Attachment of Neisseria meningitidis to Human Mucosal Surfaces: Influence of Pili and Type of Receptor Cell

Abstract

The factors that determine attachment of meningococci predominantly to the mucosa of the nasopharynx rather than to other mucosal surfaces are unknown. Isolates of Neisseria meningitidis from the nasopharynx of carriers and from patients with meningococcal disease were found to be heavily piliated. Isogenic piliated and nonpiliated meningococcal clones were derived from blood and cerebrospinal fluid isolates. Meningococci with pili consistently attached to human nasopharyngeal cells in greater numbers than meningococci without pili. Meningococci treated with trypsin or mechanical shear forces lost pili and exhibited decreased attachment. Attachment of piliated meningococci differed markedly among epithelial cells from different sites. In contrast, nonpiliated meningococci attached equally but in low numbers to all cell types. These data suggest that pili are important mediators of meningococcal attachment. The number and distribution of receptor sites for pili or pili-associated meningococcal ligands differ among human cells and may determine sites of meningococcal colonization.

Correlation between Branhamella catarrhalis adherence to oropharyngeal cells and seasonal incidence of lower respiratory tract infections.

“…On the other hand, neither the duration nor the severity of the underlying disease was significantly associated with an increased rate of adherence. The investigations focused on bacterial determinant of adherence indicated that serial sub-cultures lead to damage of the bacterial pili (De Voe and Gilchrist 1975) which are thought to be involved in attachment (Buchnan and Pearce 1976;Beachey 1981;Stephens and McGee 1981). In the present study, this possibility could be excluded, because the fresh isolates were stored in separate tubes of which one each was used for one experiment alone.…”

“…The basic method of in vitro adherence assay performed in this study is a modification of that of Stephens and McGee (1981) used in their recent work.…”

Identification of Epitopes Recognized by Monoclonal Antibodies SM1 and SM2 Which React with All Pili of Neisseria gonorrhoeae but Which Differentiate between Two Structural Classes of Pili Expressed by Neisseria meningitidis and the Distribution of Their Encoding Sequences in the Genomes of Neisseria spp.

“…Many studies have subsequently reported that the association between pilus expression and virulence results from the ability of pili to facilitate adhesion of gonococci to the mucosal surfaces of the genital tract, the essential first stage in pathogenesis of gonococcal infection (reviewed by Heckels, 1989). Although the association of piliation with meningococcal disease is less well established, fresh meningococcal isolates from both blood and cerebrospinal fluid are invariably piliated, and pili facilitate adhesion of meningococci to nasopharyngeal cells in D i m , suggesting that they play an important role in colonization of the mucosal surfaces of the nasopharynx (Stephens & McGee, 1981;Trust et al, 1983).…”

Meningococcal disease: -- A review based on a symposium held on 11 July 1992 at the Liverpool School of Tropical Medicine

“…meningitidis is composed of various biologically active molecules, many of which are highly variable, most notably, OMP I1 (opacity 34-36 and pili (fimbriae).34,37*38 Pili are important adhesins in meningococci and isolates from patients are almost invariably pilate when observed microscopically. Pilation appears to be required for colonisation of host mucosal surfaces and for at least some stages of invasive disease caused by these bacteria.37, 39-43 Pili are filamentous protein appendages which extend considerable distances from the bacterial surface and are probably responsible for initial interaction with host epithelial cells and subsequently with endothelial cells.5, [42][43][44] Pili produced by pathogenic Neisseria spp. are composed of repeated subunits of pilin polypeptide with approximately 10 000 pilin subunits assembled to form an individual Meningococci have been observed to produce either one of two types of pilus, class I and class I1 (table II).576344346-52 Class I pili are The 53 N-terminal amino acids of mature pilin are conserved between antigenically distinct molecules constituting the conserved (C) region.…”