GM Maize Induces Changes in Mice Immune Response

A new report by the Italian government’s National Institute of Research on Food and Nutrition which is published in the Journal of Agricultural Food Chemistry has found significant changes in the immune response of young and old mice that have been fed the GM maize MON 810.

In the study, weaning and old mice were fed a diet containing MON810 or its parental control maize or a pellet diet containing GM-free maize for 30 and 90 days. Significant differences in the percentages of several lymphocyte populations and subsets were documented in both weaning and old mice that were fed with GM maize, compared with the control and GM-free maize diets. There was also an increase of several cytokines in serum, all involved in allergic and inflammatory responses, in mice fed with MON810. These changes were not detected in the mice fed on non-GM diets. The increase of these cytokines is a further indicator of immune perturbations caused by MON 810 maize.

Because the MON810 and its parental control maize given to the animals were grown simultaneously in neighbouring fields, using the same agricultural techniques and had the same external climatic conditions, this eliminates or reduces environmental variables. Likewise, both the GM and non-GM maize had the same nutritiona! l composition and were similarly balanced, ruling out improper nutrition causing the observed effects. Together with other data eliminating other probable causes of the changes, this indicates that the observed immunophenotype changes were likely due to the insertion of the Cry1Ab coding sequence.

The immune disturbances are significant also in view of other findings whereby proteomic analysis identified 43 proteins that were up- or down-regulated in the MON 810 maize seeds compared with the parental control, likely as a result of the Cry1Ab gene insertion, among them a well-known allergenic protein, that was not present in the parental strain.

The scientists concluded that the results obtained indicate that the consumption of MON810 maize induced alterations in intestinal and peripheral immune response of weaning and old mice. Although the significance of these data remains to be clarified to establish whether these alterations reflect significant immune dysfunctions, these results suggest the importance of considering the gut and peripheral immune response to the whole GM crop, as well as the age, in the GMO safety evaluation. Previous assessments of GMO immune adverse impacts had largely looked only at the pure recombinant protein, not the whole GMO.

<!--[if !supportLineBreakNewLine]-->
<!--[endif]-->These latest findings, together with a number of other studies, which have raised concerns on the health safety of GM food and feed, further strengthen the need for caution in approving and releasing GM products for consumption.

Website: www.biosafety-info.net and www.twnside.org.sg

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Item 1

Intestinal and Peripheral Immune Response to MON810 Maize Ingestion in
Weaning and Old Mice
<http://pubs.acs.org/doi/abs/10.1021/jf802059w>

Alberto Finamore, Marianna Roselli, Serena Britti, Giovanni Monastra,
Roberto Ambra, Aida Turrini and Elena Mengheri*

Istituto Nazionale di Ricerca per gli Alimenti e la Nutrizione, Via
Ardeatina 546, 00178 Roma, Italy
J. Agric. Food Chem., Article ASAP
DOI: 10.1021/jf802059w
Publication Date (Web): November 14, 2008
Copyright © 2008 American Chemical Society
* Corresponding author (e-mail mengheri@inran.it; telephone
+39-06-51494523; fax +39-06-51494550).

Abstract

This study evaluated the gut and peripheral immune response to genetically modified (GM) maize in mice in vulnerable conditions. Weaning and old mice were fed a diet containing MON810 or its parental control maize or a pellet diet containing a GM-free maize for 30 and 90 days. The immunophenotype of intestinal intraepithelial, spleen, and blood lymphocytes of control maize fed mice was similar to that of pellet fed mice. As compared to control maize, MON810 maize induced alterations in the percentage of T and B cells and of CD4+, CD8+, cdT, and abT subpopulations of weaning and old mice fed for 30 or 90 days, respectively, at the gut and peripheral sites. An increase of serum IL-6, IL-13, IL-12p70, and MIP-1b after MON810 feeding was also found. These results suggest the importance of the gut and peripheral immune response to GM crop ingestion as well as the age of the consumer in the GMO safety evaluation.

