Binding of Elementary Bodies by the Opportunistic Fungal Pathogen Candida albicans or Soluble β-Glucan, Laminarin, Inhibits Chlamydia trachomatis Infectivity

Abstract

Microbial interactions represent an understudied facet of human health and disease. In this study, the interactions that occur between Chlamydia trachomatis and the opportunistic fungal pathogen, Candida albicans were investigated. Candida albicans is a common component of the oral and vaginal microbiota responsible for thrush and vaginal yeast infections. Normally, Candida exist in the body as yeast. However, disruptions to the microbiota create conditions that allow expanded growth of Candida, conversion to the hyphal form, and tissue invasion. Previous studies have shown that a myriad of outcomes can occur when Candida albicans interacts with pathogenic bacteria. To determine if C. trachomatis physically interacts with C. albicans, we incubated chlamydial elementary bodies (EB) in medium alone or with C. albicans yeast or hyphal forms for 1 h. Following incubation, the samples were formaldehyde-fixed and processed for immunofluorescence assays using anti-chlamydial MOMP or anti- chlamydial LPS antibodies. Replicate samples were replenished with culture medium and incubated at 35°C for 0–120 h prior to fixation for immunofluorescence analysis or collection for EB infectivity assays. Data from this study indicates that both C. trachomatis serovar E and C. muridarum EB bind to C. albicans yeast and hyphal forms. This interaction was not blocked by pre-incubation of EB with the Candida cell wall components, mannan or β-glucans, suggesting that EB interact with a Candida cell wall protein or other structure. Bound EB remained attached to C. albicans for a minimum of 5 days (120 h). Infectivity assays demonstrated that EB bound to C. albicans are infectious immediately following binding (0h). However, once bound to C. albicans, EB infectivity decreased at a faster rate than EB in medium alone. At 6h post binding, 40% of EB incubated in medium alone remained infectious compared to only 16% of EB bound to C. albicans. Likewise, pre-incubation of EB with laminarin, a soluble preparation of β-glucan, alone or in combination with other fungal cell wall components significantly decreases chlamydial infectivity in HeLa cells. These data indicate that interactions between EB and C. albicans inhibit chlamydial infectivity, possibly by physically blocking EB interactions with host cell receptors.

Monitoring Sexually Transmitted Infections in Cervicovaginal Exfoliative Samples in Mexican Women

“…was detected in coinfection with these pathogens, the main key questions are formulated. This yeast inhibits growths or the virulence of other pathogens, perhaps providing chemical resources for bacterial survival in the microenvironment, or promoting microorganism dissemination [32]. Our report has some limitations since we designed the panel test with no specific detection of Candida species.…”

Importance of Candida infection and fluconazole resistance in women with vaginal discharge syndrome in Namibia

“…A study by Kruppa and colleagues demonstrated a novel interaction between Chlamydia trachomatis and C. albicans via the binding of elementary bodies of Chlamydia trachomatis to C. albicans yeast and hyphal forms. This binding was shown to considerably decrease the capacity of Chlamydia trachomatis to infect human cervical epithelial cells, thereby decreasing its disease progression [ 44 ]. In contrast, another study illustrated that biofilms related to VVC may act as a reservoir for Chlamydia trachomatis [ 3 ].…”

A Yersinia ruckeri TIR Domain-Containing Protein (STIR-2) Mediates Immune Evasion by Targeting the MyD88 Adaptor

“…However, from the ratio of exposure/binding rate of these bacteria that cause disease and death are still a minority [33]. In many cases, the asymptomatic presence of bacteria is a prerequisite for disease [34,35,36,37,38]. Therefore, we believe that during the invisible carrying of bacteria in the host, genetic factors that promote bacterial adaptation (including viability and reproductive capacity) and the infection are worthy of attention.…”