Synergism between Ecologic and Immunologic Control Mechanisms of Intestinal Flora

Shedlofsky, Steve; Freter, Rolf

doi:10.1093/infdis/129.3.296

Cited by 65 publications

(22 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This can be inferred from analogy with Escherichia coli and Streptococcus faecalis (4). Growth of Vibrio cholerae was reported to be suppressed by synergism between local antibacte-rial immunity and the intestinal flora (8). The nul+ mice in our study most likely suppressed the growth of P. aeruginosa in their intestines with the aid of the intestinal flora in addition to the T-cell-dependent immune system.…”

supporting

confidence: 51%

Liability of the Athymic Nude Mouse to Intestinal Colonization by Pseudomonas aeruginosa

Morishita

Nagasawa

Aibara

1982

Microbiology and Immunology

View full text Add to dashboard Cite

Brown and Balish (1) reported that there were no marked differences in the gastrointestinal flora between BALBjc athymic nude (nujnu) mice and their heterozygous (nuj +) littermates. Investigating the intestinal flora of BALBjc nujnu mice and their nuj + littermates, however, we found that although there were no significant differences in the indigenous flora of the intestine between them, nujnu mice showed a remarkably high incidence of spontaneous colonization by Pseudomonas aeruginosa in their small intestines (91 % of 11 animals tested) and feces (100% of 13 animals) as compared with nuj+ mice (0% of 14 and 47% of 15, respectively) .The high incidence of P. aeruginosa colonization in the nujnu mice we observed might be due to a lack of a thymus-dependent immune system (6). Therefore, to confirm this finding nujnu mice were compared with their nuj + littermates with respect to intestinal colonization by P. aeruginosa administered orally.BALBjc nujnu mice and their nuj + littermates (6 to 10 weeks old) were used.They were produced in our laboratory by mating nude (nujnu) males and heterozygous (nuj +) females. The nujnu and nuj + mice were separately housed in metal cages with filter caps (Sanki Kagaku Kogei Co.) and kept on a rack with a laminar air filter unit (Sanki Kagaku Kogei Co.). They were given a 3-Mradirradiated diet (MB-3, Funabashi Nojyo) and given fresh tap water each day with the exception of the time of the administration of a P. aeruginosa culture. Cages and bedding were sterilized at 160 C for an hour.For administration of P. aeruginosa, animals were given drinking water containing, per ml, approximately 1 X 10 6 viable cells of P. aeruginosa grown overnight in brain heart infusion broth (Difco Laboratories). The drinking water bottles were autoclaved after two days of feeding. Feces and intestines with their contents, as bacteriological samples, were aseptically collected, weighed, homogenized, and diluted serially 10-fold in phosphate-buffered solution (pH 7.2). NAC agar (Eiken Chemical Co.) was used for enumeration of P. aeruginosa. P. aeruginosa strains were serologically identified with antisera obtained from Denka Seiken Co. Bacteria other than P. aeruginosa were not counted, because there would be no significant difference in their counts between the nujnu and nuj + mice as we found on preliminary examination.

show abstract

supporting

confidence: 51%

Liability of the Athymic Nude Mouse to Intestinal Colonization by Pseudomonas aeruginosa

Morishita

Nagasawa

Aibara

1982

Microbiology and Immunology

View full text Add to dashboard Cite

show abstract

“…Finally, it should be mentioned that these two mechanisms that con trol the microecology of the upper respiratory tract may actually be synergistic. This has been suggested by Fretcr [39] in the gastrointestinal tract where it has been shown that vaccination which produces local immunity and the installation of interfering bacterial organisms together had a greater role on inhibiting the survival of Vibrio cholerae than each mechanism alone. Whether or not this synergism plays a role in the upper respiratory tract flora has not yet been determined.…”

Section: The Nasal Mucosa As An Immunocompetent Tissuementioning

confidence: 89%

Mucosal Immunology of the Upper Respiratory Tract

Bernstein

1992

Respiration

View full text Add to dashboard Cite

The palatine tonsils and nasopharyngeal adenoids represent the predominant immunocompetent tissue of the upper respiratory tract. Its major function is as a first line of defense against viral, bacterial, and food antigens that enter the upper aerodigestive system. Another major function of the tonsils and adenoids is to supply the local mucosal immune system of the upper respiratory tract with dimeric IgA-producing B cells. Secretory IgA has particular hydrophilic properties and is capable of preventing adsorption and penetration of bacteria and/or viruses into the upper respiratory tract mucosa. In addition, the role of the indigenous flora of the upper respiratory tract, particularly the viridans streptococci has been emphasized as providing a valuable source of bacterial interference to the colonization of potential pathogens.

