Coassociation between Group B Streptococcus and Candida albicans Promotes Interactions with Vaginal Epithelium.

Group B Streptococcus (GBS) is a leading cause of neonatal sepsis, pneumonia, and meningitis worldwide. In the majority of cases, GBS is transmitted vertically from mother to neonate, making maternal vaginal colonization a key risk factor for neonatal disease. The fungus Candida albicans is an opportunistic pathogen of the female genitourinary tract and the causative agent of vaginal thrush. Carriage of C. albicans has been shown to be an independent risk factor for vaginal colonization by GBS. However, the nature of interactions between these two microbes is poorly understood. This study provides evidence of a reciprocal, synergistic interplay between GBS and C. albicans that may serve to promote their cocolonization of the vaginal mucosa. GBS strains NEM316 (serotype III) and 515 (serotype Ia) are shown to physically interact with C. albicans, with the bacteria exhibiting tropism for candidal hyphal filaments. This interaction enhances association levels of both microbes with the vaginal epithelial cell line VK2/E6E7. The ability of GBS to coassociate with C. albicans is dependent upon expression of the hypha-specific adhesin Als3. In turn, expression of GBS antigen I/II family adhesins (Bsp polypeptides) facilitates this coassociation and confers upon surrogate Lactococcus lactis the capacity to exhibit enhanced interactions with C. albicans on vaginal epithelium. As genitourinary tract colonization is an essential first step in the pathogenesis of GBS and C. albicans, the coassociation mechanism reported here may have important implications for the risk of disease involving both of these pathogens.

Pidwill GR ，Rego S ，Jenkinson HF ，Lamont RJ ，Nobbs AH ... -  《-》

The Fungal Pathogen Candida albicans Promotes Bladder Colonization of Group B Streptococcus.

Group B Streptococcus (GBS) is a common cause of bacterial urinary tract infections (UTI) in susceptible populations, including pregnant women and the elderly. However, the factors that govern GBS persistence and disease severity in this niche are not fully understood. Here, we report that the presence of the fungus Candida albicans, a common urogenital colonizer, can promote GBS UTI. Co-inoculation of GBS with C. albicans increased bacterial adherence to bladder epithelium and promoted GBS colonization in vivo in a C. albicans adhesin-dependent manner. This study demonstrates that fungal colonization of the urogenital tract may be an important determinant of bacterial pathogenesis during UTI.

Shing SR ，Ramos AR ，Patras KA ，Riestra AM ，McCabe S ，Nizet V ，Coady A ... -  《-》

The Group B Streptococcal Adhesin BspC Interacts with Host Cytokeratin 19 To Promote Colonization of the Female Reproductive Tract.

Manzer HS ，Nguyen DT ，Park JY ，Park N ，Seo KS ，Thornton JA ，Nobbs AH ，Doran KS ... -  《mBio》

Group B Streptococcus CAMP Factor Does Not Contribute to Interactions with the Vaginal Epithelium and Is Dispensable for Vaginal Colonization in Mice.

Ballard MB ，Mercado-Evans V ，Marunde MG ，Nwanosike H ，Zulk J ，Patras KA ... -  《Microbiology Spectrum》

A Multi-Country Cross-Sectional Study of Vaginal Carriage of Group B Streptococci (GBS) and Escherichia coli in Resource-Poor Settings: Prevalences and Risk Factors.

Cools P ，Jespers V ，Hardy L ，Crucitti T ，Delany-Moretlwe S ，Mwaura M ，Ndayisaba GF ，van de Wijgert JH ，Vaneechoutte M ... -  《-》