexed: 08/10/2024] Open
Abstract
Introduction Prior to the introduction of novel food ingredients into the food supply, safety risk assessments are required, and numerous prediction models have been developed and validated to evaluate safety. Methods The allergenic risk potential of Helaina recombinant human lactoferrin (rhLF, Effera™), produced in Komagataella phaffii (K. phaffii) was assessed by literature search, bioinformatics sequence comparisons to known allergens, glycan allergenicity assessment, and a simulated pepsin digestion model. Results The literature search identified no allergenic risk for Helaina rhLF, K. phaffii, or its glycans. Bioinformatics search strategies showed no significant risk for cross-reactivity or allergenicity between rhLF or the 36 residual host proteins and known human allergens. Helaina rhLF was also rapidly digested in simulated gastric fluid and its digestibility profile was comparable to human milk lactoferrin (hmLF), further demonstrating a low allergenic risk and similarity to the hmLF protein. Conclusion Collectively, these results demonstrate a low allergenic risk potential of Helaina rhLF and do not indicate the need for further clinical testing or serum IgE binding to evaluate Helaina rhLF for risk of food allergy prior to introduction into the food supply.
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Affiliation(s)
- Yanisa Anaya
- Nutritional Biology & Safety, Helaina, Inc, New York, NY, United States
| | | | | | - Philip Johnson
- University of Nebraska-Lincoln, Lincoln, NE, United States
| | | | - Xiaoning Lu
- Nutritional Biology & Safety, Helaina, Inc, New York, NY, United States
| | - Ross Peterson
- Regulatory Affairs, Helaina, Inc, New York, NY, United States
| | | | - Bella Breen
- Late Stage R&D, Helaina, Inc, New York, NY, United States
| | - Kahler Newsham
- Late Stage R&D, Helaina, Inc, New York, NY, United States
| | - Brian Scottoline
- Department of Pediatrics, Oregon Health & Science University, Portland, OR, United States
| | - Anthony J. Clark
- Late Stage R&D, Helaina, Inc, New York, NY, United States
- Regulatory Affairs, Helaina, Inc, New York, NY, United States
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3
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Murbach TS, Glávits R, Jayasena S, Moghadam Maragheh N, Endres JR, Hirka G, Goodman RE, Vértesi A, Béres E, Pasics Szakonyiné I. Toxicology and digestibility of Chlamydomonas debaryana green algal biomass. J Appl Toxicol 2023. [PMID: 36680512 DOI: 10.1002/jat.4438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 12/29/2022] [Accepted: 01/17/2023] [Indexed: 01/22/2023]
Abstract
There is an economic interest, both for food security and for the non-meat-eating population, in the development of novel, sustainable sources of high-quality protein. The green algae Chlamydomonas reinhardtii has already been developed for this purpose, and the closely related species, Chlamydomonas debaryana, is a complementary source that also presents some additional advantages, such as reduced production cost. To determine whether C. debaryana may have a similar safety profile to that of C. reinhardtii, a wild type strain was obtained, designated TS04 after confirmation of its identity, and subjected to a battery of preclinical studies. Genetic toxicity was evaluated using a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and an in vivo mammalian micronucleus test in a mouse model. No genotoxic potential (e.g., mutagenicity and clastogenicity) was observed in these tests under the employed conditions up to maximum recommended concentrations or doses. To assess general toxicity, a 90-day repeated-dose oral toxicity study was conducted in rats. No mortality or adverse effects were observed, and no target organs were identified up to the maximum feasible dose, due to solubility, of 4,000 mg/kg bw/day. The no-observed-adverse-effect level was determined as the highest dose tested. A digestibility study in simulated gastric fluid was conducted and determined that TS04 has low allergenic potential, exhibiting rapid digestion of proteins. Due to the negative results of our evaluation, it is reasonable to proceed with further development and additional investigations to contribute towards a safety assessment of the proposed use in food for human consumption.
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Affiliation(s)
| | | | - Shyamali Jayasena
- Food Allergy Research and Resource Program (FARRP), Department of Food Science and Technology, University of Nebraska, Lincoln, Nebraska, USA
| | - Niloofar Moghadam Maragheh
- Food Allergy Research and Resource Program (FARRP), Department of Food Science and Technology, University of Nebraska, Lincoln, Nebraska, USA
| | | | - Gábor Hirka
- Toxi-Coop Zrt., Budapest, Hungary.,Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
| | - Richard E Goodman
- Food Allergy Research and Resource Program (FARRP), Department of Food Science and Technology, University of Nebraska, Lincoln, Nebraska, USA
| | - Adél Vértesi
- Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
| | - Erzsébet Béres
- Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
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4
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Comparative digestion of thermally treated vertebrates and invertebrates allergen pairs in real food matrix. Food Chem 2022; 405:134981. [DOI: 10.1016/j.foodchem.2022.134981] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 10/28/2022] [Accepted: 11/14/2022] [Indexed: 11/22/2022]
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5
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Herman RA, Zhang JXQ. Simulated gastric fluid assay for estimating the digestibility of newly expressed proteins in GE crops: Missteps in development and interpretation. Food Chem Toxicol 2022; 169:113436. [PMID: 36165819 DOI: 10.1016/j.fct.2022.113436] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 09/09/2022] [Accepted: 09/14/2022] [Indexed: 11/28/2022]
Abstract
Digestive stability of a food protein in simulated gastric fluid (SGF) continues to be considered a risk factor for allergy, even though the current science does not support this belief. Methodological shortcomings of the adaption of the SGF assay for use with purified proteins has been cited as a reason to discount results that do not conform to this belief. Missteps in conducting and interpreting the results of SGF assays are reviewed here. However, these methodological shortcomings do not invalidate the conclusion that allergenic proteins are not systematically more stable to digestion than non-allergens. The growing evidence for the dual allergen exposure hypothesis, whereby sensitization to food allergens is primarily caused by dermal and inhalation exposure to food dust, and tolerization against food allergy is primarily induced by gut exposure in food, likely explains why the digestive stability of a protein is not a risk factor for allergenicity.
