Study of Cell Migration in Intraperitoneal Infection by Escherichia coli in Mice Swiss
-
1
Centro Universitário Filadélfia UNIFIL, Biomedicina, Brazil
-
2
Universidade Estadual de Londrina, Microbiologia, Brazil
Escherichia coli (E. coli) is present in the gut of humans, in addition to being in the microbiota of healthy individuals, however when its presence is associated with immunosuppressed individuals or even when occurs a violation barriers present in the gastrointestinal tract, not pathogenic strains can cause infection and damage to the same. These strains may be limited to the mucosal surface or spread by the body of individuals.
E. coli has an uncanny ability to adapt to different environments and also by present particular characteristics regarding pathogenicity mechanisms. Some varieties of E. coli are linked directly to infectious diseases in humans and can cause intestinal and extraintestinal infections. As a result of these actions, the individual can trigger pathogenic clinical syndromes such as urinary tract infection, meningitis in newborn, sepsis and diarrhea. The conserved feature of strains of E. coli diarrheogenic (DEC) is the ability to colonize the surface of the intestinal mucosa in spite of peristalsis and the competition for nutrients in the intestinal flora.
The inflammation caused by E. coli leads to a displacement of cells like leukocytes and plasma molecules to the site where infection is occurring, and can be noted as main effects of this inflammation is associated with the blood supply, leading to an increase in vascular permeability to serum molecules of large size, besides favoring the migration of leukocytes by local vascular endothelium, and for the location of the inflammatory process.
The present work was performed at the Filadelfia University Center (UniFil), Londrina-PR, Brazil, research laboratory of biomedical and Clinical Pathology Laboratory of the Veterinary Hospital of Filadelfia University Center and had as main objective to evaluate the cell migration in Swiss mice infected experimentally via intraperitoneal by different variety of E. coli.
64 female SWISS mice were used with age between 8 and 10 weeks from the Maringá State University. The animals were kept at a temperature of 22° C +/ -2° C, and were divided into 4 groups (mice infected by E. coli enterohemorrhagic (EHEC-EDL 993), E. coli enteroinvasive (EIEC EDL – 1284), E. coli (ATCC 25922) and a negative control without bacteria. The use of animals has fulfilled the standards established by the Animal Brazilian College experimentation, and the experimental protocol was approved by the Ethics Committee on Animal experimentation the Filadelfia University Center (protocol number 001/2014). The groups were conducted in quadruplicate, and repeated in two independent experiments.
A suspension containing 1 x 10^5 CFU/ml of E. coli (EHEC, EIEC, ATCC) were inoculated intraperitoneally into a single dose in certain groups. After periods of zero (control), 30 minutes, 3, 6, 12 and 24 h inoculation of bacteria. For obtaining peritoneal exudate were inoculated 4 mL of intraperitoneal saline solution.
Reading the leukocytes of samples from the exudates of mice were evaluated through the Veterinary Hospital Hematology reader of UniFil, showing the amount of lymphocytes, monocytes and granulocytes.
The results may show that the migration of leukocytes to the peritoneal cavity comes to occur differently among the strains studied front to infection with E. coli. It was observed that the amount of leukocytes present in the peritoneal cavity of infected animals by EHEC strains and had a significant higher EIEC those of standard strains ATCC.
Animals infected with the standard strain showed an increase in the number of leucocytes in peritoneal cavity, where it reached its peak in 12h after infection (4 x 10^3 ), and declined from 12h (3, 3 x 10^3), i.e. with the cell migration leukocytes recruited affecting on microorganism disposal studied, what didn't happen with virulent strains. In animals infected with EHEC and EIEC numbers of leukocytes in the peritoneal cavity reached the maximum after 12h the infection (6,37x10^3; 9,57x10^3; p < 0.001).
E. coli infection (EHEC) presents a potential virulence superior when compared to E. coli enteroinvasive (EIEC), causing the death of the objects under study, due to the presence of Shiga-like toxins I and II. However, in this study, it was observed that the amount of leukocytes present in the peritoneal cavity of animals which were infected with EIEC strains showed a superiority in amount occurring in animals infected with EHEC, due to the place where it was inoculated. As the inoculation was carried out by the intraperitoneal route, EIEC, for being invasive, succeeded in their invasion to the cells of the intestinal mucosa and come to cause injury to the same.
When we compare the lymphocytes recruited to the peritoneal cavity, one realizes that this high recruitment comes to start significantly after 6h of infection, which indicates that the adaptive immune response of animals came to act later than this time, aiming to combat infection caused by this microorganism.
However, the amount of monocytes and granulocytes present in intraperitoneal cavity of animals which were infected with EHEC strains and EIEC remained in constant growth to spend the hours of infection. Indicating a high and constant infection caused by the same. The adaptive response of animals began after the 6h of infection, but this infection had not yet ceased until the 12h
After the completion of this study it can be concluded that the amount of defense cells that have migrated to the peritoneum of the infected animals by EIEC strains and were significantly larger EHEC, when compared with the amount that migrated to the peritoneum of animals infected by the ATCC strains. And thus, prove that virulence patterns of bacteria studied have a profile of different immune system defense, showing the effectiveness of recruitment to the various molecular patterns associated with pathogens.
Acknowledgements
Financial Support: Centro Universitário Filadélfia, Fundação Araucária.
Keywords:
Escherichia coli,
cell migration,
Immunity and Infections,
innate immune response,
Leukocytes
Conference:
IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología, Medellin, Colombia, 13 Oct - 16 Oct, 2015.
Presentation Type:
Poster Presentation
Topic:
Innate Immunity
Citation:
Romero
RT,
Dos Santos
TS,
De Mato
FP,
Franciosi
A,
Campois
NF,
Sarmiento
JP,
Nakazato
G,
Gualtieri
KD and
Campois
TG
(2015). Study of Cell Migration in Intraperitoneal Infection by Escherichia coli in Mice Swiss.
Front. Immunol.
Conference Abstract:
IMMUNOCOLOMBIA2015 - 11th Congress of the Latin American Association of Immunology - 10o. Congreso de la Asociación Colombiana de Alergia, Asma e Inmunología.
doi: 10.3389/conf.fimmu.2015.05.00024
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
15 Apr 2015;
Published Online:
14 Sep 2015.
*
Correspondence:
Dr. Tacito G Campois, Centro Universitário Filadélfia UNIFIL, Biomedicina, Londrina, Brazil, tacito@biologo.bio.br