Anim Sci J. 2019;1–8. wileyonlinelibrary.com/journal/asj  | 1© 2019 Japanese Society of Animal Science

1  | INTRODUC TION

Soybean is a high- quality oilseed legume and major protein source (Zhao, Qin, Tian, & Sun, 2014) that has been widely used in livestock and poultry feed owing to excellent functional prop-erties, physiological activities, high nutrition, and low cost (Wang, Qin, Sun, & Zhao, 2014). However, soybeans contain various an-tinutritional factors (ANFs), such as soybean agglutinin, soybean allergenic proteins, and trypsin inhibitors. These ANFs lead to allergic reactions in young animals and result in immune dys-function, growth inhibition, and diarrhea (Chen et al., 2011; Zhao et al., 2014). Previous studies have shown that soybean antigen protein is the major sensitizing factor in soybeans and could be di-vided into 2S, 7S, 11S, and many other components according to their centrifugal sedimentation rates (Catsimpoolas & Ekenstam, 1969). 7S and 11S are the main allergens (Holzhauser et al., 2009). Researchers have reported that high hydrostatic pressure

and ultrasound pretreatment can be used to destroy ANFs (Li, Zhu, Zhou, & Peng, 2012; Wang, Wang, Handa, & Xu, 2017). Additionally, the effects of soybean antigen proteins on the pro-duction performance, immune function, and intestinal function of animals have been analyzed, and the sensitization mechanism of soybean antigen protein has been explored (Sun, Liu, Wang, Liu, & Feng, 2013; Wu, Cao, Meng et al., 2016; Wu, Cao, Ren et al., 2016; Wu, Zhang et al., 2016).

Mucosal tissues contain congenital and acquired immune cells whose surface is the location of the secretory immune system, and the main immunoglobulin is sIgA (Lamichhane, Azegamia, & Kiyono, 2014). In addition, histamine is a crucial mediator released by acti-vated mast cells (Potts et al., 2016; Sun, Li, Li, Dong, & Wang, 2008). To date, almost no studies have examined the effects of prior im-munization with 7S or 11S on histamine content and sIgA and IgA expression in piglets. IgA binds to the J chain to form a dimer or multimer and then binds to sIgA secreted by mucosal epithelial cells, thereby acting as the primary defense of the mucosal immune bar-rier (Peng et al., 2018).

Received:21July2018  |  Revised:1September2018  |  Accepted:2October2018DOI:10.1111/asj.13130

O R I G I N A L A R T I C L E

Effects of 7S and 11S on the intestine of weaned piglets after injection and oral administration of soybean antigen protein

Chenglu Peng | Xuebing Tang | Yingshuang Shu | Mengchu He | Xiaodong Xia |  Yu Zhang | Chengming Cao | Yu Li | Shibin Feng | Xichun Wang  | Jinjie Wu

Chenglu Peng and Xuebing Tang contributed equally to this study.

College of Animal Science and technology, Anhui Agricultural University, Hefei, China

CorrespondenceJinjie Wu, College of Animal Science and Technology, Anhui Agricultural University, Hefei, China.Email: wjj@ahau.edu.cn

Funding informationNational ‘Fu Min Qiang Xian’ Program of China, Grant/Award Number: 2012-745; Project of Modern Agricultural Industry and Technology System of Anhui Province, Grant/Award Number: AHCYJSTX-05/07

AbstractSoybeans are used increasingly in food products because of their health benefits. In this study, we investigated the effect of soybean antigen protein on weaned piglet intestine. Seventy piglets were randomly divided into seven groups with 10 piglets each. At 7 and 14 days of age, groups A–C were injected with saline, and D–G were intramuscularly injected with or orally administered 7S or 11S. Groups B–G were artificially sensitized by dietary 7S or 11S. At 27 days, the small intestinal tissues were collected to determine levels of histamine, sIgA protein, and IgA mRNA. Histamine in B–G was significantly decreased in the duodenum and ileum. Moreover, sIgA expression was higher in all groups than in A, with B/C>D–G and F/G>D/E; the trend in IgA expression was similar. Collectively, these results indicated that soybean antigen protein- immunizing agents decrease sIgA and IgA levels. Additionally, the effect of injection immunization occurred prior to that of oral immunization.

