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Increased biodiversity in the environment improves the humoral response of rats.

Pi C, Allott EH, Ren D, Poulton S, Lee SY, Perkins S, Everett ML, Holzknecht ZE, Lin SS, Parker W - PLoS ONE (2015)

Bottom Line: This comparison serves as an indicator of what sorts of changes might exist between modern humans living in Western culture compared to our hunter-gatherer ancestors.However, immunological experiments on wild-caught animals are difficult and potentially confounded by increased levels of stress in the captive animals.However, animals housed in the enriched biodiversity setting demonstrated an increased mean humoral response to T-independent and T-dependent antigens and increased levels of "natural" antibodies directed at a xenogeneic protein and at an autologous tissue extract that were not used as immunogens.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgery, Duke University Medical Center, Durham, NC, United States of America.

ABSTRACT
Previous studies have compared the immune systems of wild and of laboratory rodents in an effort to determine how laboratory rodents differ from their naturally occurring relatives. This comparison serves as an indicator of what sorts of changes might exist between modern humans living in Western culture compared to our hunter-gatherer ancestors. However, immunological experiments on wild-caught animals are difficult and potentially confounded by increased levels of stress in the captive animals. In this study, the humoral immune responses of laboratory rats in a traditional laboratory environment and in an environment with enriched biodiversity were examined following immunization with a panel of antigens. Biodiversity enrichment included colonization of the laboratory animals with helminths and co-housing the laboratory animals with wild-caught rats. Increased biodiversity did not apparently affect the IgE response to peanut antigens following immunization with those antigens. However, animals housed in the enriched biodiversity setting demonstrated an increased mean humoral response to T-independent and T-dependent antigens and increased levels of "natural" antibodies directed at a xenogeneic protein and at an autologous tissue extract that were not used as immunogens.

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Binding of natural anti-rat muscle IgG in the serum of biome depleted and biome enriched rats as evaluated by immunoblotting.(A) Rat muscle extracts were separated by SDS PAGE and probed by immunoblotting as described in the Methods. The analysis was limited to 15 animals (n = 8 biome enriched; lanes E1 through E8, and n = 7 biome depleted; lanes D1 through D7) due to size constraints of the gel. A control strip with no serum is labeled “C”, and indicates reactivity of the anti-IgG conjugate with muscle-derived antigens. (B) The number of bands recognized by natural IgG in individual sera (p = 0.017) and the total reactivity of natural IgG from each serum sample (p = 0.040) are shown, with the bars indicating the mean and standard error. (C) The distribution of bands as a function of band size is shown. For this analysis, the average number of bands in biome depleted and biome enriched rats (Y-axis) was plotted on linear and log scales (main figure and figure inset, respectively) versus different band sizes (X-axis).
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pone.0120255.g007: Binding of natural anti-rat muscle IgG in the serum of biome depleted and biome enriched rats as evaluated by immunoblotting.(A) Rat muscle extracts were separated by SDS PAGE and probed by immunoblotting as described in the Methods. The analysis was limited to 15 animals (n = 8 biome enriched; lanes E1 through E8, and n = 7 biome depleted; lanes D1 through D7) due to size constraints of the gel. A control strip with no serum is labeled “C”, and indicates reactivity of the anti-IgG conjugate with muscle-derived antigens. (B) The number of bands recognized by natural IgG in individual sera (p = 0.017) and the total reactivity of natural IgG from each serum sample (p = 0.040) are shown, with the bars indicating the mean and standard error. (C) The distribution of bands as a function of band size is shown. For this analysis, the average number of bands in biome depleted and biome enriched rats (Y-axis) was plotted on linear and log scales (main figure and figure inset, respectively) versus different band sizes (X-axis).

Mentions: The repertoire of natural antibodies recognizing autologous antigens (rat muscle tissue extract) in biome enriched and biome depleted animals was evaluated by Western blotting (Figs. 6 and 7). The results suggest that the concentration of natural antibodies is dramatically increased by biome enrichment. The binding of IgM to autologous antigens (Fig. 6) was characterized by a moderate (11%) difference in the average number of antigens recognized (Fig. 6B), but given the high density of bands, it is possible that the presence of overlapping bands may have caused an underestimation of the bands recognized, particularly in the lanes with high intensity of binding. Biome depleted animals had about 34% less binding of IgM to autologous antigens, on average, and a distribution analysis showed enhanced binding of IgM from biome enriched animals to both high intensity and low intensity bands on the membranes (Fig. 6C). These results suggest that the increase in IgM binding to autologous antigens as a result of biome enrichment may be due to both increased concentrations of antibody and an increased range of specificity of the repertoire. Similar results were obtained when examining the IgG repertoire (Fig. 7), again suggesting that the increase in IgG binding to autologous antigens as a result of biome enrichment may be due to both increased concentrations of antibody and increased range of specificity of the repertoire.


Increased biodiversity in the environment improves the humoral response of rats.

