Ming-Jie Xiang

Candida glabrata is an opportunistic pathogen with increasing clinical significance due to its innate antifungal resistance. This study reveals the critical role of the phospholipid flippase Drs2 (P4-ATPase) in maintaining fungal pathogenicity and stress adaptation. The DRS2 deletion mutant exhibited impaired growth, heightened drug susceptibility, and defective stress responses, including compromised oxidative stress tolerance and autophagy. Importantly, the mutant showed reduced survival in macrophages while eliciting stronger proinflammatory responses, along with attenuated virulence in a Galleria mellonella infection model. Further analysis demonstrated diminished biofilm formation and impaired metabolic flexibility under nutrient-limited conditions. Through transcriptomic profiling, we identified Drs2 as a key regulator of MAPK signaling pathways, cell wall integrity, and oxidative stress responses. These findings collectively establish Drs2 as a central coordinator of membrane homeostasis that critically links cellular stress adaptation to virulence in C. glabrata. These findings identify Drs2 as a promising target for antifungal intervention and provide new insight into the biological functions of lipid flippases in fungal pathogens.

Objectives: We aim to clarify the association and strength of association between antiphospholipid syndrome (APS) and adverse pregnancy outcomes. Methods: Our study included an analysis of 191 hospitalized singleton pregnant women with APS and 984 healthy singleton pregnant women at Obstetrics and Gynecology Hospital Affiliated to Fudan University from July 2017 to September 2023. The exposure factor was diagnosed as antiphospholipid syndrome, and the main outcomes were adverse pregnancy outcomes, including miscarriage, preterm birth, low birth weight, gestational hypertension, and eclampsia. Results: Our analysis indicated that the odds ratio (OR) for miscarriage in APS patients was 2.50 (95 % CI, 1.025 ± 15.794; p=0.046), for preterm birth was 2.8 (95 % CI, 1.025 ± 15.794; p=0.046), for low birth weight was 2.28 (95 % CI, 1.025 ± 15.794; p=0.046), and for fetal growth restriction was OR=2.48 (1.45, 4.23) p0.05. After adjustment for confounders of age and BMI confounders, the odds ratio (OR) for miscarriage was 2.50 (95 % CI: 1.52–4.11) p0.05. After adjustment for confounders of age, BMI, eclampsia and diabetes, the OR for preterm infants were 3.06 (95 % CI: 1.87–5.00) p<0.05, and those of low birth weight infants were 2.55 (95 % CI: 1.49–4.37) p<0.05. After adjustment for confounders of age, BMI, diabetes, eclampsia, and gestational week, the OR for low birth weight infants was 2.02 (95 % CI: 1.26–3.26) p<0.05. Conclusions: Antiphospholipid syndrome was significantly associated with the risk of miscarriage, preterm birth, low birth weight, and intrauterine growth restriction as adverse pregnancy outcomes.

This study evaluated the performance of the simultaneous amplification and testing (SAT) assay for detecting common Candida species in vaginal specimens compared with culture (gold standard) at the Obstetrics and Gynecology Hospital of Fudan University from December, 2024 to January, 2025. Speimens were analyzed by both Candida culture (with MALDI-TOF MS identification) and the SAT-Candida assay. Discordant results were further confirmed by real-time polymerase chain reaction (RT-PCR) and bidirectional sequencing. A comparative analysis (kappa coefficient) was conducted as well. We assessed the limit of detection, technical specificity, repeatability and the clinical diagnostic effectiveness, including sensitivity, specificity, diagnostic accuracy, positive predictive value (PPV), and negative predictive value (NPV) of SAT-Candida assay. In our study, among the 472 initially collected specimens, 5 were excluded because the presence of the Candida species were outside the detection spectrum of the SAT-Candida assay. The ages of the rest 467 cases ranged from 13 to 77 years old, and by comparison with SAT-Candida assay and Candida culture, 444 concordant results and 23 discordant results were discovered. After the reconfirmation, the SAT-Candida assay presented a overall sensitivity of 98.7%, specificity of 97.8%, PPV of 97.9%, NPV of 98.7%, and diagnostic accuracy of 98.3% in detecting Candida species. The kappa value between Candida culture and SAT-Candida assay in detecting Candida species was 0.91. This SAT-Candida assay is acute, highly sensitive, and specific, which can be applied as an optimal diagnostic tool for detecting and identifying common Candida species from vaginal samples of vulvovaginal candidiasis (VVC) suspected patients. The online version contains supplementary material available at 10.1186/s12941-025-00823-6.