K E Y W O R D S

IgA, immunization, intestine, pig, soybean

2  |     PENG Et al.

Therefore, in this study, we aimed to investigate the effects of prior immunization with 7S or 11S on histamine content, sIgA distri-bution and expression, and IgA mRNA expression in piglets. We used an experimental piglet model injected with or orally administered purified 7S or 11S to eliminate the interference from other compo-nents in soybean meal.

2  | MATERIAL S AND METHODS

2.1 | Preparation of immunizing agents

β- Conglycinin and glycinin were kindly donated by Professor Shuntang Guo from the Food Institute of China Agricultural University (patent number: 200,410,029,589.4, China). Using the roughly separated soy protein as raw materials, alkaline saponifi-cation, isoelectric point precipitation, and gel filtration were used to purify soybean proteins. The purities of the purified 11S and 7S proteins were 93.1% and 92.3% respectively. The soybean antigen protein was mixed with Freund’s adjuvant by ultrasonic mixing to prepare an immunizing agent.

2.2 | Piglets and diets

The experimental piglets were obtained from the College of Animal Science and Technology, Anhui Agricultural University, Hefei, China. Experiments were performed according to the Regulations for the Administration of Affairs Concerning Experimental Animals (Ministry of Science and Technology, China; revised in June 2004) and approved by the ethics committee of Anhui Agricultural University, Anhui, China. Before weaning, 10 piglets were kept in each pen and provided feed and water ad libitum. The piglets were housed in a traditional nursery pen with a 12- hr light/dark cycle, an average ambient humidity of 55%, and a temperature of up to 26–28°C.

The diets were provided in two phases (7–21 days of age and 21–27 days of age) during the experiment. The diets for prewean-ing and postweaning piglets (Table 1) were formulated to meet or exceed nutrient requirements suggested by the National Reaearch Council (1996).

2.3 | Experimental design and sample collection

All piglets were randomly divided by weight and sex into groups A (control group), B (7S- sensitized group), C (11S- sensitized group), D (7S- injection immunized + sensitized group), E (11S- injection im-munized + sensitized group), F (7S- orally immunized + sensitized group), and G (11S- orally immunized + sensitized group), with 10 pig-lets per group. At 7 and 14 days, piglets in groups A, B, and C were injected with physiological saline solution, and the other four groups of piglets were immunized twice by oral administration or injection with 7S or 11S at a dose of 1 mg/kg body weight. At 21 days, all pig-lets were weaned, and piglets in group A were fed a basal diet, while piglets in the six experimental groups were artificially sensitized by

adding 5% 7S or 11S to the basal diet during the experimental period for 7 days.

At the end of the experiment, five piglets from each group were slaughtered by an intracardiac injection of sodium pentobarbital (50 mg/kg body weight) followed by jugular exsanguination. The duodenum, jejunum, and ileum were collected and stored in 3–5 vol-umes of 4% paraformaldehyde solution to measure the average opti-caldensity(OD)valuesofsIgAexpressionbyimmunohistochemicalanalysis. Some samples were stored in liquid nitrogen for detection of relative IgA mRNA expression by quantitative real- time reverse transcription polymerase chain reaction (qRT- PCR), determine the

TABLE  1  Ingredients and nutrient contents of experimental diets (Wu, Cao, Ren et al., 2016)

Experimental diets

Pre- weaning (7–21 days)

Post- weaning (21–27 days)

Ingredients (%)