Pi C, Allott EH, Ren D, Poulton S, Lee SY, Perkins S, Everett ML, Holzknecht ZE, Lin SS, Parker W - PLoS ONE (2015)

Binding of natural anti-rat muscle IgG in the serum of biome depleted and biome enriched rats as evaluated by immunoblotting.(A) Rat muscle extracts were separated by SDS PAGE and probed by immunoblotting as described in the Methods. The analysis was limited to 15 animals (n = 8 biome enriched; lanes E1 through E8, and n = 7 biome depleted; lanes D1 through D7) due to size constraints of the gel. A control strip with no serum is labeled “C”, and indicates reactivity of the anti-IgG conjugate with muscle-derived antigens. (B) The number of bands recognized by natural IgG in individual sera (p = 0.017) and the total reactivity of natural IgG from each serum sample (p = 0.040) are shown, with the bars indicating the mean and standard error. (C) The distribution of bands as a function of band size is shown. For this analysis, the average number of bands in biome depleted and biome enriched rats (Y-axis) was plotted on linear and log scales (main figure and figure inset, respectively) versus different band sizes (X-axis).
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4390306&req=5

pone.0120255.g007: Binding of natural anti-rat muscle IgG in the serum of biome depleted and biome enriched rats as evaluated by immunoblotting.(A) Rat muscle extracts were separated by SDS PAGE and probed by immunoblotting as described in the Methods. The analysis was limited to 15 animals (n = 8 biome enriched; lanes E1 through E8, and n = 7 biome depleted; lanes D1 through D7) due to size constraints of the gel. A control strip with no serum is labeled “C”, and indicates reactivity of the anti-IgG conjugate with muscle-derived antigens. (B) The number of bands recognized by natural IgG in individual sera (p = 0.017) and the total reactivity of natural IgG from each serum sample (p = 0.040) are shown, with the bars indicating the mean and standard error. (C) The distribution of bands as a function of band size is shown. For this analysis, the average number of bands in biome depleted and biome enriched rats (Y-axis) was plotted on linear and log scales (main figure and figure inset, respectively) versus different band sizes (X-axis).
Mentions: The repertoire of natural antibodies recognizing autologous antigens (rat muscle tissue extract) in biome enriched and biome depleted animals was evaluated by Western blotting (Figs. 6 and 7). The results suggest that the concentration of natural antibodies is dramatically increased by biome enrichment. The binding of IgM to autologous antigens (Fig. 6) was characterized by a moderate (11%) difference in the average number of antigens recognized (Fig. 6B), but given the high density of bands, it is possible that the presence of overlapping bands may have caused an underestimation of the bands recognized, particularly in the lanes with high intensity of binding. Biome depleted animals had about 34% less binding of IgM to autologous antigens, on average, and a distribution analysis showed enhanced binding of IgM from biome enriched animals to both high intensity and low intensity bands on the membranes (Fig. 6C). These results suggest that the increase in IgM binding to autologous antigens as a result of biome enrichment may be due to both increased concentrations of antibody and an increased range of specificity of the repertoire. Similar results were obtained when examining the IgG repertoire (Fig. 7), again suggesting that the increase in IgG binding to autologous antigens as a result of biome enrichment may be due to both increased concentrations of antibody and increased range of specificity of the repertoire.

Bottom Line: This comparison serves as an indicator of what sorts of changes might exist between modern humans living in Western culture compared to our hunter-gatherer ancestors.However, immunological experiments on wild-caught animals are difficult and potentially confounded by increased levels of stress in the captive animals.However, animals housed in the enriched biodiversity setting demonstrated an increased mean humoral response to T-independent and T-dependent antigens and increased levels of "natural" antibodies directed at a xenogeneic protein and at an autologous tissue extract that were not used as immunogens.

View Article: PubMed Central - PubMed

Affiliation: Department of Surgery, Duke University Medical Center, Durham, NC, United States of America.

ABSTRACT
Previous studies have compared the immune systems of wild and of laboratory rodents in an effort to determine how laboratory rodents differ from their naturally occurring relatives. This comparison serves as an indicator of what sorts of changes might exist between modern humans living in Western culture compared to our hunter-gatherer ancestors. However, immunological experiments on wild-caught animals are difficult and potentially confounded by increased levels of stress in the captive animals. In this study, the humoral immune responses of laboratory rats in a traditional laboratory environment and in an environment with enriched biodiversity were examined following immunization with a panel of antigens. Biodiversity enrichment included colonization of the laboratory animals with helminths and co-housing the laboratory animals with wild-caught rats. Increased biodiversity did not apparently affect the IgE response to peanut antigens following immunization with those antigens. However, animals housed in the enriched biodiversity setting demonstrated an increased mean humoral response to T-independent and T-dependent antigens and increased levels of "natural" antibodies directed at a xenogeneic protein and at an autologous tissue extract that were not used as immunogens.

Show MeSH