Biofilm Formation by Cryptococcus neoformans

Abstract

The fungus Cryptococcus neoformans possesses a polysaccharide capsule and can form biofilms on medical devices. The increasing use of ventriculoperitoneal shunts to manage intracranial hypertension associated with cryptococcal meningoencephalitis highlights the importance of investigating the biofilm-forming properties of this organism. Like other microbe-forming biofilms, C. neoformans biofilms are resistant to antimicrobial agents and host defense mechanisms, causing significant morbidity and mortality. This chapter discusses the recent advances in the understanding of cryptococcal biofilms, including the role of its polysaccharide capsule in adherence, gene expression, and quorum sensing in biofilm formation. We describe novel strategies for the prevention or eradication of cryptococcal colonization of medical prosthetic devices. Finally, we provide fresh thoughts on the diverse but interesting directions of research in this field that may result in new insights into C. neoformans biology.

Activity of Scorpion Venom-Derived Antifungal Peptides against Planktonic Cells of Candida spp. and Cryptococcus neoformans and Candida albicans Biofilms

“…The estimated yearly incidence of cryptococcal meningitis is almost one million cases, causing 625,000 deaths (Park et al, 2009). In addition, Candida species and C. neoformans can form biofilms on abiotic and biotic surfaces (Mayer et al, 2013; Martinez and Casadevall, 2015). Of particular interest is the formation of biofilms by C. albicans , which confers specialized properties to the microorganism that complicate treatment, such as the increased resistance to antimicrobial drugs and the ability to evade the host immune system, among others (Finkel and Mitchell, 2011; Fanning and Mitchell, 2012).…”

The Extracellular Matrix of Fungal Biofilms

“…For measurement of known matrix entities, monoclonal antibodies have been produced for both imaging purposes and quantification in microtiter based assays such as ELISA (Zarnowski et al 2014;Martinez and Casadevall 2015). For further characterization of the matrix material, both SEM and TEM have been used, as well as atomic force microscopy (AFM) (Yang et al 2011;Lal et al 2010).…”

“…Cryptococcus neoformans, which can cause meningoencephalitis in humans, has the ability to form biofilms on polystyrene plates and on the surfaces of medical devices such as the shunts used to treat intracranial hypertension (Martinez and Casadevall 2015). During biofilm formation, extracellular matrix increases over time and provides structure and complexity to groups of adherent cells Martinez and Casadevall 2007).…”

Nanotechnology-based drug delivery systems for control of microbial biofilms: a review

“…66 The yeast species Candida albicans is known to frequently form biofilms and has been extensively studied by medical researchers, as it is the third most common cause 72,73 Further, some other types of fungi, such as Malassezia spp., 74 Pneumocystis spp., 75 Histoplasma capsulatum, 76 Cryptococcus neoformans, 77 and Cryptococcus gatti, 78 may also be associated with the infections in humans.…”

“…The fungus possesses a polysaccharide capsule that completely surrounds it for the protection against phagocytosis by the cells of the immune system and has a direct relationship with the formation of biofilms. 77 Fungal infections that are caused by Trichosporon spp. are also considered as a serious threat to humans as their diagnosis and therapy are also complex.…”