Whole tissue homogenization preferable to mucosal scraping in determining the temporal profile of segmented filamentous bacteria in the ileum of weanling rats

Segmented filamentous bacteria (SFB) are thought to play a role in small intestine immunological maturation. Studies in weanling mice have shown a positive correlation between ileal SFB abundance and plasma and faecal interleukin 17 (IL-17) and immunoglobulin A (IgA) concentrations. Although the first observation of SFB presence was reported in rats, most studies use mice. The size of the mouse ileum is a limitation whereas the rat could be a suitable alternative for sufficient samples. Changes in SFB abundance over time in rats were hypothesized to follow the pattern reported in mice and infants. We characterized the profile of SFB colonization in the ileum tissue and contents and its correlation with two immune markers of gastrointestinal tract (GIT) maturation. We also compared two published ileum collection techniques to determine which yields data on SFB abundance with least variability. Whole ileal tissue and ileal mucosal scrapings were collected from 20- to 32-day-old Sprague-Dawley rats. SFB abundance was quantified from proximal, middle and distal ileal tissues, contents and faeces by quantitative PCR using SFB-specific primers. Antibody-specific ELISAs were used to determine IL-17 and IgA concentrations. Significant differences in SFB abundance were observed from whole and scraped tissues peaking at day 22. Variability in whole ileum data was less, favouring it as a better collection technique. A similar pattern of SFB abundance was observed in ileum contents and faeces peaking at day 24, suggesting faeces can be a proxy for ileal SFB abundance. SFB abundance at day 26 was higher in females than males across all samples. There were significant differences in IgA concentration between days 20, 30 and 32 and none in IL-17 concentration, which was different from reports in mice and infants.

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The Role of Segmented Filamentous Bacteria in Immune Barrier Maturation of the Small Intestine at Weaning

Frontiers in Nutrition ◽

10.3389/fnut.2021.759137 ◽

2021 ◽

Vol 8 ◽

Author(s):

Linda A. Oemcke ◽

Rachel C. Anderson ◽

Eric Altermann ◽

Nicole C. Roy ◽

Warren C. McNabb

Keyword(s):

Small Intestine ◽

Current Knowledge ◽

Immunoglobulin A ◽

Interleukin 17 ◽

Filamentous Bacteria ◽

Segmented Filamentous Bacteria ◽

Stool Samples ◽

Food Substrate ◽

Immunological Barrier

The microbiological, physical, chemical, and immunological barriers of the gastrointestinal tract (GIT) begin developing in utero and finish maturing postnatally. Maturation of these barriers is essential for the proper functioning of the GIT. Maturation, particularly of the immunological barrier, involves stimulation by bacteria. Segmented filamentous bacteria (SFB) which are anaerobic, spore-forming commensals have been linked to immune activation. The presence and changes in SFB abundance have been positively correlated to immune markers (cytokines and immunoglobulins) in the rat ileum and stool samples, pre- and post-weaning. The abundance of SFB in infant stool increases from 6 months, peaks around 12 months and plateaus 25 months post-weaning. Changes in SFB abundance at these times correlate positively and negatively with the production of interleukin 17 (IL 17) and immunoglobulin A (IgA), respectively, indicating involvement in immune function and maturation. Additionally, the peak in SFB abundance when a human milk diet was complemented by solid foods hints at a diet effect. SFB genome analysis revealed enzymes involved in metabolic pathways for survival, growth and development, host mucosal attachment and substrate acquisition. This narrative review discusses the current knowledge of SFB and their suggested effects on the small intestine immune system. Referencing the published genomes of rat and mouse SFB, the use of food substrates to modulate SFB abundance is proposed while considering their effects on other microbes. Changes in the immune response caused by the interaction of food substrate with SFB may provide insight into their role in infant immunological barrier maturation.

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Segmented Filamentous Bacteria Are Potent Stimuli of a Physiologically Normal State of the Murine Gut Mucosal Immune System

Infection and Immunity ◽

10.1128/iai.67.4.1992-2000.1999 ◽

1999 ◽

Vol 67 (4) ◽

pp. 1992-2000 ◽

Cited By ~ 241

Author(s):

Gwen L. Talham ◽

Han-Qing Jiang ◽

Nicolaas A. Bos ◽

John J. Cebra

Keyword(s):