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Affiliation(s)
- Rod A Herman
- Corteva Agriscience, Regulatory and Stewardship, Indianapolis, IN, 46268, USA.
| | - John X Q Zhang
- Corteva Agriscience, Regulatory and Stewardship, Johnston, IA, USA
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6
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Wang C, Bean GJ, Chen CJ, Kessenich CR, Peng J, Visconti NR, Milligan JS, Moore RG, Tan J, Edrington TC, Li B, Giddings KS, Bowen D, Luo J, Ciche T, Moar WJ. Safety assessment of Mpp75Aa1.1, a new ETX_MTX2 protein from Brevibacillus laterosporus that controls western corn rootworm. PLoS One 2022; 17:e0274204. [PMID: 36074780 PMCID: PMC9455866 DOI: 10.1371/journal.pone.0274204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 08/23/2022] [Indexed: 11/24/2022] Open
Abstract
The recently discovered insecticidal protein Mpp75Aa1.1 from Brevibacillus laterosporus is a member of the ETX_MTX family of beta-pore forming proteins (β-PFPs) expressed in genetically modified (GM) maize to control western corn rootworm (WCR; Diabrotica virgifera virgifera LeConte). In this manuscript, bioinformatic analysis establishes that although Mpp75Aa1.1 shares varying degrees of similarity to members of the ETX_MTX2 protein family, it is unlikely to have any allergenic, toxic, or otherwise adverse biological effects. The safety of Mpp75Aa1.1 is further supported by a weight of evidence approach including evaluation of the history of safe use (HOSU) of ETX_MTX2 proteins and Breviballus laterosporus. Comparisons between purified Mpp75Aa1.1 protein and a poly-histidine-tagged (His-tagged) variant of the Mpp75Aa1.1 protein demonstrate that both forms of the protein are heat labile at temperatures at or above 55°C, degraded by gastrointestinal proteases within 0.5 min, and have no adverse effects in acute mouse oral toxicity studies at a dose level of 1920 or 2120 mg/kg body weight. These results support the use of His-tagged proteins as suitable surrogates for assessing the safety of their non-tagged parent proteins. Taken together, we report that Mpp75Aa1.1 is the first ETX-MTX2 insecticidal protein from B. laterosporus and displays a similar safety profile as typical Cry proteins from Bacillus thuringiensis.
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Affiliation(s)
- Cunxi Wang
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Gregory J. Bean
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Chun Ju Chen
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | | | - Jiexin Peng
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | | | - Jason S. Milligan
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Robert G. Moore
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Jianguo Tan
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | | | - Bin Li
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Kara S. Giddings
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - David Bowen
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Jinhua Luo
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - Todd Ciche
- Bayer Crop Science, Chesterfield, Missouri, United States of America
| | - William J. Moar
- Bayer Crop Science, Chesterfield, Missouri, United States of America
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7
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Assessing protein digestibility in allergenicity risk assessment: A comparison of in silico and high throughput in vitro gastric digestion assays. Food Chem Toxicol 2022; 167:113273. [PMID: 35809717 DOI: 10.1016/j.fct.2022.113273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2022] [Revised: 06/26/2022] [Accepted: 07/01/2022] [Indexed: 10/17/2022]
Abstract
The susceptibility of a novel food protein to digestion in the pepsin resistance test is widely used to inform the allergenicity risk assessment process. However, it does not model the variation in the intragastric environment found in vivo. Consequently a 96-well plate format in vitro gastric digestion protocol has been developed with a high and low pepsin activity test executed at pH 1.2, 2.5, 5.5 and 6.5. It was used to analyse seven allergens (from milk, egg, peach and peanut) and two non-allergens (cytochrome c and zein). Digestion was monitored using SDS-PAGE and densitometry. In silico predictions were not confirmed experimentally for most of the proteins studied. Proteins were ranked according to half-life and showed susceptibility to digestion was related to the stability of protein structure and protein solubility rather than allergenicity per se. Highly digestible proteins, such as β-casein and Ara h 1, generated abundant resistant fragments Mr > 3.5 kDa in the low pepsin activity test which could be immunologically significant within the context of allergenicity risk assessment for susceptible groups such as infants. The high- and low pepsin activity tests used in this study provided complementary data to support allergenicity risk assessment and used only 10 mg protein.
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8
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Akkerdaas JH, Cianferoni A, Islamovic E, Kough J, Ladics GS, McClain S, Poulsen LK, Silvanovich A, Pereira Mouriès L, van Ree R. Impact of Food Matrices on Digestibility of Allergens and Poorly Allergenic Homologs. FRONTIERS IN ALLERGY 2022; 3:909410. [PMID: 35769559 PMCID: PMC9234860 DOI: 10.3389/falgy.2022.909410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 05/04/2022] [Indexed: 11/13/2022] Open
Abstract
Background Protease resistance is considered a risk factor for allergenicity of proteins, although the correlation is low. It is nonetheless a part of the weight-of-evidence approach, proposed by Codex, for assessing the allergenicity risk of novel food proteins. Susceptibility of proteins to pepsin is commonly tested with purified protein in solution. Objective Food proteins are rarely consumed in purified form. Our aim was to evaluate the impact of experimental and endogenous food matrices on protease susceptibility of homologous protein pairs with different degrees of allergenicity. Methods Porcine and shrimp tropomyosin (ST) were subjected to sequential exposure to amylase, pepsin, and pancreatin in their respective endogenous matrix (pork tenderloin/boiled shrimp) and in three different experimental matrices (dessert mousse [DM], soy milk [SM], and chocolate bar [CB]). Digestion was monitored by immunoblotting using tropomyosin-specific antibodies. Recombinant peach and strawberry lipid transfer protein were biotinylated, spiked into both peach and strawberry fruit pulp, and subjected to the same sequential digestion protocol. Digestion was monitored by immunoblotting using streptavidin for detection. Results Chocolate bar, and to a lesser extent SM, had a clear protective effect against pepsin digestion of porcine tropomyosin (PT) and to a lesser extent of ST. Increased resistance was associated with increased protein content. Spiking experiments with bovine serum albumin (BSA) confirmed the protective effect of a protein-rich matrix. The two tropomyosins were both highly resistant to pepsin in their protein-rich and lean native food matrix. Pancreatin digestion remained rapid and complete, independent of the matrix. The fat-rich environment did not transfer protection against pepsin digestion. Spiking of recombinant peach and strawberry lipid transfer proteins into peach and strawberry pulp did not reveal any differential protective effect that could explain differences in allergenicity of both fruits. Conclusions Protein-rich food matrices delay pepsin digestion by saturating the protease. This effect is most apparent for proteins that are highly pepsin susceptible in solution. The inclusion of food matrices does not help in understanding why some proteins are strong primary sensitizers while homologs are very poor allergens. Although for induction of symptoms in food allergic patients (elicitation), a protein-rich food matrix that may contribute to increased risk, our results indicate that the inclusion of food matrices in the weight-of-evidence approach for estimating the potential risks of novel proteins to become allergens (sensitization), is most likely of very limited value.