Corn — 60.85

Dried whole milk 46.00 —

Skimmed milk powder 42.00 —

Soybean meal (expanded)a

— 25.00

Whey powder 10.50 5.00

Fish meal — 5.00

Calcium hydrogen phosphate

— 2.20

Limestone — 0.69

Bran — 0.37

Salt 0.30 0.25

Premixb 1.00 0.49

Choline chloride — 0.15

Total 100.00 100.00

Nutrient levelsc

CP 27.90 20.80

Ca 1.04 0.64

P 0.89 0.51

Lys 1.61 1.06

DE (MJ/kg) 14.5 13.50

Notes. CP, crude protein; DE, digestible energy.aExpanded for eliminating the antigen proteins. bPremix supplies per kg (pre- weaning/post- weaning): vitamin A, 7000/5250 U; vitamin D3, 2000/1050 U; vitamin E, 10/4.5 U; vitamin K3, 2.2/1.2 mg; vitamin B1, 2.375/0.375 mg; vitamin B2, 4.8/1.8 mg; vitamin B6, 0.15/0.15 mg; vita-min B12, 17.5/7.5 lg; niacin, 16/6 mg; Ca- pantothenate, 5.75/3.75 mg; folic acid, 0.85/0.15 mg; biotin, 17.5/7.5 lg; lysine, 0.95/0.75 mg; antioxi-dant, 45/45 lg; enzyme preparation (mixture of amylase, protease, lipase and phytase), 1100/1000 mg; flavor agents, 45/40 mg; sweet agents, 45/40 mg; neomycin, 0/20 mg; Cu (as copper sulfate), 15/15 mg; Fe (as ferrous sulfate), 144/144 mg; Zn (as zinc sulfate), 110/110 mg; Mn (as manganese sulfate), 20.18/10.18 mg; I (as calcium iodide), 0.4/0.4 mg; Se (as sodium selenite), 0.35/0.3 mg. cThe digestible energy is calculated while the other nutrients are analysed.

     |  3PENG Et al.

expression of sIgA protein by western blot and measure the content of histamine by enzyme- linked immunosorbent assay (ELISA).

2.4 | Determination of histamine content

Approximately 0.5 g intestinal segments was dissolved in phosphate- buffered saline. After homogenization, samples were centrifuged at 10,000 g at 4°C for 10 min, and supernatants were obtained. Measurement of histamine levels in the intestine was performed using a swine histamine ELISA kit (Nanjing SenBeiJia Biological Technology Co., Ltd., Nanjing, China), following the manufacturer’s instructions.

2.5 | Determination of relative sIgA positivity

The intestinal tissues of the duodenum, jejunum, and ileum were dehydrated and embedded in paraffin. Paraffin- embedded sections were then used for sIgA determination by immunohistochemistry (method PV6000) as described by Wu, Cao, Ren et al. (2016). The averageODoftheintestinalsIgAwasanalyzedusinganImageProPlus 6.0 image analysis system.

2.6 | Determination of sIgA protein expression by western blotting

Electrophoresis was performed on slab gels comprising 12% acrylamide resolving gels and 5% stacking gels. Proteins were then electroblotted (Bio- Rad, Hercules, CA, USA) onto a polyvinylidene fluoride membrane (Millipore, Temecula, CA, USA). The membranes were blocked with 5% bovine serum albumin for 4 hr at room

temperature and then incubated with appropriately diluted IgA antibody (Proteintech, Chicago, USA). Membranes were washed three times with TBST and incubated with a 1:5,000 dilution of goat anti- rabbit IgG secondary antibody (Zsgb Biotechnology, Beijing, China). The membranes were again washed in TBST three times,andtheresultswereanalyzedusingQuantityOnesoftware(Bio- Rad).

2.7 | Determination of IgA relative mRNA expression

Total RNA was extracted from intestinal samples for qRT- PCR using RNAiso Plus (TaKaRa Biotechnology [Dalian] Co., Ltd., Dalian, China), which was triturated in liquid nitrogen, accord-ing to the manufacturer’s instructions. All of the primers used for qRT- PCR were designed using Primer Premier 5.0 software and synthesized by BGI. The primer sequences were as follows: IgA (forward) 5′-CACCTGCCACCATCTTTCTCCT-3′ and (re-verse) 5′-CCACACTCACCGTCACCGAT-3′; actin (used as a con-trol) (forward) 5′-GCACCACACCTTCTACAA-3′ and (reverse)5′-TCATCTTCTCACGGTTGG-3′. Relative expression of IgAmRNAwas analyzed using the 2−ΔΔCt method.