T Cells ◽

Immune System ◽

Immunoglobulin A ◽

Mucosal Immune System ◽

Filamentous Bacteria ◽

Mesenteric Lymph Nodes ◽

Segmented Filamentous Bacteria ◽

Iga Antibody ◽

Autochthonous Bacteria ◽

Iga Production

ABSTRACT Segmented filamentous bacteria (SFB) are autochthonous bacteria inhabiting the intestinal tracts of many species, including humans. We studied the effect of SFB on the mucosal immune system by monoassociating formerly germfree C3H/HeN mice with SFB. At various time points during 190 days of colonization, fragment cultures of small intestine and Peyer’s patches (PP) were analyzed for total immunoglobulin A (IgA) and SFB-specific IgA production. Also, phenotypic changes indicating germinal center reactions (GCRs) and the activation of CD4+ T cells in PP were determined by using fluorescence-activated cell sorter analyses. A second group of SFB-monoassociated mice was colonized with a gram-negative commensal,Morganella morganii, to determine if the mucosal immune system was again stimulated and to evaluate the effect of prior colonization with SFB on the ability of M. morganii to translocate to the spleen and mesenteric lymph nodes. We found that SFB stimulated GCRs in PP from day 6 after monoassociation, that GCRs only gradually waned over the entire length of colonization, that natural IgA production was increased to levels 24 to 63% of that of conventionally reared mice, and that SFB-specific IgA was produced but accounted for less than 1.4% of total IgA. Also, the proportion of CD4+, CD45RBlow T cells, indicative of activated cells, gradually increased in the PP to the level found in conventionally reared mice. Secondary colonization with M. morganii was able to stimulate GCRs anew, leading to a specific IgA antibody response. Previous stimulation of mucosal immunity by SFB did not prevent the translocation of M. morganii in the double-colonized mice. Our findings generally indicate that SFB are one of the single most potent microbial stimuli of the gut mucosal immune system.

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The Effect of Endurance Training and Saffron Extract on Plasma Levels of Interleukin 17 and 18 in Alzheimer’s Rats by Trimethyltin Chloride

Complementary Medicine Journal ◽

10.32598/cmja.10.2.896.2 ◽

2020 ◽

Vol 10 (2) ◽

pp. 148-159

Author(s):

Fatemeh Tahvili ◽

◽

Mozhgan Ahmadi ◽

Keyword(s):

Experimental Study ◽

Exercise Training ◽

Endurance Training ◽

Plasma Levels ◽

Interleukin 17 ◽

Interleukin 18 ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Saffron Extract ◽

Trimethyltin Chloride

Objective: The Pathological symptoms of Alzheimer’s disease and the degeneration of nerve cells cause inflammation in these patients. This study aimed to investigate the effect of endurance training and saffron extract on the plasma levels of interleukin 17 and 18 in Alzheimer’s rats by trimethyltin chloride. Methods: This experimental study was conducted on 32 male Sprague-Dawley rats weighing 180 ± 20 grams. After Alzheimer’s induction (by the intraperitoneal injection of 80 mg/kg trimethyltin chloride), the rats were randomly assigned into four groups: control, training, saffron extract, saffron extract + training. The saffron extract was injected intraperitoneally at the dose of 25 mg/kg, daily, for eight weeks. Also, the endurance training program consisted of incremental running on the treadmill at a speed of 15 to 20 m/min. The program was performed in 15 to 30 minutes sessions, three sessions per week, for eight weeks. Finally, the obtained data were analyzed using two-way ANOVA at the P < 0.05. Results: The results showed that exercise (P=0.10), saffron consumption (P=0.07), and the interaction of exercise and saffron consumption (P=0.06) did not significantly affect interleukin 17, in rats. Also, exercise (P=0.68), saffron consumption (P=0.84), and the interaction of exercise and saffron consumption (P=0.57) had no significant effect on interleukin 18, in rats. Conclusion: According to the results, it seems that exercise training and saffron extract do not affect the interleukin 17 and interleukin 18 in Alzheimer’s rats.

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Facilitated Intranasal Induction of Mucosal and Systemic Immunity to Mutans Streptococcal Glucosyltransferase Peptide Vaccines

Infection and Immunity ◽

10.1128/iai.69.8.4767-4773.2001 ◽

2001 ◽

Vol 69 (8) ◽

pp. 4767-4773 ◽

Cited By ~ 19

Author(s):

Daniel J. Smith ◽

William F. King ◽

Leigh A. Barnes ◽

Debra Trantolo ◽

Donald L. Wise ◽

...

