Treatment strategies for cryptococcal infection: challenges, advances and future outlook

In the paper

“hypermutator isolates derived from both the clinic and the laboratory lead to the rapid emergence of resistance to drugs such as rapamycin, FK506 (ref.33), flucytosine32, fluconazole and even amphotericin B30.”

What the sources say

• Supported

  The Results section reports rapid emergence of fluconazole- and amphotericin B-resistant colonies in laboratory mismatch-repair mutants, and increased spontaneous fluconazole resistance in the clinical isolate C23. In the citing sentence, this paper is cited for fluconazole and amphotericin B; rapamycin, FK506, and flucytosine have other citations. The paper does not show amphotericin B resistance in the clinical isolates. (LLM, conf=0.89)

  cites [30] Boyce, K. J. et al. Mismatch repair of DNA replication errors contributes to microevolution in the pathogenic fungus Cryptococcus neoformans. mBio 8, e00595-17 (2017). This report is one of the first of a hypermutator strain in clinical isolates, which has a fitness advantage owing to mutations in mismatch repair genes. source
• Supported

  The Results section (“Hypermutation mediates resistance to 5FC”) reports that engineered msh2 deletion mutants and naturally occurring hypermutator strains acquired flucytosine (5FC) resistance at elevated rates. The citation to this paper is attached to flucytosine; the other drugs have separate citations in the citing sentence. (LLM, conf=0.92)

  cites [32] Billmyre, R. B., Applen Clancey, S., Li, L. X., Doering, T. L. & Heitman, J. 5-Fluorocytosine resistance is associated with hypermutation and alterations in capsule biosynthesis in Cryptococcus. Nat. Commun. 11, 127 (2020). source
• Supported

  The citation is attached to FK506, not to the later drugs, which have separate citations. In Results, the paper reports that a hypermutator rapidly acquired resistance under FK506/rapamycin exposure at 37°C; it also reports elevated resistance rates in a naturally occurring hypermutator and laboratory-created msh2 mutants. The copy provides no page numbers for these passages. (LLM, conf=0.93)

  cites [33] Billmyre, R. B., Clancey, S. A. & Heitman, J. Natural mismatch repair mutations mediate phenotypic diversity and drug resistance in Cryptococcus deuterogattii. eLife 6, e28802 (2017). source

In the paper

“a subset of Cryptococcus isolates have been identified as hypermutator strains30,31, which contain mutations in core genes in the DNA mismatch repair pathway, most notably MSH2 (refs30,32,33)”

What the sources say

• Not checked yetcites [30] Boyce, K. J. et al. Mismatch repair of DNA replication errors contributes to microevolution in the pathogenic fungus Cryptococcus neoformans. mBio 8, e00595-17 (2017). This report is one of the first of a hypermutator strain in clinical isolates, which has a fitness advantage owing to mutations in mismatch repair genes. source
• Not checked yetcites [31] Boyce, K. J., Cao, C., Xue, C. & Idnurm, A. A spontaneous mutation in DNA polymerase POL3 during in vitro passaging causes a hypermutator phenotype in Cryptococcus species. DNA Repair 86, 102751 (2020). source
• Not checked yetcites [32] Billmyre, R. B., Applen Clancey, S., Li, L. X., Doering, T. L. & Heitman, J. 5-Fluorocytosine resistance is associated with hypermutation and alterations in capsule biosynthesis in Cryptococcus. Nat. Commun. 11, 127 (2020). source

In the paper

“a mutation in the proofreading domain of POL3 (encoding the catalytic subunit of DNA polymerase δ) was also shown to confer the hypermutator phenotype31.”

What the sources say

• Not checked yetcites [31] Boyce, K. J., Cao, C., Xue, C. & Idnurm, A. A spontaneous mutation in DNA polymerase POL3 during in vitro passaging causes a hypermutator phenotype in Cryptococcus species. DNA Repair 86, 102751 (2020). source

In the paper

“Laboratory studies have shown that selection for resistance to environmental agrochemicals, primarily through the upregulation of the azole target gene ERG11 and drug efflux pumps, can lead to cross-resistance to clinically deployed antifungals19,20.”

What the sources say

• Not checked yetcites [19] Bastos, R. W. et al. From the environment to the host: how non-azole agrochemical exposure affects the antifungal susceptibility and virulence of Cryptococcus gattii. Sci. Total Environ. 681, 516–523 (2019). source
• Not checked yetcites [20] Bastos, R. W. et al. Environmental triazole induces cross-resistance to clinical drugs and affects morphophysiology and virulence of Cryptococcus gattii and C. neoformans. Antimicrob. Agents Chemother. 62, e01179-17 (2018). source

In the paper

“most commonly involving disomy of chromosome 1, which contains ERG11 and the predominant efflux pump gene AFR1 (ref.17).”

What the sources say

• Not checked yetcites [17] Sionov, E., Lee, H., Chang, Y. C. & Kwon-Chung, K. J. Cryptococcus neoformans overcomes stress of azole drugs by formation of disomy in specific multiple chromosomes. PLoS Pathog. 6, e1000848 (2010). source

In the paper

“This phenomenon was first described in 1999, when researchers observed that a subset of Cryptococcus cells were able to grow at azole concentrations well above the inhibitory concentration in vitro21.”

What the sources say

• Not checked yetcites [21] Mondon, P. et al. Heteroresistance to fluconazole and voriconazole in Cryptococcus neoformans. Antimicrob. Agents Chemother. 43, 1856–1861 (1999). source

In the paper

“However, hypermutator phenotypes can also result from mutations in other genes, such as MSL1 and PMS1 (ref.30).”