Background: Invasive candidiasis (IC) is an increasingly common, expensive, and potentially fatal infection. However, IC caused by multiple Candida species is rarely reported in China. Herein, we revealed a complex IC caused by multiple Candida species, comprising the rare C. norvegensis, C. albicans, C. glabrata, and C. tropicalis. The resistance mechanism of azole and echinocandin resistance were explored further.Methods: The isolates were confirmed using internal transcribed spacer (ITS) sequencing. The resistance mechanisms were investigated using PCR-based sequencing, quantitative real-time reverse transcription PCR, and rhodamine 6G efflux quantification.Results: Antifungal susceptibility testing showed this complex infection was associated with cross-resistance to azole and echinocandin drugs. For C. glabrata, the acquired echinocandin resistance was likely caused by a novel mutational pattern (1,3-beta-D-glucan synthase subunits FKS1-S629P and FKS2-W1497stop) while the acquired azole resistance in C. glabrata RJ05 was related to complex mechanisms including enhanced efflux activity, pleiotropic drug resistance 1 (PDR1) mutation, and increased expression of Candida drug resistance 1 (CDR1) and CDR2. Additionally, the azole resistance of C. tropicalis was caused by two lanosterol 14-alpha demethylase (ERG11) mutations: Y132F and S154F.Conclusion: Our study revealed a case of clinically complex, multiple Candida invasive infections, further uncovering the resistance mechanisms to azoles and echinocandins. These findings provide valuable references for the diagnosis and treatment of invasive candidiasis (IC) in clinical practice.

Background: The increasing incidence and high mortality rate of Candida glabrata infection in ICU patients is an important issue. Therefore, it is imperative to investigate the antifungal susceptibility profiles and epidemiological characteristics in local regions.Methods: Herein, antifungal susceptibility testing was conducted to determine the minimum inhibitory concentrations (MICs) of eight antifungal drugs. Multilocus sequence typing (MLST) was used to study the strain genotype, geographical distribution, and susceptibility to antifungal agents among C. glabrata isolates. The mechanism of echinocandin resistance was explored by sequencing the FKS1 and FKS2 genes (encoding 1,3-β-D-glucan synthases) of echinocandin-resistant C. glabrata strains. Moreover, we further investigated the clinical manifestations and the various risk factors of patients infected with C. glabrata in the ICU.Results: We selected 234 C. glabrata isolates from 234 patients in the ICU randomly for the follow-up study. Cross-resistance was found among the ICU C. glabrata isolates. Analysis using MLST showed that the genetic diversity among the C. glabrata isolates was low. Furthermore, sequence type showed no correlation with the antifungal resistance profiles, but was associated with geographical distribution. We also revealed novel mutations in FKS1 (S629P) and FKS2 (W1497stop) that mediated high-level echinocandin resistance (MIC >8 µg/mL). More than 14 days’ stay in ICU (P=0.007), Acute Physiology and Chronic Health Evaluation II (APACHE-II) score (P=0.024), prior antifungal exposure (P=0.039) and lung disease (P=0.036) were significantly associated with antifungal resistant/non-wild-type C. glabrata infection.Conclusion: Our study shed light on the antifungal susceptibility, molecular epidemiology, and clinical risk factors of C. glabrata in the ICU of a Chinese Tertiary Hospital. Importantly, we revealed the molecular mechanism of echinocandin resistance. These results highlight the significance of continued surveillance in ICUs and provide data support for the treatment of C. glabrata in clinics.