Keyword(s):

Intranasal Administration ◽

Immunoglobulin A ◽

Enzyme Linked Immunosorbent Assay ◽

Peptide Vaccines ◽

Sprague Dawley ◽

Igg Antibody ◽

Serum Igg ◽

Mucosal Antibody ◽

Sprague Dawley Rats ◽

Plga Microparticles

ABSTRACT Synthetic peptide vaccines which are derived from functional domains of Streptococcus mutans glucosyltransferases (GTF) have been shown to induce protective immunity in Sprague-Dawley rats after subcutaneous injection in the salivary gland region. Since mucosal induction of salivary immunity would be preferable in humans, we explored methods to induce mucosal antibody in the rat to the GTF peptide vaccines HDS and HDS-GLU after intranasal administration. Several methods of facilitation of the immune response were studied: the incorporation of peptides in bioadhesive poly(d,l-lactide-coglycolide) (PLGA) microparticles, the use of monoepitopic (HDS) or diepitopic (HDS-GLU) peptide constructs, or the use of mucosal adjuvants. Salivary immunoglobulin A (IgA) responses were not detected after intranasal administration of diepitopic HDS-GLU peptide constructs in alum or after incorporation into PLGA microparticles. However, significant primary and secondary salivary IgA and serum IgG antibody responses to HDS were induced in all rats when cholera holotoxin (CT) or a detoxified mutant Escherichia coli heat-labile enterotoxin (R192G LT) were intranasally administered with HDS peptide constructs in PLGA. Coadministration of LT with HDS resulted in predominantly IgG2a responses in the serum, while coadministration with CT resulted in significant IgG1 and IgG2a responses to HDS. Serum IgG antibody, which was induced to the HDS peptide construct by coadministration with these adjuvants, also bound intact mutans streptococcal GTF in an enzyme-linked immunosorbent assay and inhibited its enzymatic activity. Thus, immune responses which are potentially protective for dental caries can be induced to peptide-based GTF vaccines after mucosal administration if combined with the CT or LT R192G mucosal adjuvant.

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Potency of Lactobacillus plantarum Dad-13 and Sweet Potato (Ipomoea batatas) Fiber as Immunomodulator in Rats Infected With Salmonella Typhimurium

Journal of Food Research ◽

10.5539/jfr.v4n3p1 ◽

2015 ◽

Vol 4 (3) ◽

pp. 1 ◽

Cited By ~ 1

Author(s):

. Nurliyani ◽

Madarina Julia ◽

Eni Harmayani ◽

Muthi Ikawati ◽

Endang Baliarti

Keyword(s):

Lactobacillus Plantarum ◽

Sweet Potato ◽

Ipomoea Batatas ◽

Immunoglobulin A ◽

Fermented Milk ◽

Mucosal Immune Response ◽

Soluble Fiber ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Secretory Immunoglobulin

Lactobacillus plantarum Dad-13 that isolated from “dadih” (traditional Indonesian fermented milk) has been known as probiotic, while sweet potato fiber has been proven as an effective prebiotic. The objective of this study was to evaluate the potency of Lactobacillus plantarum Dad-13 and sweet potato fiber as immunomodulators in terms of intestinal secretory immunoglobulin A (sIgA) and splenocyte gamma-interferon (IFN-?). Sixty male Sprague Dawley rats (uninfected and infected) were divided into five groups: AIN-93, Indonesian children diet (ICD), Sweet potato fiber (SPF), SPF + Lactobacillus plantarum Dad-13 (SPFL), and fructooligosaccharides + Lacto-B (FOSL). After diet intervention, the rats were killed and sampled including intestinal fluid, spleen and caecal digesta. The results showed that soluble fiber such as sweet potato fiber could not increase the number of lactobacilli in infected rats, but could play a role in mucosal immune response through the increasing of sIgA. While, Lactobacillus plantarum Dad-13 contained in the combination with sweet potato fiber may has potency in systemic immune stimulation, because of the tendency to increase level of splenocyte IFN-? in infected rats.

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Spontaneous glomerular immunoglobulin deposition in young Sprague-Dawley rats

Laboratory Animals ◽

10.1258/002367788780746232 ◽

1988 ◽

Vol 22 (4) ◽

pp. 287-292 ◽

Cited By ~ 6

Author(s):

N. P. Goode ◽

A. M. Davison ◽

G. Gowland ◽

M. Shires

Keyword(s):