What the sources say

• Not checked yetcites [30] Boyce, K. J. et al. Mismatch repair of DNA replication errors contributes to microevolution in the pathogenic fungus Cryptococcus neoformans. mBio 8, e00595-17 (2017). This report is one of the first of a hypermutator strain in clinical isolates, which has a fitness advantage owing to mutations in mismatch repair genes. source

In the paper

“Disomy of chromosome 4 is the second most common aneuploidy conferring azole heteroresistance, which is largely attributed to three genes: SEY1, which encodes a GTPase, and GLO3 and GCS2, which encode ADP-ribosylation factor proteins25.”

What the sources say

• Not checked yetcites [25] Ngamskulrungroj, P. et al. Characterization of the chromosome 4 genes that affect fluconazole-induced disomy formation in Cryptococcus neoformans. PLoS ONE 7, e33022 (2012).

In the paper

“Heteroresistance primarily occurs through the formation of aneuploid cells, both in vitro and in vivo17,22,24 (Fig. 1)”

What the sources say

• Not checked yetcites [17] Sionov, E., Lee, H., Chang, Y. C. & Kwon-Chung, K. J. Cryptococcus neoformans overcomes stress of azole drugs by formation of disomy in specific multiple chromosomes. PLoS Pathog. 6, e1000848 (2010). source
• Not checked yetcites [22] Stone, N. R. et al. Dynamic ploidy changes drive fluconazole resistance in human cryptococcal meningitis. J. Clin. Invest. 129, 999–1014 (2019). This paper presents the first clinical samples to demonstrate fluconazole heteroresistance due to aneuploidy, achieved through increased efflux levels. source
• Not checked yetcites [24] Sionov, E., Chang, Y. C. & Kwon-Chung, K. J. Azole heteroresistance in Cryptococcus neoformans: emergence of resistant clones with chromosomal disomy in the mouse brain during fluconazole treatment. Antimicrob. Agents Chemother. 57, 5127–5130 (2013). source

In the paper

“a phase II trial demonstrated that a single high dose of LAmB is of equivalent efficacy to a 7-day course of DAmB10”

What the sources say

• Not checked yetcites [10] Jarvis, J. N. et al. Short-course high-dose liposomal amphotericin B for human immunodeficiency virus-associated cryptococcal meningitis: a phase 2 randomized controlled trial. Clin. Infect. Dis. 68, 393–401 (2019). source

In the paper

“Furthermore, these transposable elements also mediated resistance to rapamycin, FK506 and flucytosine38.”

What the sources say

• Not checked yetcites [38] Gusa, A. et al. Transposon mobilization in the human fungal pathogen Cryptococcus is mutagenic during infection and promotes drug resistance in vitro. Proc. Natl Acad. Sci. USA 117, 9973–9980 (2020). This paper is the first description of transposon-mediated antifungal resistance in Cryptococcus spp. source

In the paper

“Resistance was mediated by inactivation of the genes encoding the targets of 5-fluoroorotic acid, Ura3 and Ura5, by the movement of the DNA transposon T1 and the retrotransposon TCN12 within the fungal genome38.”

What the sources say

• Not checked yetcites [38] Gusa, A. et al. Transposon mobilization in the human fungal pathogen Cryptococcus is mutagenic during infection and promotes drug resistance in vitro. Proc. Natl Acad. Sci. USA 117, 9973–9980 (2020). This paper is the first description of transposon-mediated antifungal resistance in Cryptococcus spp. source

In the paper

“An important contribution of the titan cell to drug resistance is that this attribute is retained in its progeny26.”

What the sources say

• Not checked yetcites [26] Gerstein, A. C. et al. Polyploid titan cells produce haploid and aneuploid progeny to promote stress adaptation. mBio 6, e01340-15 (2015). source

In the paper

“hypermutator strains have a 15% higher rate of resistance to this prodrug (the active drug is fluorouracil) when compared with isolates that do not possess a hypermutator mutation.”

What the sources say

• Not checked yetcites [32] Billmyre, R. B., Applen Clancey, S., Li, L. X., Doering, T. L. & Heitman, J. 5-Fluorocytosine resistance is associated with hypermutation and alterations in capsule biosynthesis in Cryptococcus. Nat. Commun. 11, 127 (2020). source

In the paper

“caspofungin treatment of a cdc50Δ mutant resulted in heightened intracellular calcium and hyperactivation of calcineurin-dependent stress responses47.”

What the sources say

• Not checked yetcites [47] Cao, C., Wang, Y., Husain, S., Soteropoulos, P. & Xue, C. A mechanosensitive channel governs lipid flippase-mediated echinocandin resistance in Cryptococcus neoformans. mBio 10, e01952-19 (2019).

In the paper

“under fluconazole-induced stress conditions they are more often aneuploid, specifically with a disomy of chromosomes 1 or 4, which results in improved growth in the presence of fluconazole26.”

What the sources say

• Not checked yetcites [26] Gerstein, A. C. et al. Polyploid titan cells produce haploid and aneuploid progeny to promote stress adaptation. mBio 6, e01340-15 (2015). source

In the paper

“a 2020 report linked transposons to drug resistance in C. neoformans38.”

What the sources say

• Not checked yetcites [38] Gusa, A. et al. Transposon mobilization in the human fungal pathogen Cryptococcus is mutagenic during infection and promotes drug resistance in vitro. Proc. Natl Acad. Sci. USA 117, 9973–9980 (2020). This paper is the first description of transposon-mediated antifungal resistance in Cryptococcus spp. source

In the paper

“A forward genetic screen to identify suppressor mutations that restore caspofungin resistance in a cdc50Δ background revealed that inactivation of the calcium channel protein Crm1 reduced intracellular calcium, normalized calcineurin signalling and reinstated caspofungin resistance47.”