2.8 | Statistical analysis

All analyses were evaluated by the general linear model procedures of the SAS system (SAS, 2002–2012; Version 9.1.3; SAS Institute, Inc.). Data were expressed as means ± standard deviations (SD). Analysis of variance was used to examine differences between groups. Results with p values of less than 0.05 were considered sta-tistically significant. The statistical software Graph Pad Prism ver-sion 5.01 (GraphPad Software, San Diego, CA, USA) was used to make histograms.

3  | RESULTS

3.1 | Preparation of immunizing agents

As shown in Figure 1, after sodium dodecyl sulfate polyacryla-mide gel electrophoresis, 7S contained three bands, including α, β, and α’ subunits. According to the marked lanes, the corresponding molecular weights of α, β, and α’ were 66.2, 45.0, and 60.0 kDa re-spectively. There were two bands for 11S, including acidic and basic subunits. The molecular weights of these two subunits were 33.0 and 20.0 kDa respectively. Furthermore, the extracted protein had a higher purity, as shown in Figure 1.

3.2 | Effects of 7S and 11S on histamine content

As shown in Figure 2, at 27 days, histamine content in the duode-nums of piglets was significantly decreased in sensitized groups (p < 0.01) compared with that in control group. Histamine content in duodenums of piglets in injection immunized groups was higher

F IGURE  1 Sodium dodecyl sulfate- polyacrylamide gel electrophoresis for preparation of β- conglycinin and glycinin. The left line is a marker, and the molecular weights ranged from 14.4 to 94.0 kDa. Line 1 represents the location and molecular weights of the 7S subunits; line 2 represents the location and molecular weights of the 11S subunits

4  |     PENG Et al.

than that in orally immunized groups (p < 0.01). Histamine content in the jejunums of piglets in group B was significantly lower than that in immunized groups (p < 0.01), and that in 7S- injection im-munized groups was higher than that in 11S- injection immunized groups (p < 0.05). Histamine content in the ileums of piglets in con-trol group and 11S- sensitized group was significantly lower than that in the other treatment groups (p < 0.01), and that in 11S- orally immunized group was lower than that in 11S- injection immunized group (p < 0.05).

3.3 | Effects of 7S and 11S on sIgA expression

Immunohistochemical analysis of sIgA distribution is shown in Figures 3–5. sIgA was detected in the duodenum, jejunum, and ileum, mainly between the lamina propria and gland joints. The negative control group showed no expression. The results are

shown in Table2. OD values of sIgA expression in the intesti-nal sections in experimental groups B (p < 0.01), C (p < 0.05), D (p < 0.05), E (p < 0.05), F (p < 0.01), and G (p < 0.05) were higher than those in control group; specifically, those in sensitized groups were higher than those in immunized groups, and those in orally immunized groups were higher than those in injection immunized groups. Compared with control group, sIgA expression was in-creased in piglets in sensitized groups (p < 0.01 and p < 0.05 re-spectively). sIgA expression levels in the intestine decreased in the order of jejunum > duodenum > ileum.

3.4 | Effects of 7S and 11S on sIgA protein expression

Western blot results of sIgA protein expression are shown in Figure 6. Compared with those in control group, the sIgA protein

F IGURE  2 Histamine content in the small intestine of piglets (ng/ml). (a) control group; (b) 7S- sensitized group; (c) 11S- sensitized group; (d) 7S- injection immunized + sensitized group; (e) 11S- injection immunized + sensitized group; (f) 7S- orally immunized + sensitized group; (g) 11S- orally immunized + sensitized group. Comparison between different groups, the data with different superscripts of capital letters indicate significance at 0.01 level, the data with different superscripts of small letters indicate significance at 0.05 level, the data with the same superscripts letter or no superscripts means no significant difference at 0.05 level

     |  5PENG Et al.

levels in the intestines of piglets in sensitized groups were signifi-cantly increased (p < 0.01). sIgA protein levels in the intestines of piglets in immunized groups were significantly lower than those of piglets in sensitized groups (p < 0.05 and p < 0.01, respectively), and those of 7S- sensitized group were significantly higher than those of 11S- sensitized group (p < 0.05).

