Limits...
Competition of Lactobacillus paracasei with Salmonella enterica for adhesion to Caco-2 cells.

Jankowska A, Laubitz D, Antushevich H, Zabielski R, Grzesiuk E - J. Biomed. Biotechnol. (2008)

Bottom Line: Caco-2 cells were grown for 6 or 21 days to obtain nondifferentiated or well-differentiated cells, respectively.Both bacterial strains used adhered better to well-differentiated than to nondifferentiated Caco-2 cells, however, the amount of Salmonella adhered to Caco-2 after 2 hours of contact was 12-fold higher in comparison to L. paracasei and almost 27-fold higher after 4 hours of contact.In conclusion, the displacement of pathogens by lactic acid bacteria and its secretions showed here depends on the time of bacteria-epithelial cell contact, and also on the stage of Caco-2 differentiation.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Molecular Biology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland.

ABSTRACT
Competition of commensal and probiotic bacteria with pathogens for adhesion and colonization is one of the important protective mechanisms of gastrointestinal tract. In this study, we examined the ability of Lactobacillus paracasei to inhibit the adhesion of pathogenic Salmonella enterica to human colon adenocarcinoma Caco-2 cells. Caco-2 cells were grown for 6 or 21 days to obtain nondifferentiated or well-differentiated cells, respectively. In adhesion experiments, bacteria were added to the cells for 2 or 4 hours. The number of attached bacteria was expressed as colony-forming units (CFUs), Caco-2 cells were counted in hematocytometer. Both bacterial strains used adhered better to well-differentiated than to nondifferentiated Caco-2 cells, however, the amount of Salmonella adhered to Caco-2 after 2 hours of contact was 12-fold higher in comparison to L. paracasei and almost 27-fold higher after 4 hours of contact. Two types of experiments were done: coincubation (both bacteria were added to Caco-2 cells simultaneously), and preincubation (L. paracasei was incubated with Caco-2 cells first, and then S. enterica was added). In coincubation experiment, the presence of L. paracasei decreased S. enterica adhesion by 4-fold and in preincubation experiment even 7-fold. Generally, Lactobacillus spent culture supernatants (SCSs) acted weaker as inhibitors of Salmonella adhesion in comparison to the whole L. paracasei culture in coincubation experiment. In conclusion, the displacement of pathogens by lactic acid bacteria and its secretions showed here depends on the time of bacteria-epithelial cell contact, and also on the stage of Caco-2 differentiation.

Show MeSH

Related in: MedlinePlus

Adhesion of (a) L. paracasei and (b) S. enterica to nondifferentiated and well-differentiated Caco-2 cells in 2- and 4-hour experiments. Mean and SEM, t-test. Asterisks indicate the statistical differences: *P < .05, **P < .01, ***P < .001.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC2279207&req=5

fig1: Adhesion of (a) L. paracasei and (b) S. enterica to nondifferentiated and well-differentiated Caco-2 cells in 2- and 4-hour experiments. Mean and SEM, t-test. Asterisks indicate the statistical differences: *P < .05, **P < .01, ***P < .001.

Mentions: We studied the adhesion of five LAB strains (three Lactobacillus and two Lactococcus). These bacteria adhered to Caco-2 cells in the range of 0.5 to 5 bacteria per one cell. The adherence of L. paracasei to Caco-2 cells was low (Figure 1(a)). Only 0.6 bacteria adhered to one nondifferentiated (growing for 6 days) Caco-2 cells, and about 1.5 bacteria adhered to well-differentiated (growing for 21 days) cells. There was no significant difference between 2- and 4-hour incubation of L. pracasei with Caco-2. For competition experiments, the L. paracasei was selected since among all LAB strains tested L. paracasei was the only one adhering better to well-differentiated than to nondifferentiatedCaco-2 cells exactly as pathogenic S. enterica. The adherence of S. enterica (Figure 1(b)) was high as compared to that of L. pracasei (P < .01). On the average, there were 6 and 25 bacteria per nondifferentiated Caco-2 cells after 2- and 4-hour incubation, respectively, and 18 and 40 bacteria perdifferentiated Caco-2 cells after 2- and 4-hour incubation, respectively (Figure 1(b)). Thus, the rule, the longer the contact the higher adhesion rate, was true for S. enterica but not for L. pracasei.