What the sources say

• Not checked yetcites [47] Cao, C., Wang, Y., Husain, S., Soteropoulos, P. & Xue, C. A mechanosensitive channel governs lipid flippase-mediated echinocandin resistance in Cryptococcus neoformans. mBio 10, e01952-19 (2019).

In the paper

“the thicker cell walls of older C. neoformans cells have been implicated in their increased antifungal resistance42.”

What the sources say

• Not checked yetcites [42] Bouklas, T. et al. Old Cryptococcus neoformans cells contribute to virulence in chronic cryptococcosis. mBio 4, e00455-13 (2013). source

In the paper

“During cryptococcal infection of mouse lungs, ~20% of fungal cells transform from haploid yeast into polyploid titan cells29,147, making up a substantial subset of the population.”

What the sources say

• Not checked yetcites [29] Okagaki, L. H. et al. Cryptococcal cell morphology affects host cell interactions and pathogenicity. PLoS Pathog. 6, e1000953 (2010). source
• Not checked yetcites [147] Zaragoza, O. et al. Fungal cell gigantism during mammalian infection. PLoS Pathog. 6, e1000945 (2010). source

In the paper

“This enhanced resistance was caused by loss-of-function mutations in the genes encoding the purine-cytosine permease Fcy2 and the uracil phosphoribosyltransferase Fur1, which import and process the prodrug, respectively, as well as a mutation in the gene encoding Uxs1, which produces UDP-xylose, a precursor in capsule biosynthesis32.”

What the sources say

• Not checked yetcites [32] Billmyre, R. B., Applen Clancey, S., Li, L. X., Doering, T. L. & Heitman, J. 5-Fluorocytosine resistance is associated with hypermutation and alterations in capsule biosynthesis in Cryptococcus. Nat. Commun. 11, 127 (2020). source

In the paper

“titan cell populations also have an increased growth advantage compared with typical haploid cells on exposure to oxidative and nitrosative stress, which is not mediated through aneuploid formation26”

What the sources say

• Not checked yetcites [26] Gerstein, A. C. et al. Polyploid titan cells produce haploid and aneuploid progeny to promote stress adaptation. mBio 6, e01340-15 (2015). source

In the paper

“the only new class of antifungal drugs developed in decades, the echinocandins, displays negligible antifungal activity against Cryptococcus spp.”

• Also stated in: § Treatments for cryptococcal infections · plain

  “Cryptococcus spp. are intrinsically resistant to echinocandins”

What the sources say

• Not checked yetcites [2] Lee, Y., Puumala, E., Robbins, N. & Cowen, L. E. Antifungal drug resistance: molecular mechanisms in Candida albicans and beyond. Chem. Rev. https://doi.org/10.1021/acs.chemrev.0c00199 (2020). source
• Not checked yetcites [8] Denning, D. W. Echinocandin antifungal drugs. Lancet 362, 1142–1151 (2003). source

In the paper

“the efficacy of the remaining therapeutics is hampered by host toxicity and pathogen resistance”

In the paper

“The majority of deaths are reported from resource-limited countries owing to a lack of access to drugs and the high cost of effective treatments, signifying the urgency in developing affordable therapeutics against these deadly fungal pathogens7.”

What the sources say

• Not checked yetcites [7] Loyse, A. et al. Leave no one behind: response to new evidence and guidelines for the management of cryptococcal meningitis in low-income and middle-income countries. Lancet Infect. Dis. 19, e143–e147 (2019). source

In the paper

“Cryptococcus spp. display extraordinary genomic plasticity and physiological adaptability, which allows resilience to antifungal assault (Fig. 1).”

In the paper

“current antifungal drug treatments for invasive fungal infections are limited to polyenes, azoles and echinocandins2”

What the sources say

• Not checked yetcites [2] Lee, Y., Puumala, E., Robbins, N. & Cowen, L. E. Antifungal drug resistance: molecular mechanisms in Candida albicans and beyond. Chem. Rev. https://doi.org/10.1021/acs.chemrev.0c00199 (2020). source

In the paper

“Unfortunately, widespread antifungal use has fuelled the rapid emergence of drug resistance to all three classes of antifungal agents3.”

What the sources say

• Not checked yetcites [3] Fisher, M. C., Hawkins, N. J., Sanglard, D. & Gurr, S. J. Worldwide emergence of resistance to antifungal drugs challenges human health and food security. Science 360, 739–742 (2018). This important review highlights the impact that drug-resistant fungal species have on human health. source

In the paper

“Liposome bilayer-coated amphotericin B (LAmB) has been developed to reduce toxicity while retaining antifungal activity, mitigating the dosage limitation of conventional amphotericin B deoxycholate (DAmB)9.”

What the sources say

• Not checked yetcites [9] Stone, N. R., Bicanic, T., Salim, R. & Hope, W. Liposomal amphotericin B (AmBisome®): a review of the pharmacokinetics, pharmacodynamics, clinical experience and future directions. Drugs 76, 485–500 (2016). source

In the paper

“research suggests that either mis-segregation of chromosomes or compromised nuclear division leads to the formation of aneuploid cells under azole stress27–29.”

What the sources say

• Not checked yetcites [27] Altamirano, S. et al. Fluconazole-induced ploidy change in Cryptococcus neoformans results from the uncoupling of cell growth and nuclear division. mSphere 2, e00205–e00217 (2017). source
• Not checked yetcites [28] Chang, Y. C., Khanal Lamichhane, A. & Kwon-Chung, K. J. Cryptococcus neoformans, unlike Candida albicans, forms aneuploid clones directly from uninucleated cells under fluconazole stress. mBio 9, e01290-18 (2018).
• Not checked yetcites [29] Okagaki, L. H. et al. Cryptococcal cell morphology affects host cell interactions and pathogenicity. PLoS Pathog. 6, e1000953 (2010). source

In the paper

“Changes in the Cryptococcus capsule and cell wall contribute to resistance and virulence.”

