Comparison of adherence to and penetration of a human laryngeal epithelial cell line by group A streptococci of various M protein types

Abstract

Clinically isolated group A streptococci (GAS) of different M protein types were studied using aminoglycoside exclusion and [2,8-3H]adenine radiolabeled GAS assays to compare the abilities of different strains to adhere to and internalize within human laryngeal epithelial (HEp-2) cells. GAS isolated from patients with pharyngitis and GAS isolated from patients with more severe disease, such as necrotizing fasciitis, adhered to and penetrated HEp-2 cells equally well. M3, M4, M6, and M12 strains adhered to and were internalized within HEp-2 cells more than M1 strains. M18 GAS producing hyaluronic acid capsules were less adherent and less invasive than the M3, M4, M6, and M12 strains. An M3-producing GAS strain and its M protein-deficient isogenic strain adhered similarly to HEp-2 cells, but the M protein-deficient strain exhibited greater penetration. Preincubation of HEp-2 cells with an N-terminal synthetic M3 peptide did not alter the adherence or penetration by an M3 strain. In summary, this study demonstrates that GAS from invasive and non-invasive disease adhere to and penetrate HEp-2 cells equally well and that multiple strains of GAS with various M protein types have the ability to adhere to and penetrate HEp-2 cells.

Detection of Genes Encoding Internalization-Associated Proteins in Streptococcus pyogenes Isolates from Patients with Invasive Diseases and Asymptomatic Carriers

“…Although once considered to be an extracellular pathogen, S. pyogenes has been shown to be able to invade epithelial cells and survive for a limited time (2,23). The ability of S. pyogenes to invade epithelial cells has been suggested to be a trait connected to the propensity of strains to cause invasive infections (22), although more recent studies have either demonstrated the opposite (i.e., efficiency to penetrate cells is more pronounced among isolates from noninvasive infections) (13,17,23) or observed no differences between strains from various sources of isolation (16).…”

Insight into the molecular basis of pathogen abundance: Group AStreptococcusinhibitor of complement inhibits bacterial adherence and internalization into human cells

“…This gene also was absent in serotype M3 and M18 organisms that commonly cause human infections. In addition, Hagman et al (22) found that several M1 strains adhered minimally to human laryngeal epithelial cells. Gene expression analysis indicates that sic is maximally expressed in very early log phase (data not shown), suggesting that it acts during initial host-pathogen interactions.…”

Expression of the Biofilm-Associated Protein Interferes with Host Protein Receptors of Staphylococcus aureus and Alters the Infective Process

“…Similar phenomena occur with other pathogenic bacteria, such as Staphylococcus epidermidis (1), Streptococcus pneumoniae (42), group A streptococci (16), Klebsiella pneumoniae (11), Neisseria meningitidis (40), Escherichia coli (34), and Haemophilus influenzae type b (41). Similarly, we have observed in a mouse foreign-body infection model that a Bap-deficient mutant colonized a catheter more rapidly at the initial stages of infection than the wild-type bacteria, strongly suggesting that the presence of Bap might hinder the interaction between bacterial cell receptors and the host proteins on the catheter (7).…”