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Few therapeutic drugs and increased drug resistance have aggravated the current treatment difficulties of Cryptococcus in recent years. To better understand the antifungal drug resistance mechanism and treatment strategy of cryptococcosis. In this review, by combining the fundamental features of Cryptococcus reproduction leading to changes in its genome, we review recent research into the mechanism of four current anti-cryptococcal agents, coupled with new therapeutic strategies and the application of advanced technologies WGS and CRISPR-Cas9 in this field, hoping to provide a broad idea for the future clinical therapy of cryptococcosis.

Generally, Cryptococcus initially infects the respiratory tract, but can spread, eventually crossing the blood-brain barrier (BBB) and causing meningitis or meningoencephalitis. Specifically, Cryptococcus invades the vascular endothelial cells of the BBB, from which it enters the brain. The main mechanisms through which Cryptococcus crosses the BBB are transcellular traversal, the paracellular pathway, and via Trojan horse. In this paper, the mechanisms by which Cryptococcus crosses the BBB were explained in detail. In addition to pathways of entry to the brain, this paper presents a discussion on some rare cryptococcal infections and provides some insights for future research directions. [ABSTRACT FROM AUTHOR]

Cryptococcus is a family of strongly infectious pathogens that results in a wide variety of symptoms, particularly threatening the patients undergoing the immune‐deficiency or medical treatment. Rapidly identifying Cryptococcus subtypes and accurately quantifying their contents remain urgent needs for infection control and timely therapy. However, traditional detection techniques heavily rely on expensive, specialized instruments, significantly compromising their applicability for large‐scale population screening. In this work, we report a portable microwell array chip platform integrated with a deep learning‐based image recognition program, which enables rapid, precise quantification of the specific subtypes of Cryptococcus. The platform features four zones of microwell arrays preloaded with the subtype‐targeted CRISPR–Cas12a system that avoid dependence on slow, instrumental‐mediated target amplification, achieving rapid (10 min), high specificity for identifying the sequence of Cryptococcus. The deep learning‐based image recognition program utilizing segment anything model (SAM) significantly enhances automation and accuracy in identifying target concentrations, which eventually achieves ultra‐low limit of detection (0.5 pM) by personal smartphones. This platform can be further customized to adapt to various scenarios in clinical settings. [ABSTRACT FROM AUTHOR]

Cryptococcus gattii (C. gattii) is a fungal pathogen that once caused an outbreak of cryptococcosis on Vancouver Island, and had spread worldwide, while few data were available in China. In this study, seven clinical isolates of C. gattii VGII were collected from 19 hospitals, Multi-locus Sequence Typing (MLST) analysis and whole-genome sequencing (WGS) was performed, combined with published data for phylogenetic analysis. In addition, in vitro antifungal susceptibility testing, phenotypic analysis, and in vivo virulence studies were performed, subsequently, histopathological analysis of lung tissue was performed. C.gattii VGII infected patients were mainly immunocompetent male, and most of them had symptoms of central nervous system (CNS) involvement. MLST results showed that isolates from China exhibited high genetic diversity, and sequence type (ST) 7 was the major ST among the isolates. Some clinical isolates showed a close phylogenetic relationship with strains from Australia and South America. All clinical isolates did not show resistance to antifungal drugs. In addition, there was no correlation between virulence factors (temperature, melanin production, and capsule size) and virulence while in vivo experiments showed significant differences in virulence among strains. Lung fungal burden and damage to lung tissue correlated with virulence, and degree of damage to lung tissue in mice may highlight differences in virulence. Our work seeks to provide useful data for molecular epidemiology, antifungal susceptibility, and virulence differences of C. gattii VGII in China. Author summary: Cryptococcus gattii is one of the life-threatening fungal pathogens that can infect immunocompetent individuals. C.gattii can be invaded through the respiratory tract and can be spread to the brain, causing meningoencephalitis and even death. In 1999, an outbreak of C. gattii VGII occurred on Vancouver Island in Canada and spread in the Pacific Northwest region, which attracted more attention. Compared with other nations, the data of C.gattii VGII in China was limited. To better understand the molecular epidemiology and microbiological characteristics of C.gattii VGII isolates from China, bioinformatics analysis and in vivo and in vitro experiments were performed for clinical strains. Multi-locus Sequence Typing and whole-genome sequencing reveal the genetic diversity of the isolates and genetic relationships with isolates from other countries. The antifungal drug susceptibility and virulence differences of the isolates were also investigated. The authors expect that our work can provide useful data for the prevention and control of C. gattii VGII in China and to draw more attention to C. gattii. [ABSTRACT FROM AUTHOR]

Linqi Wang should be listed as the ninth author and affiliated with State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China. Correction: Molecular epidemiology and microbiological characteristics of Cryptococcus gattii VGII isolates from China Linqi Wang is not included in the author byline. [Extracted from the article]

Fast and accurate detection of Cryptococcus and precise differentiation of its subtypes is of great significance in protecting people from cryptococcal disease and preventing its spread in populations. However, traditional Cryptococcus identification and detection techniques still face significant challenges in achieving high analysis speed as well as high sensitivity. In this work, we report an electric microfluidic biochip. Compared to conventional methods that take several hours or even a day, this chip can detect Cryptococcus within 20 min, and achieve its maximum detection limit within 1 h, with the ability to differentiate between the Cryptococcus neoformans (NEO) and rare Cryptococcus gattii (GAT) efficiently, which accounts for nearly 100%. This device integrated two functional zones of an electroporation lysis (EL) zone for rapid cell lysis (<30 s) and an electrochemical detection (ED) zone for sensitive analysis of the released nucleic acids. The EL zone adopted a design of microelectrode arrays, which obtains a large electric field intensity at the constriction of the microchannel, addressing the safety concerns associated with high-voltage lysis. The device enables a limit of detection (LOD) of 60 pg/mL for NEO and 100 pg/mL for GAT through the modification of nanocomposites and specific probes. In terms of the detection time and sensitivity, the integrated microfluidic biochip demonstrates broad potential in Cryptococcus diagnosis and disease prevention. [ABSTRACT FROM AUTHOR]