In the paper

“Therefore, it was postulated that echinocandin resistance in Cryptococcus is mediated by calcineurin signalling (via Crm1), which is overstimulated as a result of CDC50 deletion, thereby triggering cell death47.”

What the sources say

• Not checked yetcites [47] Cao, C., Wang, Y., Husain, S., Soteropoulos, P. & Xue, C. A mechanosensitive channel governs lipid flippase-mediated echinocandin resistance in Cryptococcus neoformans. mBio 10, e01952-19 (2019).

In the paper

“The titan cell also plays a key part in stress adaptation and resistance to antifungal drugs26,150.”

What the sources say

• Not checked yetcites [26] Gerstein, A. C. et al. Polyploid titan cells produce haploid and aneuploid progeny to promote stress adaptation. mBio 6, e01340-15 (2015). source
• Not checked yetcites [150] Okagaki, L. H. et al. Cryptococcal titan cell formation is regulated by G-protein signaling in response to multiple stimuli. Eukaryot. Cell 10, 1306–1316 (2011). source

In the paper

“The inherent resistance of Cryptococcus spp. to echinocandins is a key limitation in the treatment of cryptococcosis8.”

What the sources say

• Not checked yetcites [8] Denning, D. W. Echinocandin antifungal drugs. Lancet 362, 1142–1151 (2003). source

In the paper

“the formation of Cryptococcus titan cells, which exhibit numerous alterations that likely contribute to drug resistance43 (Box 2).”

What the sources say

• Not checked yetcites [43] Zafar, H., Altamirano, S., Ballou, E. R. & Nielsen, K. A titanic drug resistance threat in Cryptococcus neoformans. Curr. Opin. Microbiol. 52, 158–164 (2019). This seminal review summarizes the current understanding of the mechanisms underlying antifungal resistance of the Cryptococcus titan cell. source

In the paper

“This resistance is paradoxical, as β-1,3-glucan synthase, the enzymatic target of the echinocandins, is essential in Cryptococcus and has been demonstrated to be potently inhibited by echinocandins biochemically44,45.”

What the sources say

• Not checked yetcites [44] Thompson, J. R. et al. A glucan synthase FKS1 homolog in Cryptococcus neoformans is single copy and encodes an essential function. J. Bacteriol. 181, 444–453 (1999). source
• Not checked yetcites [45] Maligie, M. A. & Selitrennikoff, C. P. Cryptococcus neoformans resistance to echinocandins: (1,3)β-glucan synthase activity is sensitive to echinocandins. Antimicrob. Agents Chemother. 49, 2851–2856 (2005). source

In the paper

“These data highlight a pivotal role of stress responses in mediating echinocandin resistance, which is exemplified by the identification of 14 caspofungin-sensitive C. neoformans mutants that are defective in the activation of stress responses, including calcineurin-dependent responses48.”

What the sources say

• Not checked yetcites [48] Pianalto, K. M., Billmyre, R. B., Telzrow, C. L. & Alspaugh, J. A. Roles for stress response and cell wall biosynthesis pathways in caspofungin tolerance in Cryptococcus neoformans. Genetics 213, 213–227 (2019). source

In the paper

“Fortunately, the crystal structure of the two subunits of calcineurin in a complex with the inhibitor FK506 and the FK506-binding protein FKBP12 from four prominent fungal pathogens, including C. neoformans, has been solved.”

What the sources say

• Not checked yetcites [77] Juvvadi, P. R. et al. Harnessing calcineurin–FK506–FKBP12 crystal structures from invasive fungal pathogens to develop antifungal agents. Nat. Commun. 10, 4275 (2019). This paper presents an excellent example of successful structure-guided drug design to develop fungal-specific calcineurin inhibitors. source

In the paper

“Therefore, the machinery responsible for capsule biosynthesis and structure, such as the xylosyltransferase Cxt1 (ref.57) and the lactonohydrolase Lhc1 (ref.41), represent ideal anti-virulence targets.”

What the sources say

• Not checked yetcites ref.57
• Not checked yetcites ref.41

In the paper

“Thus, many researchers have investigated the function of cell wall-related genes, finding that deletion of these genes has pleiotropic effects, including reduced virulence.”

In the paper

“Other fungal-selective calcineurin inhibitors have been obtained by screening FK506 analogues to identify compounds that synergize with fluconazole to clear fungal infections in mice78.”

What the sources say

• Not checked yetcites [78] Lee, Y. et al. In vitro and in vivo asssessment of FK506 analogs as novel antifungal drug candidates. Antimicrob. Agents Chemother. 62, e01627-18 (2018).

In the paper

“Furthermore, Lhc1 modulates immune responses, blocking phagocytosis of C. neoformans by macrophage-like cell lines in vitro41.”

What the sources say

• Not checked yetcites [41] Park, Y. D. et al. A role for LHC1 in higher order structure and complement binding of the Cryptococcus neoformans capsule. PLoS Pathog. 10, e1004037 (2014).

In the paper

“For example, the protein phosphatase calcineurin is essential for diverse drug-resistance and virulence phenotypes in pathogenic fungi76.”

What the sources say

• Not checked yetcites [76] Juvvadi, P. R., Lamoth, F. & Steinbach, W. J. Calcineurin as a multifunctional regulator: unraveling novel functions in fungal stress responses, hyphal growth, drug resistance, and pathogenesis. Fungal Biol. Rev. 28, 56–69 (2014). source

In the paper

“A genome-wide association study of C. neoformans isolates found sequence differences between clinical and environmental isolates in genes involved in virulence and stress responses, including CCK2 (encoding a casein kinase)74.”