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Affiliation(s)
- J. H. Akkerdaas
- Department of Experimental Immunology, Amsterdam University Medical Centers, Amsterdam, Netherlands
| | - A. Cianferoni
- Children's Hospital of Philadelphia, Philadelphia, PA, United States
| | - E. Islamovic
- BASF Corporation, Morrisville, NC, United States
| | - J. Kough
- US EPA, Washington, DC, United States
| | - G. S. Ladics
- Dupont Nutrition and Biosciences, IFF, Wilmington, DE, United States
| | - S. McClain
- Syngenta Crop Protection, LLC, Greensboro, NC, United States
| | - L. K. Poulsen
- Copenhagen University Hospital at Gentofte, Copenhagen, Denmark
| | - A. Silvanovich
- Bayer U.S. Crop Science, Chesterfield, MO, United States
| | - L. Pereira Mouriès
- Health & Environmental Sciences Institute (HESI), Washington, DC, United States
| | - R. van Ree
- Department of Experimental Immunology, Amsterdam University Medical Centers, Amsterdam, Netherlands
- Department of Otorhinolaryngology, Amsterdam University Medical Centers, Amsterdam, Netherlands
- *Correspondence: R. van Ree
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9
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Analysis of the Factors Affecting Static In Vitro Pepsinolysis of Food Proteins. Molecules 2022; 27:molecules27041260. [PMID: 35209049 PMCID: PMC8878058 DOI: 10.3390/molecules27041260] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 02/08/2022] [Accepted: 02/10/2022] [Indexed: 02/04/2023] Open
Abstract
In this meta-analysis, we collected 58 publications spanning the last seven decades that reported static in vitro protein gastric digestion results. A number of descriptors of the pepsinolysis process were extracted, including protein type; pepsin activity and concentration; protein concentration; pH; additives; protein form (e.g., ‘native’, ‘emulsion’, ‘gel’, etc.); molecular weight of the protein; treatment; temperature; and half-times (HT) of protein digestion. After careful analysis and the application of statistical techniques and regression models, several general conclusions could be extracted from the data. The protein form to digest the fastest was ‘emulsion’. The rate of pepsinolysis in the emulsion was largely independent of the protein type, whereas the gastric digestion of the native protein in the solution was strongly dependent on the protein type. The pepsinolysis was shown to be strongly dependent on the structural components of the proteins digested—specifically, β-sheet-inhibited and amino acid, leucine, methionine, and proline-promoted digestion. Interestingly, we found that additives included in the digestion mix to alter protein hydrolysis had, in general, a negligible effect in comparison to the clear importance of the protein form or additional treatment. Overall, the findings allowed for the targeted creation of foods for fast or slow protein digestion, depending on the nutritional needs.
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10
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Murbach TS, Glávits R, Maragheh NM, Endres JR, Hirka G, Goodman RE, Lu G, Vértesi A, Béres E, Szakonyiné IP. Evaluation of the genotoxic potential of protoporphyrin IX and the safety of a protoporphyrin IX-rich algal biomass. J Appl Toxicol 2022; 42:1253-1275. [PMID: 35104912 DOI: 10.1002/jat.4293] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 01/18/2022] [Accepted: 01/26/2022] [Indexed: 11/06/2022]
Abstract
Chlamydomonas reinhardtii is a nonpathogenic, nontoxigenic green algae used as a sustainable source of protein in foods. In order to mimic meat-like qualities, a strain rich in protoporphyrin IX (PPIX), an endogenous heme/chlorophyll precursor, was developed using an evolution and selection strategy, and investigations were carried out to evaluate the safety of the novel strain, C. reinhardtii (red), strain TAI114 (TAI114). Digestibly and proteomic evaluations were conducted to determine whether any potentially allergenic or toxic proteins occurred as the result of the mutation process. The genotoxic potential of pure PPIX was evaluated using a bacterial reverse mutation test, an in vitro mammalian chromosomal aberration test, and an in vivo mammalian micronucleus test. Finally, the novel TAI114 biomass was evaluated for general toxicity and identification of target organs in a 90-day repeated-dose oral toxicity study in rats. All proteins were rapidly degraded in pepsin at pH 2.0 suggesting low allergenic potential. The proteomic evaluation indicated that TAI114 biomass contains typical C. reinhardtii proteins. PPIX was unequivocally negative for genotoxic potential and no target organs or adverse effects were observed in rats up to the maximum feasible dose of 4000 mg/kg bw/day TAI114 biomass, which was determined to be the no-observed-adverse-effect-level (NOAEL). These results support the further development and risk characterization of TAI114 biomass as a novel ingredient for use in the meat analogue category of food.
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Affiliation(s)
- Timothy S Murbach
- AIBMR Life Sciences, Inc., 1425 Broadway, Suite 458, Seattle, WA, USA
| | - Róbert Glávits
- Toxi-Coop Zrt., Berlini utca 47-49, H-1045, Budapest, Hungary
| | - Niloofar Moghadam Maragheh
- Goodman Laboratory, Food Allergy Research and Resource Program (FARRP), University of Nebraska, Dept. of Food Science & Technology, Lincoln, NE, USA
| | - John R Endres
- AIBMR Life Sciences, Inc., 1425 Broadway, Suite 458, Seattle, WA, USA
| | - Gábor Hirka
- Toxi-Coop Zrt., Berlini utca 47-49, H-1045, Budapest, Hungary.,Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
| | - Richard E Goodman
- Goodman Laboratory, Food Allergy Research and Resource Program (FARRP), University of Nebraska, Dept. of Food Science & Technology, Lincoln, NE, USA
| | - Guihua Lu
- Triton Algae Innovations, 11760 Sorrento Valley Road, Suite R, San Diego, California, USA
| | - Adél Vértesi
- Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
| | - Erzsébet Béres
- Toxi-Coop Zrt., Arácsi út 97, 8230, Balatonfüred, Hungary
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11
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Mullins E, Bresson J, Dalmay T, Dewhurst IC, Epstein MM, George Firbank L, Guerche P, Hejatko J, Naegeli H, Nogué F, Rostoks N, Sánchez Serrano JJ, Savoini G, Veromann E, Veronesi F, Fernandez Dumont A, Moreno FJ. Scientific Opinion on development needs for the allergenicity and protein safety assessment of food and feed products derived from biotechnology. EFSA J 2022; 20:e07044. [PMID: 35106091 PMCID: PMC8787593 DOI: 10.2903/j.efsa.2022.7044] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
This Scientific Opinion addresses the formulation of specific development needs, including research requirements for allergenicity assessment and protein safety, in general, which is urgently needed in a world that demands more sustainable food systems. Current allergenicity risk assessment strategies are based on the principles and guidelines of the Codex Alimentarius for the safety assessment of foods derived from 'modern' biotechnology initially published in 2003. The core approach for the safety assessment is based on a 'weight-of-evidence' approach because no single piece of information or experimental method provides sufficient evidence to predict allergenicity. Although the Codex Alimentarius and EFSA guidance documents successfully addressed allergenicity assessments of single/stacked event GM applications, experience gained and new developments in the field call for a modernisation of some key elements of the risk assessment. These should include the consideration of clinical relevance, route of exposure and potential threshold values of food allergens, the update of in silico tools used with more targeted databases and better integration and standardisation of test materials and in vitro/in vivo protocols. Furthermore, more complex future products will likely challenge the overall practical implementation of current guidelines, which were mainly targeted to assess a few newly expressed proteins. Therefore, it is timely to review and clarify the main purpose of the allergenicity risk assessment and the vital role it plays in protecting consumers' health. A roadmap to (re)define the allergenicity safety objectives and risk assessment needs will be required to inform a series of key questions for risk assessors and risk managers such as 'what is the purpose of the allergenicity risk assessment?' or 'what level of confidence is necessary for the predictions?'.