Introduction: Candida glabrata has emerged as a fungal pathogen with high infection and mortality rates, and its primary virulence factors are related to adhesion and biofilm formation. These virulence factors in C.glabrata are primarily mediated by epithelial adhesins (Epas), most of which are encoded in subtelomeric regions and regulated by subtelomeric silencing mechanisms. The transcription factor Mss11, known for its regulatory role in adhesion, biofilm formation, and filamentous growth in Saccharomyces cerevisiae and Candida albicans, has also been implicated in the expression of EPA6, suggesting its potential influence on C.glabrata virulence. The present study aims to determine the regulatory role of Mss11 in the virulence of C. glabrata.Methods: In this work, a Δmss11 null mutant and its complemented strain were constructed from a C.glabrata standard strain. The impact of the transcription factor Mss11 on the virulence of C.glabrata was investigated through a series of phenotypic experiments, including the microbial adhesion to hydrocarbons (MATH) test, adherence assay, biofilm assay, scanning electron microscopy and Galleria mellonella virulence assay. Furthermore, transcriptome sequencing, quantitative reverse transcription polymerase chain reaction (RT-qPCR), and chromatin immunoprecipitation sequencing (ChIP-seq) were employed to investigate the molecular mechanisms behind the regulation of Mss11.Results: In C.glabrata, the loss of MSS11 led to a significant reduction in several virulence factors including cell surface hydrophobicity, epithelial cell adhesion, and biofilm formation. These observations were consistent with the decreased virulence of the Δmss11 mutant observed in the Galleria mellonella infection model. Further exploration demonstrated that Mss11 modulates C. glabrata virulence by regulating EPA1 and EPA6 expression. It binds to the upstream regions of EPA1 and EPA6, as well as the promoter regions of the subtelomeric silencing-related genes SIR4, RIF1, and RAP1, indicating the dual regulatory role of Mss11.Conclusion: Mss11 plays a crucial role in C. glabrata adhesion and biofilm formation, and thus has a broad influence on virulence. This regulation is achieved by regulating the expression of EPA1 and EPA6 through both promoter-specific regulation and subtelomeric silencing.

Background: As highly-conserved types of lipid flippases among fungi, P4-ATPases play a significant role in various cellular processes. Cdc50 acts as the regulatory subunit of flippases, forming heterodimers with Drs2 to translocate aminophospholipids. Cdc50 homologs have been reported to be implicated in protein trafficking, drug susceptibility, and virulence in Saccharomyces cerevisiae, Candida albicans and Cryptococcus neoformans. It is likely that Cdc50 has an extensive influence on fungal cellular processes. The present study aimed to determine the function of Cdc50 in Candida glabrata by constructing a Δcdc50 null mutant and its complemented strain. Results: In Candida glabrata, the loss of Cdc50 led to difficulty in yeast budding, probably caused by actin depolarization. The Δcdc50 mutant also showed hypersensitivity to azoles, caspofungin, and cell wall stressors. Further experiments indicated hyperactivation of the cell wall integrity pathway in the Δcdc50 mutant, which elevated the major cell wall contents. An increase in exposure of β-(1,3)-glucan and chitin on the cell surface was also observed through flow cytometry. Interestingly, we observed a decrease in the phagocytosis rate when the Δcdc50 mutant was co-incubated with THP-1 macrophages. The Δcdc50 mutant also exhibited weakened virulence in nematode survival tests. Conclusion: The results suggested that the lipid flippase subunit Cdc50 is implicated in yeast budding and cell wall integrity in C. glabrata, and thus have a broad influence on drug susceptibility and virulence. This work highlights the importance of lipid flippase, and offers potential targets for new drug research.

Background The Candida glabrata does not develop into a pathogenic hiphal form; however, it has become the second most common pathogen of fungal infections in humans, partly because of its adhesion ability and virulence. Objectives The present study aimed to determine whether Flo8, a transcription factor that plays an important role in the virulence and drug resistance in Candida albicans, has a similar role in C. glabrata. Methods We constructed FLO8 null strains of a C. glabrata standard strain and eight clinical strains from different sources, and a FLO8 complemented strain. Real-time quantitative PCR, biofilm formation assays, hydrophobicity tests, adhesion tests, Caenorhabditis elegans survival assay, and drug-susceptibility were then performed. Results Compared with the wild-type strains, the biofilm formation, hydrophobicity, adhesion, and virulence of the FLO8-deficient strains decreased, accompanied by decreased expression of EPA1, EPA6, and EPA7. On the other hand, it showed no changes in antifungal drug resistance, although the expression levels of CDR1, CDR2, and SNQ2 increased after FLO8 deletion. Conclusions These results indicated that Flo8 is involved in the adhesion and virulence of C. glabrata, with FLO8 deletion leading to decreased expression of EPA1, EPA6, and EPA7 and decreased biofilm formation, hydrophobicity, adhesion, and virulence.