What the sources say

• Not checked yetcites [74] Desjardins, C. A. et al. Population genomics and the evolution of virulence in the fungal pathogen Cryptococcus neoformans. Genome Res. 27, 1207–1219 (2017). source

In the paper

“These structures identified a specific residue that is conserved in the fungal FKBP12 but not the human FKBP12 and is crucial for FK506-mediated inhibition of calcineurin77”

What the sources say

• Not checked yetcites [77] Juvvadi, P. R. et al. Harnessing calcineurin–FK506–FKBP12 crystal structures from invasive fungal pathogens to develop antifungal agents. Nat. Commun. 10, 4275 (2019). This paper presents an excellent example of successful structure-guided drug design to develop fungal-specific calcineurin inhibitors. source

In the paper

“Additionally, comparative analysis of a series of isolates collected over the course of an infection revealed that later-stage isolates possessed enhanced thermotolerance, capsule production and stress adaptation compared with earlier-stage isolates75.”

What the sources say

• Not checked yetcites [75] Chen, Y. et al. Microevolution of serial clinical isolates of Cryptococcus neoformans var. grubii and C. gattii. mBio 8, e00166-17 (2017).

In the paper

“thus demonstrating the therapeutic potential of using small molecules to impair Cryptococcus spp. capsule formation.”

In the paper

“Finally, the macrolides clarithromycin and azithromycin, as well as thiazole derivatives, disrupt the integrity and reduce the thickness of the capsule, resulting in enhanced phagocytosis of Cryptococcus by murine macrophages59,60”

What the sources say

• Not checked yetcites [59] Nakamura, S. et al. Macrolides inhibit capsule formation of highly virulent Cryptococcus gattii and promote innate immune susceptibility. Antimicrob. Agents Chemother. 63, e02364-18 (2019).
• Not checked yetcites [60] de Sa, N. P. et al. Thiazole derivatives act on virulence factors of Cryptococcus spp. Med. Mycol. 57, 84–91 (2019). source

In the paper

“However, as current calcineurin inhibitors such as FK506 are immunosuppressive (through inhibition of host calcineurin), fungal-selective calcineurin inhibitors are needed76.”

What the sources say

• Not checked yetcites [76] Juvvadi, P. R., Lamoth, F. & Steinbach, W. J. Calcineurin as a multifunctional regulator: unraveling novel functions in fungal stress responses, hyphal growth, drug resistance, and pathogenesis. Fungal Biol. Rev. 28, 56–69 (2014). source

In the paper

“PLB1 mutants display attenuated virulence in mice owing to impaired titan cell formation, proliferation and survival within macrophages71.”

What the sources say

• Not checked yetcites [71] Evans, R. J. et al. Cryptococcal phospholipase B1 is required for intracellular proliferation and control of titan cell morphology during macrophage infection. Infect. Immun. 83, 1296–1304 (2015). source

In the paper

“and laccase-deficient mutants display attenuated pulmonary dissemination in vivo67.”

What the sources say

• Not checked yetcites [67] Noverr, M. C., Williamson, P. R., Fajardo, R. S. & Huffnagle, G. B. CNLAC1 is required for extrapulmonary dissemination of Cryptococcus neoformans but not pulmonary persistence. Infect. Immun. 72, 1693–1699 (2004). source

In the paper

“Additional studies have explored the potential of inhibiting TOR signalling for antifungal drug development, as TOR is a highly conserved master regulator of various cellular processes, including ribosome biogenesis, metabolic pathways and stress responses83.”

What the sources say

• Not checked yetcites [83] Bahn, Y. S. & Jung, K. W. Stress signaling pathways for the pathogenicity of Cryptococcus. Eukaryot. Cell 12, 1564–1577 (2013). source

In the paper

“During infection, extracellular enzymes (such as lipases, proteases and DNases) are secreted by Cryptococcus cells to damage host tissue, promote virulence and interfere with the immune response58.”

What the sources say

• Not checked yetcites [58] Almeida, F., Wolf, J. M. & Casadevall, A. Virulence-associated enzymes of Cryptococcus neoformans. Eukaryot. Cell 14, 1173–1185 (2015). source

In the paper

“A screen of compounds that specifically inhibit melanization found a new role for the pyrimidine analogue flucytosine in inhibiting pigmentation in a DNA polymerase β-dependent manner68.”

What the sources say

• Not checked yetcites [68] Zimbres, A. C. G. et al. Pharmacological inhibition of pigmentation in Cryptococcus. FEMS Yeast Res. 19, foy119 (2019).

In the paper

“This includes genes involved in the synthesis of β-1,6-glucan (such as KRE5, KRE6 and SKN1)61, the protective pigment melanin (such as the laccase gene LAC1)62, chitin in the cell wall (including the chitin synthase gene CHS3 and the regulator protein gene CSR2)63 and chitosan (exemplified by the chitin deacetylase genes CDA1, CDA2 and CDA3)64,65.”

What the sources say

• Not checked yetcites [61] Gilbert, N. M. et al. KRE genes are required for β-1,6-glucan synthesis, maintenance of capsule architecture and cell wall protein anchoring in Cryptococcus neoformans. Mol. Microbiol. 76, 517–534 (2010). source
• Not checked yetcites [62] Zhu, X., Gibbons, J., Garcia-Rivera, J., Casadevall, A. & Williamson, P. R. Laccase of Cryptococcus neoformans is a cell wall-associated virulence factor. Infect. Immun. 69, 5589–5596 (2001). source
• Not checked yetcites [63] Banks, I. R. et al. A chitin synthase and its regulator protein are critical for chitosan production and growth of the fungal pathogen Cryptococcus neoformans. Eukaryot. Cell 4, 1902–1912 (2005). source

In the paper

“Unfortunately, these derivatives also displayed a marginal increase in their in vitro toxicity against human cells compared with mefloquine104.”

