Limits...
Borrelia valaisiana resist complement-mediated killing independently of the recruitment of immune regulators and inactivation of complement components.

Schwab J, Hammerschmidt C, Richter D, Skerka C, Matuschka FR, Wallich R, Zipfel PF, Kraiczy P - PLoS ONE (2013)

Bottom Line: Among the investigated isolates, growth of ZWU3 Ny3 was not affected while growth of VS116 and Bv9 was strongly inhibited in the presence of 50% human serum.In contrast, no surface-deposited components and no aberrations in cell morphology were detected for serum-resistant ZWU3 Ny3.Taken together, these findings suggest that certain B. valaisiana isolates differ in their capability to resist complement-mediating killing by human serum.

View Article: PubMed Central - PubMed

Affiliation: Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Frankfurt, Germany.

ABSTRACT
Spirochetes belonging to the Borrelia (B.) burgdorferi sensu lato complex differ in their resistance to complement-mediated killing, particularly in regard to human serum. In the present study, we elucidate the serum and complement susceptibility of B. valaisiana, a genospecies with the potential to cause Lyme disease in Europe as well as in Asia. Among the investigated isolates, growth of ZWU3 Ny3 was not affected while growth of VS116 and Bv9 was strongly inhibited in the presence of 50% human serum. Analyzing complement activation, complement components C3, C4 and C6 were deposited on the surface of isolates VS116 and Bv9, and similarly the membrane attack complex was formed on their surface. In contrast, no surface-deposited components and no aberrations in cell morphology were detected for serum-resistant ZWU3 Ny3. While further investigating the protective role of bound complement regulators in mediating complement resistance, we discovered that none of the B. valaisiana isolates analyzed bound complement regulators Factor H, Factor H-like protein 1, C4b binding protein or C1 esterase inhibitor. In addition, B. valaisiana also lacked intrinsic proteolytic activity to degrade complement components C3, C3b, C4, C4b, and C5. Taken together, these findings suggest that certain B. valaisiana isolates differ in their capability to resist complement-mediating killing by human serum. The molecular mechanism utilized by B. valaisiana to inhibit bacteriolysis appears not to involve binding of the key host complement regulators of the alternative, classical, and lectin pathways as already known for serum-resistant Lyme disease or relapsing fever borreliae.

Show MeSH

Related in: MedlinePlus

Determination of the C3a generation by B. valaisiana.Spirochetes (6×106) were incubated with 25% of NHS for 5 min at 21°C and activation of C3 was then analyzed by the MicroVue C3a Plus ELISA. Generated C3a was detected using a monoclonal anti-C3a capture antibody and a HRP-conjugated polyclonal anti-C3 antiserum. All experiments were performed three times with at least three replicates, obtaining very similar results. For clarity, data of a representative experiment are shown. Error bars represent ± SD. Raw data were analyzed by one-way ANOVA with post hoc Bonferroni correction. ***p<0.001; *p<0.05.
© Copyright Policy
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3539980&req=5

pone-0053659-g008: Determination of the C3a generation by B. valaisiana.Spirochetes (6×106) were incubated with 25% of NHS for 5 min at 21°C and activation of C3 was then analyzed by the MicroVue C3a Plus ELISA. Generated C3a was detected using a monoclonal anti-C3a capture antibody and a HRP-conjugated polyclonal anti-C3 antiserum. All experiments were performed three times with at least three replicates, obtaining very similar results. For clarity, data of a representative experiment are shown. Error bars represent ± SD. Raw data were analyzed by one-way ANOVA with post hoc Bonferroni correction. ***p<0.001; *p<0.05.

Mentions: To further evaluate the ability of serum-resistant B. burgdorferi LW2 and B. valaisiana ZWU3 Ny3 to inhibit complement activation at the level of C3 and C4 we sought to quantify the generation of C3a and C4a after incubation of spirochetes with human serum by ELISA. As demonstrated in figure 8, C3 activation was significantly reduced for B. burgdorferi LW2 (p-value <0.001) as well as for B. valaisiana ZWU3 Ny3 (p-value 0.05) while, in contrast, a stronger C3a generation could be detected for serum-sensitive B. garinii G1 as well as B. valaisiana Bv9 and VS116. Of note, pre-incubation of NHS for 5 min at 21°C resulted in a somewhat higher C3a generation compared to untreated NHS samples. Nevertheless, the data collected support the notion that ZWU3 Ny3 inhibits C3 activation to some extent.