show abstract

“…These interactions begin when the microbiota develop during succession in the neonate and continue throughout life (1). Local antibacterial immunity may act synergistically with bacterial antagonism in controlling bacterial populations in the intestine (30). Conversely, indigenous microbiota play an important role in the development and maintenance of the normal steady state of GALT (3).…”

Section: Discussionmentioning

confidence: 99%

Timing, Localization, and Persistence of Colonization by Segmented Filamentous Bacteria in the Neonatal Mouse Gut Depend on Immune Status of Mothers and Pups

2001

View full text Add to dashboard Cite

As a member of the indigenous gut mucosal microbiota, segmented filamentous bacteria (SFB) colonize the guts of a variety of vertebrates and invertebrates. They are potent microbial stimuli of the gut mucosal immune system. In the small intestines of mice and rats, it has been observed that SFB are absent during the suckling period and appear in high numbers shortly after weaning, then quickly retreat to the cecum and large intestine. In this study, we explored whether this microecological phenomenon resulted from the interaction between SFB and the passively acquired maternal mucosal immunity and/or the actively acquired mucosal immunity. We set up a mouse model by reciprocal crossings and backcrossings of SFB-monoassociated, formerly germ-free, immunocompetent (؉/؉) BALB/c mice and immunodeficient (scid/scid) mice to produce pups which are either immunocompetent (scid/؉) or immunodeficient (scid/scid) and are born either to immunocompetent (scid/؉) mothers or to immunodeficient (scid/scid) mothers. We monitored the number of SFB on the mucosa of the small intestine in the four different groups of mice after birth, as well as the level of passively acquired antibodies, the active gut mucosal immune responses, and immunoglobulin A (IgA) coating of SFB in the gut. The results showed that, irrespective of whether the pups were scid/scid or scid/؉, SFB could be found earlier on the mucosa of the small intestine in pups born to scid/scid mothers, appearing from day 13 and rapidly reaching a climax around weaning time on day 28, compared to the significantly delayed colonization in the pups of scid/؉ mothers, starting from day 16 and peaking around days 28 to 32. After the climax, SFB quickly declined to very low levels in the small intestines of scid/؉ pups of either scid/scid mothers or scid/؉ mothers, whereas they remained at high levels in scid/scid pups at least until day 70, the last observation time in this study. The dynamic changes in SFB colonization of the small intestines of the different groups of pups may be related to the dynamic changes in the levels of SFB coated with secretory IgA (sIgA), which resulted from the significantly different levels of sIgA obtained from the mothers' milk during the suckling period and, later, of self-produced sIgA in the small intestine. Nevertheless, it is evident that the timing, localization, and persistence of colonization of the neonatal gut by SFB depends on the immune status of both mothers and pups.The intestinal tracts of animals and humans are heavily colonized by gut microbiota. Gut-associated lymphoid tissue (GALT), which generates strong mucosal immune responses against the invasion of frank pathogens, seems to have evolved to permit the survival and propagation of the indigenous microbial populations in the gut (29). On the other hand, GALT in conventional animals is in a physiologically activated state (4, 36), in sharp contrast to the quiescent state of GALT in germ-free (GF) animals. Little is known about the mechanisms of the interactions between indigen...

show abstract

Synergism between Ecologic and Immunologic Control Mechanisms of Intestinal Flora

Cited by 65 publications

References 18 publications

Liability of the Athymic Nude Mouse to Intestinal Colonization by Pseudomonas aeruginosa

Liability of the Athymic Nude Mouse to Intestinal Colonization by Pseudomonas aeruginosa

Mucosal Immunology of the Upper Respiratory Tract

Timing, Localization, and Persistence of Colonization by Segmented Filamentous Bacteria in the Neonatal Mouse Gut Depend on Immune Status of Mothers and Pups

Contact Info

Product

Resources

About