What the sources say

• Not checked yetcites [104] Montoya, M. C., Beattie, S., Alden, K. M. & Krysan, D. J. Derivatives of the antimalarial drug mefloquine are broad-spectrum antifungal molecules with activity against drug-resistant clinical isolates. Antimicrob. Agents Chemother. 64, e02331-19 (2020). source

In the paper

“APX001, alone or in combination with fluconazole, significantly decreased the fungal burden in both the lungs and the brain in a mouse model of cryptococcal infection98.”

What the sources say

• Not checked yetcites [98] Rittershaus, P. C. et al. Glucosylceramide synthase is an essential regulator of pathogenicity of Cryptococcus neoformans. J. Clin. Invest. 116, 1651–1659 (2006). source

In the paper

“A phase II clinical trial to assess the efficacy and safety of tamoxifen (300 mg daily) as an adjunct therapy to the standard therapy of amphotericin B and fluconazole for the treatment of cryptococcal meningitis (NCT03112031) has completed109; however, this trial found no therapeutic benefit of this combination compared with the standard therapy alone110.”

What the sources say

• Not checked yetcites [109] Ngan, N. T. T. et al. A randomized open label trial of tamoxifen combined with amphotericin B and fluconazole for cryptococcal meningitis. Wellcome Open Res. 4, 8 (2019). source
• Not checked yetcites [110] Day, J. Best options in cryptococcosis. 29th ECCMID https://www.escmid.org/escmid_publications/escmid_elibrary/material/?mid=70711 (2019).

In the paper

“Unfortunately, despite promising results in phase I/II clinical trials, sertraline treatment alone or in combination with amphotericin B and fluconazole did not improve patient outcomes in a phase III trial with individuals being treated for cryptococcal meningits108.”

What the sources say

• Not checked yetcites [108] Rhein, J. et al. Efficacy of adjunctive sertraline for the treatment of HIV-associated cryptococcal meningitis: an open-label dose-ranging study. Lancet Infect. Dis. 16, 809–818 (2016). source

In the paper

“In addition to employing non-traditional compound libraries for the discovery of novel antifungals, alternative high-throughput screening platforms that specifically identify fungicidal molecules have been developed91,92.”

What the sources say

• Not checked yetcites [91] Hartland, K. et al. High-throughput screen in Cryptococcus neoformans identifies a novel molecular scaffold that inhibits cell wall integrity pathway signaling. ACS Infect. Dis. 2, 93–102 (2016). source
• Not checked yetcites [92] Rabjohns, J. L. A. et al. A high-throughput screening assay for fungicidal compounds against Cryptococcus neoformans. J. Biomol. Screen. 19, 270–277 (2014). source

In the paper

“Finally, biosynthesis of sphingolipids is emerging as an attractive target given the function of these lipids in mediating signal transduction, cell regulation and virulence in fungal pathogens99.”

What the sources say

• Not checked yetcites [99] Singh, A. et al. Methylation of glycosylated sphingolipid modulates membrane lipid topography and pathogenicity of Cryptococcus neoformans. Cell Microbiol. 14, 500–516 (2012). source

In the paper

“However, evidence exists for divergence in regulation of TOR signalling in C. neoformans and other fungi85, which would have important implications for the development of a broad-spectrum antifungal therapeutic.”

What the sources say

• Not checked yetcites [85] So, Y. S., Lee, D. G., Idnurm, A., Ianiri, G. & Bahn, Y. S. The TOR pathway pays pleiotropic roles in growth and stress responses of the fungal pathogen Cryptococcus neoformans. Genetics 212, 1241–1258 (2019). source

In the paper

“The tetrazole VT-1598 is a rationally designed Erg11 inhibitor that has increased fungal selectivity compared with other approved Erg11 inhibitors, including fluconazole101”

What the sources say

• Not checked yetcites [101] Garvey, E. P., Sharp, A. D., Warn, P. A., Yates, C. M. & Schotzinger, R. J. The novel fungal CYP51 inhibitor VT-1598 is efficacious alone and in combination with liposomal amphotericin B in a murine model of cryptococcal meningitis. J. Antimicrob. Chemother. 73, 2815–2822 (2018). source

In the paper

“For example, the antimalarial compound mefloquine has limited activity against C. albicans and C. neoformans104”

What the sources say

• Not checked yetcites [104] Montoya, M. C., Beattie, S., Alden, K. M. & Krysan, D. J. Derivatives of the antimalarial drug mefloquine are broad-spectrum antifungal molecules with activity against drug-resistant clinical isolates. Antimicrob. Agents Chemother. 64, e02331-19 (2020). source

In the paper

“The Gwt1 inhibitor APX001 has demonstrated in vitro and in vivo efficacy against Cryptococcus spp.97”

What the sources say

• Not checked yetcites [97] Shaw, K. J. et al. In vitro and in vivo evaluation of APX001A/APX001 and other Gwt1 inhibitors against Cryptococcus. Antimicrob. Agents Chemother. 62, e00523-18 (2018).

In the paper

“For example, a screen with the Prestwick Chemical Library of 1,120 off-patent drugs and molecules identified 31 molecules with fungilytic activity111.”

What the sources say

• Not checked yetcites [111] Butts, A. et al. A repurposing approach identifies off-patent drugs with fungicidal cryptococcal activity, a common structural chemotype, and pharmacological properties relevant to the treatment of cryptococcosis. Eukaryot. Cell 12, 278–287 (2013). source

In the paper

“Specifically, BTUs were implicated as direct inhibitors of the Sec4-class small GTPase Sav1, leading to impaired function of the late post-Golgi secretory pathway and highlighting a unique way to compromise cell wall integrity and inhibit fungal cell growth95.”