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12
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Yigit S, Hallaj NS, Sugarman JL, Chong LC, Roman SE, Abu-Taleb LM, Goodman RE, Johnson PE, Behrens AM. Toxicological assessment and food allergy of silk fibroin derived from Bombyx mori cocoons. Food Chem Toxicol 2021; 151:112117. [DOI: 10.1016/j.fct.2021.112117] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 03/05/2021] [Accepted: 03/08/2021] [Indexed: 12/21/2022]
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13
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Assessment of the potential allergenicity and toxicity of Pichia proteins in a novel leghemoglobin preparation. Regul Toxicol Pharmacol 2021; 119:104817. [DOI: 10.1016/j.yrtph.2020.104817] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 10/16/2020] [Accepted: 10/30/2020] [Indexed: 01/03/2023]
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14
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Naegeli H, Bresson J, Dalmay T, Dewhurst IC, Epstein MM, Firbank LG, Guerche P, Hejatko J, Moreno FJ, Mullins E, Nogué F, Rostoks N, Sánchez Serrano JJ, Savoini G, Veromann E, Veronesi F, Dumont AF. Statement on in vitro protein digestibility tests in allergenicity and protein safety assessment of genetically modified plants. EFSA J 2021; 19:e06350. [PMID: 33473251 PMCID: PMC7801955 DOI: 10.2903/j.efsa.2021.6350] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
This statement supplements and updates the GMO Panel guidance document on allergenicity of genetically modified (GM) plants published in 2017. In that guidance document, the GMO Panel considered that additional investigations on in vitro protein digestibility were needed before providing any additional recommendations in the form of guidance to applicants. Thus, an interim phase was proposed to assess the utility of an enhanced in vitro digestion test, as compared to the classical pepsin resistance test. Historically, resistance to degradation by pepsin using the classical pepsin resistance test has been considered as additional information, in a weight-of-evidence approach, for the assessment of allergenicity and toxicity of newly expressed proteins in GM plants. However, more recent evidence does not support this test as a good predictor of allergenic potential for hazard. Furthermore, there is a need for more reliable systems to predict the fate of the proteins in the gastrointestinal tract and how they interact with the relevant human cells. Nevertheless, the classical pepsin resistance test can still provide some information on the physicochemical properties of novel proteins relating to their stability under acidic conditions. But other methods can be used to obtain data on protein's structural and/or functional integrity. It is acknowledged that the classical pepsin resistance test is embedded into international guidelines, e.g. Codex Alimentarius and Regulation (EU) No 503/2013. For future development, a deeper understanding of protein digestion in the gastrointestinal tract could enable the framing of more robust strategies for the safety assessment of proteins. Given the high complexity of the digestion and absorption process of dietary proteins, it is needed to clarify and identify the aspects that could be relevant to assess potential risks of allergenicity and toxicity of proteins. To this end, a series of research questions to be addressed are also formulated in this statement.
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15
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Comparison of digestibility and potential allergenicity of raw shrimp (Litopenaeus vannamei) extracts in static and dynamic digestion systems. Food Chem 2020; 345:128831. [PMID: 33326890 DOI: 10.1016/j.foodchem.2020.128831] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 11/10/2020] [Accepted: 12/03/2020] [Indexed: 11/23/2022]
Abstract
In this work, a simplified dynamic digestion system was developed, and used for comparing the digestibility and potential allergenicity of raw shrimp extracts (RSE) in static and dynamic digestion systems. Protein hydrolysis was analyzed by electrophoresis, and the potential allergenicity was reflected in IgG/IgE binding ability and activation of basophils. In comparison with static digestion, protein hydrolysis indicated different kinetic behaviors, especially tropomyosin (TM) showed better digestion stability during dynamic digestion. The potential allergenicity of RSE exhibited different changing trends with digestion in the two systems. However, the apparent molecular weight (Mw) of immune fragments (>11 kDa) showed good approximation, and the IgE-binding fragment near 70 kDa revealed outstanding digestion stability than primordial protein in both systems. In conclusion, the dynamic conditions had a significant impact on the assessment of the persistence and potential allergenicity of digestion-resistant allergens, while the apparent Mw of IgG/IgE binding hydrolysate was not affected.
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16
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Niaz B, Saeed F, Ahmed A, Imran M, Maan AA, Khan MKI, Tufail T, Anjum FM, Hussain S, Suleria HAR. Lactoferrin (LF): a natural antimicrobial protein. INTERNATIONAL JOURNAL OF FOOD PROPERTIES 2019. [DOI: 10.1080/10942912.2019.1666137] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Bushra Niaz
- Institute of Home & Food Sciences, Government College University, Faisalabad, Pakistan
| | - Farhan Saeed
- Institute of Home & Food Sciences, Government College University, Faisalabad, Pakistan
| | - Awais Ahmed
- Institute of Home & Food Sciences, Government College University, Faisalabad, Pakistan
| | - Muhammad Imran
- Faculty of Allied Health Sciences, University Institute of Diet & Nutritional Sciences, University of Lahore, Lahore, Pakistan
| | - Abid Aslam Maan
- National Institute of Food Science and Technology, University of Agriculture, Faisalabad, Pakistan
| | | | - Tabussam Tufail
- Institute of Home & Food Sciences, Government College University, Faisalabad, Pakistan
| | | | - Shahzad Hussain
- College of Food and Agricultural Sciences, King Saud, University, Riyadh, Saudi Arabia
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17
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Ladics GS. Assessment of the potential allergenicity of genetically-engineered food crops. J Immunotoxicol 2018; 16:43-53. [PMID: 30409058 DOI: 10.1080/1547691x.2018.1533904] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
An extensive safety assessment process exists for genetically-engineered (GE) crops. The assessment includes an evaluation of the introduced protein as well as the crop containing the protein with the goal of demonstrating the GE crop is "as-safe-as" non-GE crops in the food supply. One of the evaluations for GE crops is to assess the expressed protein for allergenic potential. Currently, no single factor is recognized as a predictor for protein allergenicity. Therefore, a weight-of-the-evidence approach, which accounts for a variety of factors and approaches for an overall assessment of allergenic potential, is conducted. This assessment includes an evaluation of the history of exposure and safety of the gene(s) source; protein structure (e.g. amino acid sequence identity to human allergens); stability of the protein to pepsin digestion in vitro; heat stability of the protein; glycosylation status; and when appropriate, specific IgE binding studies with sera from relevant clinically allergic subjects. Since GE crops were first commercialized over 20 years ago, there is no proof that the introduced novel protein(s) in any commercialized GE food crop has caused food allergy.