3.5 | Effects of 7S and 11S on relative IgA mRNA expression

Compared with control group, relative mRNA expression values of IgA in intestinal tissues of piglets in sensitized groups were sig-nificantly increased (p < 0.01 and p < 0.05 respectively). Moreover,

F IGURE  3 Secretory IgA expression in the duodenum of piglets. 10 × 40. (a) control group; (b) 7S- sensitized group; (c) 11S- sensitized group; (d) 7S- injection immunized + sensitized group; (e) 11S- injection immunized + sensitized group; (f) 7S- orally immunized + sensitized group; (g) 11S- orally immunized + sensitized group; NC: negative control

F IGURE  4 Secretory IgA expression in the jejunum of piglets. 10 × 40. (a) control group; (b) 7S- sensitized group; (c) 11S- sensitized group; (d) 7S- injection immunized + sensitized group; (e) 11S- injection immunized + sensitized group; (f) 7S- orally immunized + sensitized group; (g) 11S- orally immunized + sensitized group; NC: negative control

F IGURE  5 Secretory IgA expression in the ileum of piglets. 10 × 40. (a) control group; (b) 7S- sensitized group; (c) 11S- sensitized group; (d) 7S- injection immunized + sensitized group; (e) 11S- injection immunized + sensitized group; (f) 7S- orally immunized + sensitized group; (g) 11S- orally immunized + sensitized group; NC: negative control

6  |     PENG Et al.

compared with sensitized groups, relative IgA mRNA expression was significantly decreased in immunized groups (p < 0.05). Additionally, in the duodenums, relative mRNA expression of IgA was signifi-cantly higher in orally immunized groups than in injection immunized groups (p < 0.01).

4  | DISCUSSION

Soybean antigen protein leads to intestinal damage in piglets and other animals and has become a serious problem worldwide. Intracellular histamine levels can be used as an indicator of the

TABLE  2 Relative expression of intestinal mucosa IgA mRNA in piglets

Items A B C D E F G

Duodenum 1.00 ± 0.02C 2.88 ± 0.21Aa 1.81 ± 0.14Ba 2.18 ± 0.21D 1.11 ± 0.14Bc 2.62 ± 0.02Ab 1.51 ± 0.14Bb

Jejunum 1.00 ± 0.01Ca 3.15 ± 0.04Aa 2.01 ± 0.06Ba 2.15 ± 0.04D 1.31 ± 0.06Cb 2.88 ± 0.01Ab 1.71 ± 0.06Bb

Ileum 1.01 ± 0.15C 2.52 ± 0.18Aa 1.70 ± 0.02Ba 1.62 ± 0.18D 1.20 ± 0.02C 2.32 ± 0.15Ab 1.50 ± 0.02Bb

Note. A,B,C,DDifferent upper- case letters in a row represent significant differences (p < 0.01). a,b,c,dDifferent lower- case letters in a row represent significant differences (p < 0.05). Data are expressed as the mean ± SD.

F IGURE  6 Effects of 7S and 11S on the expression of sIgA protein in the small intestines of piglets. (a) control group; (b) 7S- sensitized group; (c) 11S- sensitized group; (d) 7S- injection immunized + sensitized group; (e) 11S- injection immunized + sensitized group; (f) 7S- orally immunized + sensitized group; (g) 11S- orally immunized + sensitized group. In comparisons between groups, data with different superscripted capital letters indicate significance at the 0.01 level, data with different superscripted lowercase letters indicate significance at the 0.05 level, and data with the same superscripted letters or no superscripts indicate no significant difference at the 0.05 level

     |  7PENG Et al.