What the sources say

• Not checked yetcites [95] Beattie, S. R. et al. Benzothiourea derivatives target the secretory pathway of the human fungal pathogen Cryptococcus neoformans. ACS Infect. Dis. 6, 529–539 (2020). source

In the paper

“For example, the Malaria Box and the Pathogen Box of Medicines for Malaria Venture, which are collections of diverse molecules that are active against malaria and neglected tropical diseases, have now been screened for molecules with activity against fungal pathogens, including C. neoformans88,89.”

What the sources say

• Not checked yetcites [88] Jung, E. H., Meyers, D. J., Bosch, J. & Casadevall, A. Novel antifungal compounds discovered in medicines for Malaria Venture’s Malaria Box. mSphere 3, e00537-17 (2018).
• Not checked yetcites [89] Mayer, F. L. & Kronstad, J. W. Discovery of a novel antifungal agent in the Pathogen Box. mSphere 2, e00120-17 (2017). source

In the paper

“Originally developed as an antidepressant, sertraline acts synergistically with fluconazole in a mouse model of systemic cryptococcosis, reducing the fungal burden105.”

What the sources say

• Not checked yetcites [105] Zhai, B., Wu, C., Wang, L., Sachs, M. S. & Lin, X. The antidepressant sertraline provides a promising therapeutic option for neurotropic cryptococcal infections. Antimicrob. Agents Chemother. 56, 3758–3766 (2012). source

In the paper

“Through this endeavour, N-substituted benzothioureas (BTUs) were highlighted as a scaffold that is capable of inhibiting activation of the cell wall integrity pathway in Cryptococcus spp.91”

What the sources say

• Not checked yetcites [91] Hartland, K. et al. High-throughput screen in Cryptococcus neoformans identifies a novel molecular scaffold that inhibits cell wall integrity pathway signaling. ACS Infect. Dis. 2, 93–102 (2016). source

In the paper

“A screen of synthetic small molecules that specifically target the synthesis of the fungal sphingolipid glucosylceramide (GluCer) identified two compounds — N′-(3-bromo-4-hydroxybenzylidene)-2-methylbenzohydrazide (BHBM) and its derivative 3-bromo-N′-(3-bromo-4-hydroxybenzylidene)benzohydrazide (B0) — as highly effective antifungal agents in multiple mouse models of cryptococcosis100”

What the sources say

• Not checked yetcites [100] Mor, V. et al. Identification of a new class of antifungals targeting the synthesis of fungal sphingolipids. mBio 6, e00647 (2015). This work identifies a new class of antifungal agents that target sphingolipids in several fungal pathogens and that display fungal-selective activity and synergism with currently used therapies.

In the paper

“Furthermore, screening a diverse collection of natural product-producing actinomycete strains led to identification of the glycosylated macrolactone ibomycin as an inhibitor of C. neoformans growth, owing to its ability to permeate the fungal cell wall and affect membrane function by disrupting endosomal trafficking90”

What the sources say

• Not checked yetcites [90] Robbins, N. et al. Discovery of ibomycin, a complex macrolactone that exerts antifungal activity by impeding endocytic trafficking and membrane function. Cell Chem. Biol. 23, 1383–1394 (2016). source

In the paper

“A high-throughput approach has been developed to predict synergistic and antagonistic drug pairs using at least one known synergistic drug pair and chemical–genetic data sets118,119.”

What the sources say

• Not checked yetcites [118] Brown, J. C. S. et al. Unraveling the biology of a fungal meningitis pathogen using chemical genetics. Cell 159, 1168–1187 (2014). This work establishes a chemical–genetic platform providing an approach to explore antifungal activities of novel compounds and predict synergistic antifungal combinations that are effective against Cryptococcus spp. source
• Not checked yetcites [119] Wambaugh, M. A. et al. Synergistic and antagonistic drug interactions in the treatment of systemic fungal infections. eLife 9, e54160 (2020). source

In the paper

“Indeed, the combination of these drugs displayed enhanced efficacy in a mouse model of cryptococcal meningitis119.”

What the sources say

• Not checked yetcites [119] Wambaugh, M. A. et al. Synergistic and antagonistic drug interactions in the treatment of systemic fungal infections. eLife 9, e54160 (2020). source

In the paper

“This is illustrated by inhibitors of Hsp90, calcineurin and other stress response regulators, which show promise in combination with azoles for inhibiting Cryptococcus spp. growth76,79,80.”

What the sources say

• Not checked yetcites [76] Juvvadi, P. R., Lamoth, F. & Steinbach, W. J. Calcineurin as a multifunctional regulator: unraveling novel functions in fungal stress responses, hyphal growth, drug resistance, and pathogenesis. Fungal Biol. Rev. 28, 56–69 (2014). source
• Not checked yetcites [79] Chatterjee, S. & Tatu, U. Heat shock protein 90 localizes to the surface and augments virulence factors of Cryptococcus neoformans. PLoS Negl. Trop. Dis. 11, e0005836 (2017). source
• Not checked yetcites [80] Cordeiro, R. A. et al. Inhibition of heat-shock protein 90 enhances the susceptibility to antifungals and reduces the virulence of Cryptococcus neoformans/Cryptococcus gattii species complex. Microbiology 162, 309–317 (2016). source

In the paper

“Administration of 18B7 was safe and transiently reduced serum antigen levels at high doses but exhibited poor cerebrospinal fluid penetration132.”

What the sources say

• Not checked yetcites [132] Larsen, R. A. et al. Phase I evaluation of the safety and pharmacokinetics of murine-derived anticryptococcal antibody 18B7 in subjects with treated cryptococcal meningitis. Antimicrob. Agents Chemother. 49, 952–958 (2005). source

In the paper

“In addition to cell-mediated immunity, pioneering work established that a monoclonal antibody specific for the C. neoformans polysaccharide capsule was protective against cryptococcal infection in mice126,127.”