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18
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Spiric J, Koppelman SJ, Knulst A, Nordlee JA, Taylor SL, Baumert JL. In vitro
digestion and characterisation of 2S albumin and digestion-resistant peptides in pecan. Int J Food Sci Technol 2018. [DOI: 10.1111/ijfs.13739] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jelena Spiric
- Food Allergy Research and Resource Program; Department of Food Science and Technology; University of Nebraska; Lincoln NE 68588-6207 USA
- Division of Allergology; Paul-Ehrlich-Institut; 63225 Langen Germany
| | - Stef J. Koppelman
- Food Allergy Research and Resource Program; Department of Food Science and Technology; University of Nebraska; Lincoln NE 68588-6207 USA
| | - Andre Knulst
- Department of Dermatology/Allergology; UMC Utrecht; 3584 CX Utrecht The Netherlands
| | - Julie A. Nordlee
- Food Allergy Research and Resource Program; Department of Food Science and Technology; University of Nebraska; Lincoln NE 68588-6207 USA
| | - Steve L. Taylor
- Food Allergy Research and Resource Program; Department of Food Science and Technology; University of Nebraska; Lincoln NE 68588-6207 USA
| | - Joseph L. Baumert
- Food Allergy Research and Resource Program; Department of Food Science and Technology; University of Nebraska; Lincoln NE 68588-6207 USA
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19
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Jin Y, He X, Andoh‐Kumi K, Fraser RZ, Lu M, Goodman RE. Evaluating Potential Risks of Food Allergy and Toxicity of Soy Leghemoglobin Expressed in Pichia pastoris. Mol Nutr Food Res 2018; 62:1700297. [PMID: 28921896 PMCID: PMC5813221 DOI: 10.1002/mnfr.201700297] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Revised: 08/09/2017] [Indexed: 11/24/2022]
Abstract
SCOPE The Soybean (Glycine max) leghemoglobin c2 (LegHb) gene was introduced into Pichia pastoris yeast for sustainable production of a heme-carrying protein, for organoleptic use in plant-based meat. The potential allergenicity and toxicity of LegHb and 17 Pichia host-proteins each representing ≥1% of total protein in production batches are evaluated by literature review, bioinformatics sequence comparisons to known allergens or toxins, and in vitro pepsin digestion. METHODS AND RESULTS Literature searches found no evidence of allergenicity or toxicity for these proteins. There are no significant sequence matches of LegHb to known allergens or toxins. Eleven Pichia proteins have modest identity matches to minor environmental allergens and 13 Pichia proteins have significant matches to proteins from toxic sources. Yet the matched allergens and toxins have similar matches to proteins from the commonly consumed yeast Saccharomyces cerevisiae, without evidence of food allergy or toxicity. The demonstrated history of safe use indicates additional tests for allergenicity and toxicity are not needed. The LegHb and Pichia sp. proteins were rapidly digested by pepsin at pH 2. CONCLUSION These results demonstrate that foods containing recombinant soy LegHb produced in Pichia sp. are unlikely to present an unacceptable risk of allergenicity or toxicity to consumers.
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Affiliation(s)
- Yuan Jin
- Food Allergy Research and Resource ProgramDept. of Food Science & TechnologyUniversity of Nebraska‐LincolnLincolnNEUSA
| | - Xiaoyun He
- College of Food Science and Nutritional EngineeringChina Agricultural UniversityBeijingChina
| | - Kwame Andoh‐Kumi
- Food Allergy Research and Resource ProgramDept. of Food Science & TechnologyUniversity of Nebraska‐LincolnLincolnNEUSA
| | | | - Mei Lu
- Food Allergy Research and Resource ProgramDept. of Food Science & TechnologyUniversity of Nebraska‐LincolnLincolnNEUSA
| | - Richard E. Goodman
- Food Allergy Research and Resource ProgramDept. of Food Science & TechnologyUniversity of Nebraska‐LincolnLincolnNEUSA
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20
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Delaney B, Goodman RE, Ladics GS. Food and Feed Safety of Genetically Engineered Food Crops. Toxicol Sci 2017; 162:361-371. [DOI: 10.1093/toxsci/kfx249] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Affiliation(s)
- Bryan Delaney
- DuPont Pioneer, International, Inc, 8325 N 62nd Avenue, Johnston, IA 50131, USA
| | - Richard E Goodman
- Food Science & Technology, University of Nebraska, 1901 North 21St Street, Lincoln Nebraska, Lincoln, NE 68588, USA
| | - Gregory S Ladics
- DuPont Haskell Laboratory, 1090 Elkton Road, Newark, DE, 19711, USA
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21
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Incorporation of in vitro digestive enzymes in an intestinal epithelial cell line model for protein hazard identification. Toxicol In Vitro 2017; 44:85-93. [DOI: 10.1016/j.tiv.2017.06.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Revised: 06/04/2017] [Accepted: 06/17/2017] [Indexed: 11/18/2022]
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22
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Wang R, Edrington TC, Storrs SB, Crowley KS, Ward JM, Lee TC, Liu ZL, Li B, Glenn KC. Analyzing pepsin degradation assay conditions used for allergenicity assessments to ensure that pepsin susceptible and pepsin resistant dietary proteins are distinguishable. PLoS One 2017; 12:e0171926. [PMID: 28207780 PMCID: PMC5312868 DOI: 10.1371/journal.pone.0171926] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Accepted: 01/29/2017] [Indexed: 11/18/2022] Open
Abstract
The susceptibility of a dietary protein to proteolytic degradation by digestive enzymes, such as gastric pepsin, provides information on the likelihood of systemic exposure to a structurally intact and biologically active macromolecule, thus informing on the safety of proteins for human and animal consumption. Therefore, the purpose of standardized in vitro degradation studies that are performed during protein safety assessments is to distinguish whether proteins of interest are susceptible or resistant to pepsin degradation via a study design that enables study-to-study comparison. Attempting to assess pepsin degradation under a wide-range of possible physiological conditions poses a problem because of the lack of robust and consistent data collected under a large-range of sub-optimal conditions, which undermines the needs to harmonize in vitro degradation conditions. This report systematically compares the effects of pH, incubation time, and pepsin-to-substrate protein ratio on the relative degradation of five dietary proteins: three pepsin susceptible proteins [ribulose 1,5-bisphosphate carboxylase-oxygenase (Rubisco), horseradish peroxidase (HRP), hemoglobin (Hb)], and two pepsin resistant proteins [lipid transfer protein (LTP) and soybean trypsin inhibitor (STI)]. The results indicate that proteins susceptible to pepsin degradation are readily distinguishable from pepsin-resistant proteins when the reaction conditions are within the well-characterized optima for pepsin. The current standardized in vitro pepsin resistant assay with low pH and high pepsin-to-substrate ratio fits this purpose. Using non-optimal pH and/or pepsin-to-substrate protein ratios resulted in susceptible proteins no longer being reliably degraded by this stomach enzyme, which compromises the ability of this in vitro assay to distinguish between resistant and susceptible proteins and, therefore, no longer providing useful data to an overall weight-of-evidence approach to assessing safety of proteins.