sensitivity to histamine release, indicating that intracellular hista-mine levels are lower and that more histamine is released by pro-liferative mast cells, which participate in metabolism in the small intestine. The high level of histamine release may be another major response through which 7S and 11S induce immediate hypersensi-tivity (Liu, Jiang, & Liu, 2011; Shen et al., 2014; Sun et al., 2008). In the present study, after 7S or 11S sensitization, the histamine levels were significantly decreased in most parts of the intestine in pig-lets, indicating that histamine release was significantly increased, consistent with the findings of Sun et al. (2008). Excessive histamine release will promote the expansion and infiltration of local capillar-ies, resulting in absorption of soybean antigen proteins and causing damage to the intestine. The histamine content in the duodenum and ileum was significantly increased in piglets immunized in ad-vance, indicating that histamine release could be controlled by prior immunization. Additionally, the histamine content in the duodenum of piglets with 7S- or 11S- injection immunization was higher than that of piglets with 7S- or/11S- oral immunization, in the jejunum of piglets with 7S- injection immunization was higher than with 7S- oral immunization, and in the ileum of piglets with 11S- injection immuni-zation was higher than that with 11S- oral immunization, suggesting that the effects of injection immunization were observed prior to those of oral immunization with the same dose.

Wu, Cao, Ren et al. (2016) fed piglets a diet with 4% glycinin or β- conglycinin and found that soybean antigen proteins induce aller-gic reactions, damage the intestinal mucosa, increase intestinal per-meability, and promote sIgA synthesis in weaned piglets. Given the immunologic importance of IgA in immune surveillance in the intes-tine, the primary purpose of effective oral vaccines is the efficient induction of antigen- specific IgA responses (Kunisawa et al., 2014). Yang et al. (2018) immunized mice by the intraperitoneal and oral routeswithcelllysatesofrecombinantbaculovirusrBacmid-ORF2.The ELISA results for IgA response to swine hepatitis E virus indi-cated that immunization using the recombinant baculovirus could induce a humoral response via both routes.

Kunisawa et al. (2014) found that dietary palmitic acid and its metabolites play a critical role in the enhancement of intestinal IgA responses. sIgA plays a vital role in mucosal immunity and defends against a variety of pathogenic infections, including of bacteria, vi-ruses, and parasites. Furthermore, sIgA levels can reflect the body’s immune state (Michetti, Mahan, Slauch, Mekalonos, & Neutra, 1992; Rodrigues et al., 2000). In our experiment, immunohistochem-ical results revealed that after 7S or 11S sensitization, expression of sIgA was significantly increased in piglets compared with that in the control group. sIgA expression was significantly reduced in piglets immunized in advance, indicating that soybean antigen protein- immunizing agents reduced the immune response in piglets. Moreover, sIgA expression in piglets immunized orally was higher than that in piglets immunized by injection, suggesting that the ef-fects of injection immunization were more pronounced than those of oral immunization at the same dose. sIgA expression was higher in the jejunum than in other intestinal tissues, potentially because of the presence of plasma cells in the jejunum and the release of sIgA

from the glands. The expression of sIgA in this study was similar to that reported by Shen et al. (2014).

Western blot results revealed that sIgA protein expression levels in piglets immunized with 7S were significantly higher than those in piglets immunized with 11S, suggesting that the damage of 7S was higher than that of 11S, and sIgA protein expression levels were sig-nificantly decreased in piglets immunized in advance by 7S or 11S. Furthermore, the levels of sIgA protein expression in the intestines of piglets immunized orally were higher than those of piglets im-munized by injection, indicating that premature immunization had protective effects in piglets and that the effects of immunization by injection were better than those of oral immunization at the same dose.

The relative expression of IgA mRNA in piglets sensitized with 7S and 11S was higher than that in the control group, and the rela-tive expression of IgA mRNA was significantly reduced in piglets im-munized in advance. Furthermore, IgA relative mRNA expression in orally immunized piglets was higher than that in injection- immunized piglets administered the same dose. These results were consistent with the positive expression of sIgA.

5  | CONCLUSION

In summary, we found that pre- immunization with 7S and 11S re-duced the expression of IgA mRNA and sIgA protein and enhanced the content of histamine in intestine of piglets caused by 7S and 11S. Protective effects of immunization by injection were better than those of oral immunization at the same dose.

ACKNOWLEDG MENTS

This study was jointly supported by the National ‘Fu Min Qiang Xian’ Program of China [grant number 2012- 745] and the Project of Modern Agricultural Industry and Technology System of Anhui Province [grant number AHCYJSTX- 05/07].