Borrelia valaisiana resist complement-mediated killing independently of the recruitment of immune regulators and inactivation of complement components.

Schwab J, Hammerschmidt C, Richter D, Skerka C, Matuschka FR, Wallich R, Zipfel PF, Kraiczy P - PLoS ONE (2013)

Determination of the C3a generation by B. valaisiana.Spirochetes (6×106) were incubated with 25% of NHS for 5 min at 21°C and activation of C3 was then analyzed by the MicroVue C3a Plus ELISA. Generated C3a was detected using a monoclonal anti-C3a capture antibody and a HRP-conjugated polyclonal anti-C3 antiserum. All experiments were performed three times with at least three replicates, obtaining very similar results. For clarity, data of a representative experiment are shown. Error bars represent ± SD. Raw data were analyzed by one-way ANOVA with post hoc Bonferroni correction. ***p<0.001; *p<0.05.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3539980&req=5

pone-0053659-g008: Determination of the C3a generation by B. valaisiana.Spirochetes (6×106) were incubated with 25% of NHS for 5 min at 21°C and activation of C3 was then analyzed by the MicroVue C3a Plus ELISA. Generated C3a was detected using a monoclonal anti-C3a capture antibody and a HRP-conjugated polyclonal anti-C3 antiserum. All experiments were performed three times with at least three replicates, obtaining very similar results. For clarity, data of a representative experiment are shown. Error bars represent ± SD. Raw data were analyzed by one-way ANOVA with post hoc Bonferroni correction. ***p<0.001; *p<0.05.
Mentions: To further evaluate the ability of serum-resistant B. burgdorferi LW2 and B. valaisiana ZWU3 Ny3 to inhibit complement activation at the level of C3 and C4 we sought to quantify the generation of C3a and C4a after incubation of spirochetes with human serum by ELISA. As demonstrated in figure 8, C3 activation was significantly reduced for B. burgdorferi LW2 (p-value <0.001) as well as for B. valaisiana ZWU3 Ny3 (p-value 0.05) while, in contrast, a stronger C3a generation could be detected for serum-sensitive B. garinii G1 as well as B. valaisiana Bv9 and VS116. Of note, pre-incubation of NHS for 5 min at 21°C resulted in a somewhat higher C3a generation compared to untreated NHS samples. Nevertheless, the data collected support the notion that ZWU3 Ny3 inhibits C3 activation to some extent.

Bottom Line: Among the investigated isolates, growth of ZWU3 Ny3 was not affected while growth of VS116 and Bv9 was strongly inhibited in the presence of 50% human serum.In contrast, no surface-deposited components and no aberrations in cell morphology were detected for serum-resistant ZWU3 Ny3.Taken together, these findings suggest that certain B. valaisiana isolates differ in their capability to resist complement-mediating killing by human serum.

View Article: PubMed Central - PubMed

Affiliation: Institute of Medical Microbiology and Infection Control, University Hospital of Frankfurt, Frankfurt, Germany.

ABSTRACT
Spirochetes belonging to the Borrelia (B.) burgdorferi sensu lato complex differ in their resistance to complement-mediated killing, particularly in regard to human serum. In the present study, we elucidate the serum and complement susceptibility of B. valaisiana, a genospecies with the potential to cause Lyme disease in Europe as well as in Asia. Among the investigated isolates, growth of ZWU3 Ny3 was not affected while growth of VS116 and Bv9 was strongly inhibited in the presence of 50% human serum. Analyzing complement activation, complement components C3, C4 and C6 were deposited on the surface of isolates VS116 and Bv9, and similarly the membrane attack complex was formed on their surface. In contrast, no surface-deposited components and no aberrations in cell morphology were detected for serum-resistant ZWU3 Ny3. While further investigating the protective role of bound complement regulators in mediating complement resistance, we discovered that none of the B. valaisiana isolates analyzed bound complement regulators Factor H, Factor H-like protein 1, C4b binding protein or C1 esterase inhibitor. In addition, B. valaisiana also lacked intrinsic proteolytic activity to degrade complement components C3, C3b, C4, C4b, and C5. Taken together, these findings suggest that certain B. valaisiana isolates differ in their capability to resist complement-mediating killing by human serum. The molecular mechanism utilized by B. valaisiana to inhibit bacteriolysis appears not to involve binding of the key host complement regulators of the alternative, classical, and lectin pathways as already known for serum-resistant Lyme disease or relapsing fever borreliae.

Show MeSH
Related in: MedlinePlus