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Affiliation(s)
- Rong Wang
- Monsanto Company, St. Louis, Missouri, United States of America
- * E-mail:
| | | | | | | | - Jason M. Ward
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Thomas C. Lee
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Zi L. Liu
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Bin Li
- Monsanto Company, St. Louis, Missouri, United States of America
| | - Kevin C. Glenn
- Monsanto Company, St. Louis, Missouri, United States of America
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23
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Bøgh KL, Madsen CB. Food Allergens: Is There a Correlation between Stability to Digestion and Allergenicity? Crit Rev Food Sci Nutr 2017; 56:1545-67. [PMID: 25607526 DOI: 10.1080/10408398.2013.779569] [Citation(s) in RCA: 89] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Food allergy is a major health problem in the Western countries, affecting 3-8% of the population. It has not yet been established what makes a dietary protein a food allergen. Several characteristics have been proposed to be shared by food allergens. One of these is resistance to digestion. This paper reviews data from digestibility studies on purified food allergens and evaluates the predictive value of digestibility tests on the allergenic potential. We point out that food allergens do not necessarily resist digestion. We discuss how the choice of in vitro digestibility assay condition and the method used for detection of residual intact protein as well as fragments hereof may greatly influence the outcome as well as the interpretation of results. The finding that digests from food allergens may retain allergenicity, stresses the importance of using immunological assays for evaluating the allergenic potential of food allergen digestion products. Studies assessing the allergenicity of digestion products, by either IgE-binding, elicitation or sensitizing capacity, shows that digestion may abolish, decrease, have no effect, or even increase the allergenicity of food allergens. Therefore, the predictive value of the pepsin resistance test for assessing the allergenic potential of novel proteins can be questioned.
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Affiliation(s)
- Katrine Lindholm Bøgh
- a National Food Institute , Division for Diet, Disease Prevention and Toxicology, Technical University of Denmark , Søborg , Denmark
| | - Charlotte Bernhard Madsen
- a National Food Institute , Division for Diet, Disease Prevention and Toxicology, Technical University of Denmark , Søborg , Denmark
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24
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Rapid simulated gastric fluid digestion of in-seed/grain proteins expressed in genetically engineered crops. Regul Toxicol Pharmacol 2016; 81:106-112. [DOI: 10.1016/j.yrtph.2016.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 08/02/2016] [Accepted: 08/03/2016] [Indexed: 01/26/2023]
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25
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Zhang Y, Li C, Liu Y, Wang X, Dong P, Liang X. Mechanism of extraordinary DNA digestion by pepsin. Biochem Biophys Res Commun 2016; 472:101-7. [DOI: 10.1016/j.bbrc.2016.02.073] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 02/18/2016] [Indexed: 11/29/2022]
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26
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Siruguri V, Bharatraj DK, Vankudavath RN, Rao Mendu VV, Gupta V, Goodman RE. Evaluation of Bar, Barnase, and Barstar recombinant proteins expressed in genetically engineered Brassica juncea (Indian mustard) for potential risks of food allergy using bioinformatics and literature searches. Food Chem Toxicol 2015; 83:93-102. [DOI: 10.1016/j.fct.2015.06.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2015] [Revised: 06/02/2015] [Accepted: 06/03/2015] [Indexed: 11/26/2022]
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27
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Koch MS, Ward JM, Levine SL, Baum JA, Vicini JL, Hammond BG. The food and environmental safety of Bt crops. FRONTIERS IN PLANT SCIENCE 2015; 6:283. [PMID: 25972882 PMCID: PMC4413729 DOI: 10.3389/fpls.2015.00283] [Citation(s) in RCA: 97] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 04/08/2015] [Indexed: 05/28/2023]
Abstract
Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.
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28
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Koch MS, Ward JM, Levine SL, Baum JA, Vicini JL, Hammond BG. The food and environmental safety of Bt crops. FRONTIERS IN PLANT SCIENCE 2015; 6:283. [PMID: 25972882 DOI: 10.3389/fpls.2015.0028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Accepted: 04/08/2015] [Indexed: 05/28/2023]
Abstract
Bacillus thuringiensis (Bt) microbial pesticides have a 50-year history of safety in agriculture. Cry proteins are among the active insecticidal ingredients in these pesticides, and genes coding for Cry proteins have been introduced into agricultural crops using modern biotechnology. The Cry gene sequences are often modified to enable effective expression in planta and several Cry proteins have been modified to increase biological activity against the target pest(s). Additionally, the domains of different but structurally conserved Cry proteins can be combined to produce chimeric proteins with enhanced insecticidal properties. Environmental studies are performed and include invertebrates, mammals, and avian species. Mammalian studies used to support the food and feed safety assessment are also used to support the wild mammal assessment. In addition to the NTO assessment, the environmental assessment includes a comparative assessment between the Bt crop and the appropriate conventional control that is genetically similar but lacks the introduced trait to address unintended effects. Specific phenotypic, agronomic, and ecological characteristics are measured in the Bt crop and the conventional control to evaluate whether the introduction of the insect resistance has resulted in any changes that might cause ecological harm in terms of altered weed characteristics, susceptibility to pests, or adverse environmental impact. Additionally, environmental interaction data are collected in field experiments for Bt crop to evaluate potential adverse effects. Further to the agronomic and phenotypic evaluation, potential movement of transgenes from a genetically modified crop plants into wild relatives is assessed for a new pest resistance gene in a new crop. This review summarizes the evidence for safety of crops containing Cry proteins for humans, livestock, and other non-target organisms.
