Fibrinogen binds to nontoxigenic and toxigenic Corynebacterium diphtheriae strains.
The production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. Although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (Fbn)-binding properties of Corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. In this study we demonstrated the ability of C. diphtheriae strains to bind to Fbn and to convert Fbn to fibrin. Bacterial interaction with rabbit plasma was evaluated by both slide and tube tests. Interaction of microorganisms with human Fbn was evaluated by both enzyme linked immunosorbent assay (ELISA) and fluorescein isothiocyanate-conjugated (FITC) Fbn binding assays. Nontoxigenic and toxigenic strains formed bacterial aggregates in the presence of plasma in the slide tests. The ability to convert Fbn to a loose web of fibrin in the plasma solution in the tube tests appeared to be a common characteristic of the species, including strains that do not carry the tox gene. Fbn binding to C. diphtheriae strains occurred at varying intensities, as demonstrated by the FITC-Fbn and ELISA binding assays. Our data suggest that the capacity to bind to Fbn and to convert Fbn to fibrin may play a role in pseudomembrane formation and act as virulence determinants of both nontoxigenic and toxigenic strains.
Sabbadini
Priscila Soares
PS
Laboratório de Difteria e Corineformes de Importância Médica, Faculdade de Medicina, Universidade do Estado do Rio de Janeiro, 20551-030 Rio de Janeiro, Brasil.
Genovez
Marcia Rocha Novais
MR
Silva
Cecília Ferreira da
CF
Adelino
Thelma Lúcia Novaes
TL
Santos
Cintia Silva dos
CS
Pereira
Gabriela Andrade
GA
Nagao
Prescilla Emy
PE
Dias
Alexandre Alves de Souza de Oliveira
AA
Mattos-Guaraldi
Ana Luiza
AL
Hirata Júnior
Raphael
R
D000818:Animals; D003353:Corynebacterium diphtheriae / Q000235:genetics / Q000378:metabolism*; D004167:Diphtheria Toxin / Q000235:genetics / Q000378:metabolism*; D004797:Enzyme-Linked Immunosorbent Assay; D005340:Fibrinogen / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D011817:Rabbits; D014774:Virulence / Q000235:genetics
D004167:Diphtheria Toxin; D005340:Fibrinogen