» Articles » PMID: 6759406

Sensitivity of K1-encapsulated Escherichia Coli to Killing by the Bactericidal/permeability-increasing Protein of Rabbit and Human Neutrophils

Overview
Journal Infect Immun
Date 1982 Dec 1
PMID 6759406
Citations 18
Authors
Affiliations
Soon will be listed here.
Abstract

The presence of K1 capsular polysaccharides increases the resistance of Escherichia coli to killing by serum and phagocytosis by polymorphonuclear leukocytes (PMNs). To determine whether K1 capsule impedes the action of intracellular bactericidal systems of PMNs, we compared the sensitivity of several K1-encapsulated and non-encapsulated strains of E. coli to killing by the bactericidal/permeability-increasing protein (BPI) isolated from rabbit and human PMNs. BPI appears to be the principal bactericidal agent of PMNs toward E. coli and other gram-negative bacteria (Weiss et al., J. Clin. Invest. 69:959-970, 1982). The presence of K1 capsule was monitored by sensitivity to K1-specific bacteriophages. The non-encapsulated strains used represent both random bacteremic isolates and non-encapsulated derivatives of K1-encapsulated strains obtained by selection for resistance to K1-specific phages. We found little or no difference in the sensitivity of K1-encapsulated and non-encapsulated E. coli to killing by neutralized acid extracts of rabbit PMNs. Bacterial killing by these crude fractions can be attributed to the action of BPI because: (i) bacterial killing was blocked by immune (anti-BPI) immunoglobulin but not by preimmune immunoglobulin and (ii) comparison of the dose-response curves of bacterial killing by crude extracts and by purified BPI showed that the bactericidal activity of crude fractions corresponded closely to the BPI content. Human and rabbit BPIs exhibited similar bactericidal potency toward K1-encapsulated E. coli; i.e., <5 mug of either protein killed >90% of 2.5 x 10(7) bacteria. Thus, the potent bactericidal action of BPI toward E. coli is not impeded by K1 capsule, suggesting that the virulence of K1-encapsulated E. coli is a consequence of extracellular survival but not of resistance to intracellular killing.

Citing Articles

A live attenuated vaccine to prevent severe neonatal Escherichia coli K1 infections.

Sereme Y, Schrimp C, Faury H, Agapoff M, Lefebvre-Wloszczowski E, Chang Marchand Y Nat Commun. 2024; 15(1):3021.

PMID: 38589401 PMC: 11001983. DOI: 10.1038/s41467-024-46775-x.


Evolutionary and functional history of the Escherichia coli K1 capsule.

Arredondo-Alonso S, Blundell-Hunter G, Fu Z, Gladstone R, Fillol-Salom A, Loraine J Nat Commun. 2023; 14(1):3294.

PMID: 37322051 PMC: 10272209. DOI: 10.1038/s41467-023-39052-w.


Phenotypic Heterogeneity in Expression of the K1 Polysaccharide Capsule of Uropathogenic Escherichia coli and Downregulation of the Capsule Genes during Growth in Urine.

King J, Aal Owaif H, Jia J, Roberts I Infect Immun. 2015; 83(7):2605-13.

PMID: 25870229 PMC: 4468546. DOI: 10.1128/IAI.00188-15.


Mechanisms of polymyxin resistance: acquired and intrinsic resistance in bacteria.

Olaitan A, Morand S, Rolain J Front Microbiol. 2014; 5:643.

PMID: 25505462 PMC: 4244539. DOI: 10.3389/fmicb.2014.00643.


Role of capsule and O antigen in the virulence of uropathogenic Escherichia coli.

Sarkar S, Ulett G, Totsika M, Phan M, Schembri M PLoS One. 2014; 9(4):e94786.

PMID: 24722484 PMC: 3983267. DOI: 10.1371/journal.pone.0094786.


References
1.
Mancini G, Carbonara A, Heremans J . Immunochemical quantitation of antigens by single radial immunodiffusion. Immunochemistry. 1965; 2(3):235-54. DOI: 10.1016/0019-2791(65)90004-2. View

2.
Wilkinson R, GEMSKI Jr P, Stocker B . Non-smooth mutants of Salmonella typhimurium: differentiation by phage sensitivity and genetic mapping. J Gen Microbiol. 1972; 70(3):527-54. DOI: 10.1099/00221287-70-3-527. View

3.
Stendahl O, Edebo L . Phagocytosis of mutants of Salmonella typhimurium by rabbit polymorphonuclear cells. Acta Pathol Microbiol Scand B Microbiol Immunol. 1972; 80(4):481-8. DOI: 10.1111/j.1699-0463.1972.tb00169.x. View

4.
Kaijser B . Immunology of Escherichia coli: K antigen and its relation to urinary-tract infection. J Infect Dis. 1973; 127(6):670-7. DOI: 10.1093/infdis/127.6.670. View

5.
Robbins J, McCracken Jr G, Gotschlich E, ORSKOV F, ORSKOV I, Hanson L . Escherichia coli K1 capsular polysaccharide associated with neonatal meningitis. N Engl J Med. 1974; 290(22):1216-20. DOI: 10.1056/NEJM197405302902202. View