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29
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Mathur C, Kathuria PC, Dahiya P, Singh AB. Lack of detectable allergenicity in genetically modified maize containing "Cry" proteins as compared to native maize based on in silico & in vitro analysis. PLoS One 2015; 10:e0117340. [PMID: 25706412 PMCID: PMC4338076 DOI: 10.1371/journal.pone.0117340] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2014] [Accepted: 12/23/2014] [Indexed: 12/26/2022] Open
Abstract
Background Genetically modified, (GM) crops with potential allergens must be evaluated for safety and endogenous IgE binding pattern compared to native variety, prior to market release. Objective To compare endogenous IgE binding proteins of three GM maize seeds containing Cry 1Ab,1Ac,1C transgenic proteins with non GM maize. Methods An integrated approach of in silico & in vitro methods was employed. Cry proteins were tested for presence of allergen sequence by FASTA in allergen databases. Biochemical assays for maize extracts were performed. Specific IgE (sIgE) and Immunoblot using food sensitized patients sera (n = 39) to non GM and GM maize antigens was performed. Results In silico approaches, confirmed for non sequence similarity of stated transgenic proteins in allergen databases. An insignificant (p> 0.05) variation in protein content between GM and non GM maize was observed. Simulated Gastric Fluid (SGF) revealed reduced number of stable protein fractions in GM then non GM maize which might be due to shift of constituent protein expression. Specific IgE values from patients showed insignificant difference in non GM and GM maize extracts. Five maize sensitized cases, recognized same 7 protein fractions of 88-28 kD as IgE bindng in both GM and non-GM maize, signifying absence of variation. Four of the reported IgE binding proteins were also found to be stable by SGF. Conclusion Cry proteins did not indicate any significant similarity of >35% in allergen databases. Immunoassays also did not identify appreciable differences in endogenous IgE binding in GM and non GM maize.
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Affiliation(s)
- Chandni Mathur
- CSIR-Institute of Genomics & Integrative Biology, Delhi University Campus, Delhi, India
| | | | - Pushpa Dahiya
- Maharishi Dayanand University, Rohtak, Haryana, India
| | - Anand B. Singh
- CSIR-Institute of Genomics & Integrative Biology, Delhi University Campus, Delhi, India
- * E-mail:
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30
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Multiplex comparison of the digestibility of allergenic and non-allergenic proteins in rice grains by in vitro digestion. Food Chem 2015; 168:606-14. [DOI: 10.1016/j.foodchem.2014.07.089] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2013] [Revised: 06/18/2014] [Accepted: 07/16/2014] [Indexed: 11/23/2022]
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31
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Purification, characterization and safety assessment of the introduced cold shock protein B in DroughtGard maize. Regul Toxicol Pharmacol 2014; 71:164-73. [PMID: 25545317 DOI: 10.1016/j.yrtph.2014.12.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 12/17/2014] [Accepted: 12/18/2014] [Indexed: 11/21/2022]
Abstract
DroughtGard maize was developed through constitutive expression of cold shock protein B (CSPB) from Bacillus subtilis to improve performance of maize (Zea mays) under water-limited conditions. B. subtilis commonly occurs in fermented foods and CSPB has a history of safe use. Safety studies were performed to further evaluate safety of CSPB introduced into maize. CSPB was compared to proteins found in current allergen and protein toxin databases and there are no sequence similarities between CSPB and known allergens or toxins. In order to validate the use of Escherichia coli-derived CSPB in other safety studies, physicochemical and functional characterization confirmed that the CSPB produced by DroughtGard possesses comparable molecular weight, immunoreactivity, and functional activity to CSPB produced from E. coli and that neither is glycosylated. CSPB was completely digested with sequential exposure to pepsin and pancreatin for 2 min and 30 s, respectively, suggesting that CSPB will be degraded in the mammalian digestive tract and would not be expected to be allergenic. Mice orally dosed with CSPB at 2160 mg/kg, followed by analysis of body weight gains, food consumption and clinical observations, showed no discernible adverse effects. This comprehensive safety assessment indicated that the CSPB protein from DroughtGard is safe for food and feed consumption.
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32
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Moran DL, Tetteh AO, Goodman RE, Underwood MY. Safety assessment of the calcium-binding protein, apoaequorin, expressed by Escherichia coli. Regul Toxicol Pharmacol 2014; 69:243-9. [DOI: 10.1016/j.yrtph.2014.04.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2014] [Revised: 04/11/2014] [Accepted: 04/12/2014] [Indexed: 10/25/2022]
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Panda R, Ariyarathna H, Amnuaycheewa P, Tetteh A, Pramod SN, Taylor SL, Ballmer-Weber BK, Goodman RE. Challenges in testing genetically modified crops for potential increases in endogenous allergen expression for safety. Allergy 2013; 68:142-51. [PMID: 23205714 DOI: 10.1111/all.12076] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/14/2012] [Indexed: 11/29/2022]
Abstract
Premarket, genetically modified (GM) plants are assessed for potential risks of food allergy. The major risk would be transfer of a gene encoding an allergen or protein nearly identical to an allergen into a different food source, which can be assessed by specific serum testing. The potential that a newly expressed protein might become an allergen is evaluated based on resistance to digestion in pepsin and abundance in food fractions. If the modified plant is a common allergenic source (e.g. soybean), regulatory guidelines suggest testing for increases in the expression of endogenous allergens. Some regulators request evaluating endogenous allergens for rarely allergenic plants (e.g. maize and rice). Since allergic individuals must avoid foods containing their allergen (e.g. peanut, soybean, maize, or rice), the relevance of the tests is unclear. Furthermore, no acceptance criteria are established and little is known about the natural variation in allergen concentrations in these crops. Our results demonstrate a 15-fold difference in the major maize allergen, lipid transfer protein between nine varieties, and complex variation in IgE binding to various soybean varieties. We question the value of evaluating endogenous allergens in GM plants unless the intent of the modification was production of a hypoallergenic crop.