ORCID

Xichun Wang https://orcid.org/0000-0001-5096-3970

Jinjie Wu https://orcid.org/0000-0001-9706-0808

REFERENCES

Catsimpoolas, N., & Ekenstam, C. (1969). Isolation of alpha, beta, and gamma conglycinins. Archives of Biochemistry and Biophysics, 129(2), 490–497. https://doi.org/10.1016/0003-9861(69)90206-9

Chen, F., Hao, Y., Piao, X. S., Ma, X., Wu, G. Y., Qiao, S. Y., … Wang, J. J. (2011). Soybean- derived beta- conglycinin affects proteome ex-pression in pig intestinal cells in vivo and in vitro. Journal of Animal Science, 89, 743–753. https://doi.org/10.2527/jas.2010-3146

Holzhauser,T.,Wackermann,O.,Ballmerweber,B.K.,Bindslevjensen,G.,Scibilia, J., Peronogaroffo, L., … Vieths, S. (2009). Soybean (Glycine max) allergy in Europe: Gly m 5 (β- conglycinin) and Gly m 6 (glycinin)

8  |     PENG Et al.

are potential diagnostic markers for severe allergic reactions to soy. The Journal of Allergy and Clinical Immunology, 123, 452. https://doi.org/10.1016/j.jaci.2008.09.034

Kunisawa, J., Hashimoto, E., Inoue, A., Nagasawa, R., Suzuki, Y., Ishikawa, I., … Kiyono, H. (2014). Regulation of intestinal IgA re-sponses by dietary palmitic acid and its metabolism. The Journal of Immunology, 193, 1666–1671. https://doi.org/10.4049/jimmunol.1302944

Lamichhane, A., Azegamia, T., & Kiyono, H. (2014). The mucosal im-mune system for vaccine development. Vaccine, 32(49), 6711–6723. https://doi.org/10.1016/j.vaccine.2014.08.089

Li, H., Zhu, K., Zhou, H., & Peng, W. (2012). Effects of high hydrostatic pressure treatment on allergenicity and structural properties of soy-bean protein isolate for infant formula. Food Chemistry, 132, 808–814. https://doi.org/10.1016/j.foodchem.2011.11.040

Liu, D. Y., Jiang, W., & Liu, P. (2011). Reduction of the amount of in-testinal secretory IgA in fulminant hepatic failure. The Brazilian Journal of Medical and Biological Research, 44, 477–482. https://doi.org/10.1590/S0100-879X2011007500051

Michetti, P., Mahan, M. J., Slauch, J. M., Mekalonos, J. J., & Neutra, M. R. (1992). Monoclonal secretory immunoglobulin A protects mice against oral challenge with the invasive pathogen Salmonella typh-imurium. Infection and Immunity, 60, 1786–1792.

National Research Council (1996). The National Science Education Standards [M]. Washington DC: National Academy Press, 1996, 23.

Peng, H., Shen, Y., Zhang, Q., Liu, J., Wang, Z., Huang, L., & Yu, Q. (2018). Qihuang decoction promotes the recovery of intestinal immune barrier dysfunction after gastrectomy in rats. American Journal of Translational Research, 10, 827–836.

Potts, R. A., Tiffany, C. M., Pakpour, N., Lokken, K. L., Tiffany, C. R., Cheung, K., … Luckhart, S. (2016). Mast cells and histamine alter intes-tinal permeability during malaria parasite infection. Immunobiology, 221, 468–474. https://doi.org/10.1016/j.imbio.2015.11.003

Rodrigues, A. C. P., Cara, D. C., Fretez, S. H. G. G., Cunha, F. Q., Vieira, E. C., Nicoli, J. R., & Vieira, L. Q. (2000). Saccharomyces boulardii stimulates sIgA production and the phagocytic system of gnotobi-otic mice. Journal of Applied Microbiology, 89, 404–414. https://doi.org/10.1046/j.1365-2672.2000.01128.x

SAS. (2002–2012). SAS/STAT 9.2 user’s guide. Cary, NC: SAS Institute Inc.Shen, J., Chen, Y., Wang, Z., Zhou, A., He, M., Mao, L., … Lv, Y. (2014).