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Item 2

ISIS Press Release 19/11/08
GM Maize Disturbs Immune System of Young and Old Mice
New research add to the weight of damning evidence against the safety of GM food Dr. Mae-Wan Ho

The Italian government’s National Institute of Research on Food and Nutrition has just published a report online in the Journal of Agricultural Food Chemistry documenting significant disturbances in the immune system of young and old mice that have been fed the GM maize MON 810 [1]. This follows hot on the heels of results released by the Austrian government showing that GM Maize Reduces Fertility & Deregulates Genes in Mice (SiS 41) [2]. These revelations confirm a string of previous findings on adverse health impacts of GM food and feed, leave us in little doubt that GM is! Dangerous and Futile (SiS 40) [3]. Proponents should stop misleading the public that GM food and feed is safe.

The GM maize and the parental non-GM variety from which it was derived, were grown simultaneously in neighbouring fields in Landriano, Italy, from seeds provided by SeedsEmporda (Girona, Spain). The control maize flour from the non-GM parental strain had a low level of GMO contamination (0.29 percent by PCR test) but only the GM maize had the specific gene coding for the toxin Cry1Ab that acts as a pesticide.

The GM and non-GM maize were also analysed for levels of the fungal aflatoxins B1, B2, G1, G2, fumonisin B1 (FB1), deoxynivalenol (DON), ochratoxin, and zeralenon, that frequently contaminate maize grains. The values were below the maximum allowed in Europe, except for FB1 (1350 and 2450 mg/kg) and DON (1300 and 650 mg/kg) in GM and non-GM maize respectively.

The diets were formulated according to accepted standards and contained 50 percent MON810 or its parental control maize flour. A standard pellet diet containing about 50 percent of commercial non GM maize was also used, which did not contain CrylAb by PCR test.

Weaning mice, 21 days old, were fed with the diets for 30 and 90 days, and the old mice, 18 to 19 months, were fed for 90 days on the test diets; and male Balb/c mice were used in all the experiments.

There were no differences in the mean body weight or in food consumed between the GM-fed and control mice. These are the ‘agronomic’ characteristics typically measured in feeding tests, and all too often, the only characteristics measured.

The total number of white blood cells in the small intestine, spleen and blood were not different. However, there were significant differences in the percentages of T and B cells, and of CD4+, CD8+, gdT+, and mbT+ subpopulations in both weaning and old mice that were GM-fed for 30 and 90 days respectively compared with controls. These changes appeared in the gut, spleen and blood, and were accompanied by increase in blood cytokines IL-6, IL-13, IL-12p70, and MIP-1b, all involved in allergic and inflammatory responses. These changes were not detected in the mice fed the commercial non-GM pellet diet.

The greatest effects were the weaning mice fed for 30 days on GM maize, whereas those fed for 90 days only had increased B cells. In the old mice, the induced changes were similar to those found for the weaning mice fed for 30 days. These results show that very young and old mice are more susceptible to immunological insults. By the time the mice were 111 days old (90+21), a degree of tolerance had been established, so that the disturbances were reduced.

The immune disturbances are significant also in view of findings from another laboratory [4]; proteomic analysis identified 43 proteins that were up or down regulated in the MON 810 maize seeds compared with the parental strain, among them a 50 kda g-zein, a well-known allergenic protein [5], that was not present in the parental strain.

It is clear that genetic modification is inherently hazardous, as it invariably result in unpredictable and uncontrollable changes in the genome and the epigenome (pattern of gene expression) that impact on safety.

References
Finamore A, Roselli M, Britti S, Monastra G, Ambra R, Turrini A and Mengheri E. Intestinal and peripheral immune response to MON810 maize ingestion in weaning and old mice. J Agric food Chem, http://pubs.ac.org, 16 November 2008
Ho MW. GM maize reduces fertility and deregulates genes in mice. Science in Society 41 (to appear)
Ho MW. GM is dangerous and futile. Science in Society 40 (in press).
Zolla L, Rinalducci S, Antonioli P, Righetti PG. Proteomics as a complementary tool for identifying unintended side effects occurring in transgenic maize seeds as a sresultof genetic modification. J. Proteome Res 2008, 7, 1850-61.
Pasini G, Simonato B, Curioni A, Vincenzi S, Cristaudo Q, Santucci B, Peruffo AD, Giannattasio M. IgE-mediated allergy to corn: a 50 kDa protein, belonging to the reduced soluble proteins, is a major allergen. Allergy 2002, 37, 98-106.