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Affiliation(s)
- R Panda
- Food Allergy Research and Resource Program, University of Nebraska, Lincoln, NE 68583, USA
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34
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Almond RJ, Flanagan BF, Kimber I, Dearman RJ. Influence of protein expression system on elicitation of IgE antibody responses: experience with lactoferrin. Toxicology 2012; 301:50-7. [PMID: 22813905 DOI: 10.1016/j.tox.2012.06.018] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/11/2012] [Accepted: 06/25/2012] [Indexed: 12/21/2022]
Abstract
With increased interest in genetically modified (GM) crop plants there is an important need to understand the properties that contribute to the ability of such novel proteins to provoke immune and/or allergic responses. One characteristic that may be relevant is glycosylation, particularly as novel expression systems (e.g. bacterial to plant) will impact on the protein glycoprofile. The allergenicity (IgE inducing) and immunogenicity (IgG inducing) properties of wild type native human lactoferrin (NLF) from human milk (hm) and neutrophil granules (n) and a recombinant molecule produced in rice (RLF) have been assessed. These forms of lactoferrin have identical amino acid sequences, but different glycosylation patterns: hmNLF and nNLF have complex glycoprofiles including Lewis (Le)(x) structures, with particularly high levels of Le(x) expressed by nNLF, whereas RLF is simpler and rich in mannose residues. Antibody responses induced in BALB/c strain mice by intraperitoneal exposure to the different forms of lactoferrin were characterised. Immunisation with both forms of NLF stimulated substantial IgG and IgE antibody responses. In contrast, the recombinant molecule was considerably less immunogenic and failed to stimulate detectable IgE, irrespective of endotoxin and iron content. The glycans did not contribute to epitope formation, with equivalent IgE and IgG binding recorded for high titre anti-NLF antisera regardless of whether the immunising NLF or the recombinant molecule were used substrates in the analyses. These data demonstrate that differential glycosylation profiles can have a profound impact on protein allergenicity and immunogenicity, with mannose and Le(x) exhibiting opposing effects. These results have clear relevance for characterising the allergenic hazards of novel proteins in GM crops.
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Suggested improvements for the allergenicity assessment of genetically modified plants used in foods. Curr Allergy Asthma Rep 2011; 11:317-24. [PMID: 21487714 PMCID: PMC3130127 DOI: 10.1007/s11882-011-0195-6] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Genetically modified (GM) plants are increasingly used for food production and industrial applications. As the global population has surpassed 7 billion and per capita consumption rises, food production is challenged by loss of arable land, changing weather patterns, and evolving plant pests and disease. Previous gains in quantity and quality relied on natural or artificial breeding, random mutagenesis, increased pesticide and fertilizer use, and improved farming techniques, all without a formal safety evaluation. However, the direct introduction of novel genes raised questions regarding safety that are being addressed by an evaluation process that considers potential increases in the allergenicity, toxicity, and nutrient availability of foods derived from the GM plants. Opinions vary regarding the adequacy of the assessment, but there is no documented proof of an adverse effect resulting from foods produced from GM plants. This review and opinion discusses current practices and new regulatory demands related to food safety.
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Clement F, Venkatesh YP. Dietary garlic (Allium sativum) lectins, ASA I and ASA II, are highly stable and immunogenic. Int Immunopharmacol 2010; 10:1161-9. [DOI: 10.1016/j.intimp.2010.06.022] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2010] [Revised: 06/08/2010] [Accepted: 06/22/2010] [Indexed: 12/16/2022]
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Guimaraes V, Drumare MF, Lereclus D, Gohar M, Lamourette P, Nevers MC, Vaisanen-Tunkelrott ML, Bernard H, Guillon B, Créminon C, Wal JM, Adel-Patient K. In vitro digestion of Cry1Ab proteins and analysis of the impact on their immunoreactivity. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2010; 58:3222-31. [PMID: 20136083 DOI: 10.1021/jf903189j] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
A pepsin resistance test performed at pH 1.2 and with high pepsin to protein ratio is one of the steps of the weight-of-evidence approach used for assessment of allergenicity of new proteins. However, the use of other in vitro digestibility tests, performed in more physiologically relevant conditions and in combination with immunological assays so as to increase the value of the information gained from the studies of stability of a novel protein to digestion for the overall allergenicity assessment, has been proposed. This study then aimed to investigate the stability to digestion of Cry1Ab protoxin and toxin, insecticidal proteins expressed in genetically modified crops, using simulated gastric fluid (SGF) at different pH values and pepsin-to-substrate ratios, in the presence or absence of physiological surfactant phosphatidylcholine (PC). Electrophoresis and immunoblot patterns and residual immunoreactivity of digesta were analyzed. Although Cry1Ab protoxin is extensively degraded at pH 1.2 with high pepsin-to-protein ratio, it is only slightly degraded at pH 2.0 and conserved its immunoreactivity. Furthermore, Cry1Ab proteins were demonstrated to be stable in a more physiologically relevant in vitro digestibility test (pH 2.5, pepsin-to-substrate ratio 1:20 (w/w) with PC). Factors such as pH, SGF composition, and pepsin-to-substrate ratio then greatly influence the digestion of Cry1Ab proteins, confirming that new and more physiologically relevant in vitro digestibility tests should be also considered to study the relationship between the resistance of a protein to digestion and its allergenicity.
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Affiliation(s)
- Valeria Guimaraes
- INRA, UR496, Laboratoire d'Immuno-Allergie Alimentaire, F-78352 Jouy-en-Josas, France
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Should digestion assays be used to estimate persistence of potential allergens in tests for safety of novel food proteins? Clin Mol Allergy 2009; 7:1. [PMID: 19146693 PMCID: PMC2632610 DOI: 10.1186/1476-7961-7-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2008] [Accepted: 01/15/2009] [Indexed: 12/20/2022] Open
Abstract
Food allergies affect an estimated 3 to 4% of adults and up to 8% of children in developed western countries. Results from in vitro simulated gastric digestion studies with purified proteins are routinely used to assess the allergenic potential of novel food proteins. The digestion of purified proteins in simulated gastric fluid typically progresses in an exponential fashion allowing persistence to be quantified using pseudo-first-order rate constants or half lives. However, the persistence of purified proteins in simulated gastric fluid is a poor predictor of the allergenic status of food proteins, potentially due to food matrix effects that can be significant in vivo. The evaluation of the persistence of novel proteins in whole, prepared food exposed to simulated gastric fluid may provide a more correlative result, but such assays should be thoroughly validated to demonstrate a predictive capacity before they are accepted to predict the allergenic potential of novel food proteins.
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