Competition of Lactobacillus paracasei with Salmonella enterica for adhesion to Caco-2 cells.

Jankowska A, Laubitz D, Antushevich H, Zabielski R, Grzesiuk E - J. Biomed. Biotechnol. (2008)

Adhesion of (a) L. paracasei and (b) S. enterica to nondifferentiated and well-differentiated Caco-2 cells in 2- and 4-hour experiments. Mean and SEM, t-test. Asterisks indicate the statistical differences: *P < .05, **P < .01, ***P < .001.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2279207&req=5

fig1: Adhesion of (a) L. paracasei and (b) S. enterica to nondifferentiated and well-differentiated Caco-2 cells in 2- and 4-hour experiments. Mean and SEM, t-test. Asterisks indicate the statistical differences: *P < .05, **P < .01, ***P < .001.
Mentions: We studied the adhesion of five LAB strains (three Lactobacillus and two Lactococcus). These bacteria adhered to Caco-2 cells in the range of 0.5 to 5 bacteria per one cell. The adherence of L. paracasei to Caco-2 cells was low (Figure 1(a)). Only 0.6 bacteria adhered to one nondifferentiated (growing for 6 days) Caco-2 cells, and about 1.5 bacteria adhered to well-differentiated (growing for 21 days) cells. There was no significant difference between 2- and 4-hour incubation of L. pracasei with Caco-2. For competition experiments, the L. paracasei was selected since among all LAB strains tested L. paracasei was the only one adhering better to well-differentiated than to nondifferentiatedCaco-2 cells exactly as pathogenic S. enterica. The adherence of S. enterica (Figure 1(b)) was high as compared to that of L. pracasei (P < .01). On the average, there were 6 and 25 bacteria per nondifferentiated Caco-2 cells after 2- and 4-hour incubation, respectively, and 18 and 40 bacteria perdifferentiated Caco-2 cells after 2- and 4-hour incubation, respectively (Figure 1(b)). Thus, the rule, the longer the contact the higher adhesion rate, was true for S. enterica but not for L. pracasei.

Bottom Line: Caco-2 cells were grown for 6 or 21 days to obtain nondifferentiated or well-differentiated cells, respectively.Both bacterial strains used adhered better to well-differentiated than to nondifferentiated Caco-2 cells, however, the amount of Salmonella adhered to Caco-2 after 2 hours of contact was 12-fold higher in comparison to L. paracasei and almost 27-fold higher after 4 hours of contact.In conclusion, the displacement of pathogens by lactic acid bacteria and its secretions showed here depends on the time of bacteria-epithelial cell contact, and also on the stage of Caco-2 differentiation.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Molecular Biology, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences, Instytucka 3, 05-110 Jabłonna, Poland.

ABSTRACT
Competition of commensal and probiotic bacteria with pathogens for adhesion and colonization is one of the important protective mechanisms of gastrointestinal tract. In this study, we examined the ability of Lactobacillus paracasei to inhibit the adhesion of pathogenic Salmonella enterica to human colon adenocarcinoma Caco-2 cells. Caco-2 cells were grown for 6 or 21 days to obtain nondifferentiated or well-differentiated cells, respectively. In adhesion experiments, bacteria were added to the cells for 2 or 4 hours. The number of attached bacteria was expressed as colony-forming units (CFUs), Caco-2 cells were counted in hematocytometer. Both bacterial strains used adhered better to well-differentiated than to nondifferentiated Caco-2 cells, however, the amount of Salmonella adhered to Caco-2 after 2 hours of contact was 12-fold higher in comparison to L. paracasei and almost 27-fold higher after 4 hours of contact. Two types of experiments were done: coincubation (both bacteria were added to Caco-2 cells simultaneously), and preincubation (L. paracasei was incubated with Caco-2 cells first, and then S. enterica was added). In coincubation experiment, the presence of L. paracasei decreased S. enterica adhesion by 4-fold and in preincubation experiment even 7-fold. Generally, Lactobacillus spent culture supernatants (SCSs) acted weaker as inhibitors of Salmonella adhesion in comparison to the whole L. paracasei culture in coincubation experiment. In conclusion, the displacement of pathogens by lactic acid bacteria and its secretions showed here depends on the time of bacteria-epithelial cell contact, and also on the stage of Caco-2 differentiation.

Show MeSH
Related in: MedlinePlus