Coated zinc oxide improves intestinal immunity function and regulates microbiota composition in weaned piglets. British Journal of Nutrition, 111, 2123–2134. https://doi.org/10.1017/S0007114514000300

Sun, P., Li, D., Li, Z., Dong, B., & Wang, F. (2008). Effects of glycinin on IgE- mediated increase of mast cell numbers and histamine release in

the small intestine. The Journal of Nutritional Biochemistry, 19, 627–633. https://doi.org/10.1016/j.jnutbio.2007.08.007

Sun, H., Liu, X., Wang, Y. Z., Liu, J. X., & Feng, J. (2013). Soybean glyci-nin- and β- conglycinin- induced intestinal immune responses in a mu-rine model of allergy. Food and Agricultural Immunology, 24, 357–369. https://doi.org/10.1080/09540105.2012.704507

Wang, T., Qin, G. X., Sun, Z. W., & Zhao, Y. (2014). Advances of research on glycinin and β- conglycinin: A review of two major soybean aller-genic proteins. Critical Reviews in Food Science and Nutrition, 54, 850–862. https://doi.org/10.1080/10408398.2011.613534

Wang, Y., Wang, Z., Handa, C. L., & Xu, J. (2017). Effects of ultrasound pre- treatment on the structure of β- conglycinin and glycinin and the antioxidant activity of their hydrolysates. Food Chemistry, 218, 165–172. https://doi.org/10.1016/j.foodchem.2016.09.069

Wu, J. J., Cao, C. M., Meng, T. T., Zhang, Y., Xu, S. L., Feng, S. B., … Wang, X. C. (2016). Induction of immune responses and allergic reactions in piglets by injecting glycinin. Italian Journal of Animal Science, 15, 166–173. https://doi.org/10.1080/1828051X.2016.1144488

Wu, J. J., Cao, C. M., Ren, D. D., Zhang, Y., Kou, Y. N., Ma, L. Y., … Wang, X. C. (2016). Effects of soybean antigen proteins on in-testinal permeability, 5- hydroxytryptamine levels and secretory IgA distribution in the intestine of weaned piglets. Italian Journal of Animal Science, 15, 174–180. https://doi.org/10.1080/1828051X.2016.1148559

Wu, J. J., Zhang, Y., Dong, J. H., Cao, C. M., Li, B., Feng, S. B., … Li, Y. (2016). Allergens and intestinal damage induced by soybean antigen proteins in weaned piglets. Italian Journal of Animal Science, 15, 437–445. https://doi.org/10.1080/1828051X.2016.1200441

Yang, Z., Hu, Y., Yuan, P., Yang, Y., Wang, K., Xie, L. Y., … Song, Z. H. (2018). Construction of a recombinant baculovirus expressing swine hepatitisEVirusORF2andpreliminaryresearchon its immuneef-fect. Polish Journal of Veterinary Sciences, 21(1), 47–54. https://doi.org/10.24425/119021

Zhao, Y., Qin, G., Han, R., Wang, J., Zhang, X., & Liu, D. (2014). β- conglycinin reduces the tight junction occludin and zo- 1 expression in ipec- j2. International Journal of Molecular Sciences, 15, 1915–1926. https://doi.org/10.3390/ijms15021915

How to cite this article: Peng C, Tang X, Shu Y, et al. Effects of 7S and 11S on the intestine of weaned piglets after injection and oral administration of soybean antigen protein. Anim Sci J. 2019;00:1–8. https://doi.org/10.1111/asj.13130

本文献由“学霸图书馆-文献云下载”收集自网络，仅供学习交流使用。

学霸图书馆（www.xuebalib.com）是一个“整合众多图书馆数据库资源，

提供一站式文献检索和下载服务”的24 小时在线不限IP

图书馆。

图书馆致力于便利、促进学习与科研，提供最强文献下载服务。

图书馆导航：

图书馆首页 文献云下载 图书馆入口 外文数据库大全 疑难文献辅助工具