Adherence of Borrelia burgdorferi to the proteoglycan decorin

Abstract

Lyme disease is a tick-borne infection that can develop into a chronic, multisystemic disorder. The causative agent, Borrelia burgdorferi, is initially deposited by the tick into the host dermis, where it associates with collagen fibers, replicates, and eventually disseminates to other tissues. We have examined the adherence of the spirochete to different components of the collagen fiber and demonstrated that decorin, a proteoglycan which decorates collagen fibers, can support the attachment of B. burgdorferi. No significant direct attachment to isolated type I or III collagens could be detected. Attachment of the spirochetes to decorin was highly specific, and the process could be inhibited by soluble decorin but not by various unlabeled, unrelated components. B. burgdorferi also bound soluble 125 I-labeled decorin in a time-and concentration-dependent manner. Spirochete binding of soluble 125 I-labeled decorin required intact proteoglycan and could not be inhibited by either isolated core protein or glycosaminoglycan chain. B. burgdorferi expresses two decorin-binding proteins with apparent molecular masses of 19 and 20 kDa as revealed in a Western blot (immunoblot)-type assay. Our results indicate that decorin may mediate the adherence of B. burgdorferi to collagen fibers in skin and other tissues.

Characterization of a candidate Borrelia burgdorferiβ3‐chain integrin ligand identified using a phage display library

“…Of course, additional adhesins participate in the attachment of pathogenic bacteria to mammalian cells and tissues. B. burgdorferi, for example, expresses the lipoprotein adhesins decorin-binding protein (Guo et al, 1995;1998) and fibronectin-binding protein (Probert and Johnson, 1998). A candidate B. burgdorferi ligand for heparan and dermatan sulphate has been identified recently (N. Parveen and J. M. Leong, unpublished). B. burgdorferi p66 does not contain any consensus integrin recognition motifs, but the same is true of invasin, the Yersinia protein that binds with high affinity to several ␤ 1 -chain integrins Leong et al, 1990).…”

Decorin‐binding adhesins from Borrelia burgdorferi

“…We used a microtitre well attachment assay to study the adherence of B. burgdorferi to decorin. Initial experiments showed that strain N40 (Guo et al, 1995) could adhere to decorin-coated microtitre wells. The effects of purified, recombinant Dbps or OspC on bacterial adherence were examined in experiments in which decorin-coated wells were preincubated with increasing concentrations of recombinant Borrelia proteins for 1 h before whole B. burgdorferi cells were added.…”

A comparative analysis of the attachment ofLeptospira interrogansandL. borgpeterseniito mammalian cells

“…The following shows the changes made to the established attachment assay of Guo et al (1995). Microtitre plates were coated overnight at 4°C with 100 lL of a 0.5, 1 and 10 lg mL À1 solution of human fibronectin (R&D Systems).…”