Immune Complexes ◽

Age Group ◽

Newborn Rats ◽

Sprague Dawley ◽

Sprague Dawley Rats ◽

Weanling Rats ◽

Dense Deposits ◽

High Concentrations ◽

Igm Deposits ◽

Maternal Igg

The frequency, age-onset and distribution of spontaneously deposited immunoglobulins (lgs) in glomeruli of Sprague-Dawley rats has been investigated. Groups of rats ( n=10) were examined at 4-7 day intervals from birth (presuckling) until 30 days of age. Findings were compared with circulating immunoglobulin concentrations in each age group. Immunoglobulins were undetectable in immature kidneys of newborn rats. However, as early as 5 days, scanty IgA and IgM deposits were observed predominantly in mesangial areas of mature glomeruli, corresponding to low circulating concentrations of these immunoglobulins. By contrast, glomerular IgG deposits were not observed until 21 days, despite relatively high concentrations of circulating maternal IgG from birth. Mesangial deposition of immunoglobulins increased with age. Absence of complement C3c or electron dense deposits associated with this mesangial localization suggests that immunoglobulins were not deposited as immune complexes. Accumulation of non-phlogogenic immunoglobulins in the mesangium of normal rats supports the concept that the mesangium is constantly perfused by circulating macro-molecules and filtration residues. The results indicate problems of interpretation of the significance of endogenous immunoglobulin deposition in models of experimental glomerulonephritis, even in studies involving weanling rats.

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Quantification of antigen-specific immunoglobulin A after oral booster immunization with ovalbumin in mice mono-associated with segmented filamentous bacteria or Clostridium innocuum

Immunology Letters ◽

10.1016/s0165-2478(97)02715-6 ◽

1997 ◽

Vol 58 (1) ◽

pp. 25-28 ◽

Cited By ~ 10

Author(s):

J Snel ◽

M.H Bakker ◽

P.J Heidt

Keyword(s):

Immunoglobulin A ◽

Filamentous Bacteria ◽

Booster Immunization ◽

Segmented Filamentous Bacteria ◽

Specific Immunoglobulin

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Differential Roles of Segmented Filamentous Bacteria and Clostridia in Development of the Intestinal Immune System

Infection and Immunity ◽

10.1128/iai.67.7.3504-3511.1999 ◽

1999 ◽

Vol 67 (7) ◽

pp. 3504-3511 ◽

Cited By ~ 169

Author(s):

Yoshinori Umesaki ◽

Hiromi Setoyama ◽

Satoshi Matsumoto ◽

Akemi Imaoka ◽

Kikuji Itoh

Keyword(s):

Small Intestine ◽

Immune System ◽

Large Intestine ◽

Immunoglobulin A ◽

Cell Receptor ◽

Intraepithelial Lymphocytes ◽

Filamentous Bacteria ◽

Segmented Filamentous Bacteria ◽

Intestinal Immune System ◽

Gnotobiotic Mice

ABSTRACT The presence of microflora in the digestive tract promotes the development of the intestinal immune system. In this study, to evaluate the roles of two types of indigenous microbe, segmented filamentous bacteria (SFB) and clostridia, whose habitats are the small and large intestines, respectively, in this immunological development, we analyzed three kinds of gnotobiotic mice contaminated with SFB, clostridia, and both SFB and clostridia, respectively, in comparison with germfree (GF) or conventionalized (Cvd) mice associated with specific-pathogen-free flora. In the small intestine, the number of αβ T-cell receptor-bearing intraepithelial lymphocytes (αβIEL) increased in SFB-associated mice (SFB-mice) but not in clostridium-associated mice (Clost-mice). There was no great difference in Vβ usage among GF mice, Cvd mice, and these gnotobiotic mice, although the association with SFB decreased the proportion of Vβ6+ cells in CD8β− subsets to some extent, compared to that in GF mice. The expression of major histocompatibility complex class II molecules on the epithelial cells was observed in SFB-mice but not in Clost-mice. On the other hand, in the large intestine, the ratio of the number of CD4−CD8+ cells to that of CD4+ CD8−cells in αβIEL increased in Clost-mice but not in SFB-mice. On association with both SFB and clostridia, the numbers and phenotypes of IEL in the small and large intestines changed to become similar to those in Cvd mice. In particular, the ratio of the number of CD8αβ+ cells to that of CD8αα+ cells in αβIEL, unusually elevated in the small intestines of SFB-mice, decreased to the level in Cvd mice on contamination with both SFB and clostridia. The number of immunoglobulin A (IgA)-producing cells in the lamina propria was more elevated in SFB-mice than in Clost-mice, not only in the ileum but also in the colon. The number of IgA-producing cells in the colons of Clost-mice was a little increased compared to that in GF mice. Taken together, SFB and clostridia promoted the development of both IEL and IgA-producing cells in the small intestine and that of only IEL in the large intestine, respectively, suggesting the occurrence of compartmentalization of the immunological responses to the indigenous bacteria between the small and large intestines.

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