What the sources say

• Not checked yetcites [126] Dromer, F., Charreire, J., Contrepois, A., Carbon, C. & Yeni, P. Protection of mice against experimental cryptococcosis by anti-Cryptococcus neoformans monoclonal antibody. Infect. Immun. 55, 749–752 (1987). source
• Not checked yetcites [127] Dromer, F., Salamero, J., Contrepois, A., Carbon, C. & Yeni, P. Production, characterization, and antibody specificity of a mouse monoclonal antibody reactive with Cryptococcus neoformans capsular polysaccharide. Infect. Immun. 55, 742–748 (1987). This report is the first of a monoclonal antibody that provides protection against experimental cryptococcosis, challenging the long-standing dogma that antibodies are unimportant in anti-cryptococcal immunity. source

In the paper

“This immune response is mediated by the production of cytokines, including interleukin-2 (IL-2), IL-12, tumour necrosis factor (TNF) and interferon-γ (IFNγ), which in turn recruit phagocytes that help to clear the infection120,122.”

What the sources say

• Not checked yetcites [120] Wozniak, K. L. et al. Insights into the mechanisms of protective immunity against Cryptococcus neoformans infection using a mouse model of pulmonary cryptococcosis. PLoS ONE 4, e6854 (2009). source
• Not checked yetcites [122] Caballero Van Dyke, M. C. & Wormley, F. L. Jr. A call to arms: quest for a cryptococcal vaccine. Trends Microbiol. 26, 436–446 (2018). source

In the paper

“Furthermore, 18B7 behaves as a catalytic antibody that is capable of hydrolysis of the C. neoformans capsule131.”

What the sources say

• Not checked yetcites [131] Bowen, A., Wear, M. P., Cordero, R. J., Oscarson, S. & Casadevall, A. A monoclonal antibody to Cryptococcus neoformans glucuronoxylomannan manifests hydrolytic activity for both peptides and polysaccharides. J. Biol. Chem. 292, 417–434 (2017). source

In the paper

“A strong IFNγ response is indicative of a good prognosis in patients with cryptococcosis123,124.”

What the sources say

• Not checked yetcites [123] Jarvis, J. N. et al. Determinants of mortality in a combined cohort of 501 patients with HIV-associated cryptococcal meningitis: implications for improving outcomes. Clin. Infect. Dis. 58, 736–745 (2014). source
• Not checked yetcites [124] Jarvis, J. N. et al. Adjunctive interferon-γ immunotherapy for the treatment of HIV-associated cryptococcal meningitis: a randomized controlled trial. AIDS 26, 1105–1113 (2012). source

In the paper

“Administration of 18B7 was safe and transiently reduced serum antigen levels at high doses but exhibited poor cerebrospinal fluid penetration132.”

What the sources say

• Not checked yetcites [132] Larsen, R. A. et al. Phase I evaluation of the safety and pharmacokinetics of murine-derived anticryptococcal antibody 18B7 in subjects with treated cryptococcal meningitis. Antimicrob. Agents Chemother. 49, 952–958 (2005). source

In the paper

“Two phase II clinical trials investigated the safety and efficacy of administering exogenous, recombinant IFNγ as a cryptococcal therapy and found that addition of adjuvant IFNγ to the standard of care enhanced fungal clearance from the cerebrospinal fluid with no reported increase in adverse effects124,125.”

What the sources say

• Not checked yetcites [124] Jarvis, J. N. et al. Adjunctive interferon-γ immunotherapy for the treatment of HIV-associated cryptococcal meningitis: a randomized controlled trial. AIDS 26, 1105–1113 (2012). source
• Not checked yetcites [125] Pappas, P. G. et al. Recombinant interferon-γ1b as adjunctive therapy for AIDS-related acute cryptococcal meningitis. J. Infect. Dis. 189, 2185–2191 (2004). source

In the paper

“18B7 is capable of modulating C. neoformans gene expression and metabolism, resulting in increased susceptibility to antifungal drugs130.”

What the sources say

• Not checked yetcites [130] McClelland, E. E., Nicola, A. M., Prados-Rosales, R. & Casadevall, A. Ab binding alters gene expression in Cryptococcus neoformans and directly modulates fungal metabolism. J. Clin. Invest. 120, 1355–1361 (2010). source

In the paper

“Subsequent studies to identify compounds that augment amphotericin B and fluconazole activity against Cryptococcus spp. also identified numerous antipsychotic drugs, including sertraline, trifluoperazine and thioridazine112,113.”

What the sources say

• Not checked yetcites [112] Spitzer, M. et al. Cross-species discovery of syncretic drug combinations that potentiate the antifungal fluconazole. Mol. Syst. Biol. 7, 499 (2011). source
• Not checked yetcites [113] Rossi, S. A. et al. Identification of off-patent drugs that show synergism with amphotericin B or that present antifungal action against Cryptococcus neoformans and Candida spp. Antimicrob. Agents Chemother. 64, e01921-19 (2020). source

In the paper

“Several β-lactam antibiotics were identified as antagonistic with fluconazole in C. neoformans, an important consideration given that susceptible patient populations often have comorbidities119.”

What the sources say

• Not checked yetcites [119] Wambaugh, M. A. et al. Synergistic and antagonistic drug interactions in the treatment of systemic fungal infections. eLife 9, e54160 (2020). source

In the paper

“Chemical–genetic mapping of synergistic compound pairs has been explored in Saccharomyces cerevisiae, but pathogen-specific analyses have revealed that many compounds display species-specific chemical–genetic interactions118.”

What the sources say

• Not checked yetcites [118] Brown, J. C. S. et al. Unraveling the biology of a fungal meningitis pathogen using chemical genetics. Cell 159, 1168–1187 (2014). This work establishes a chemical–genetic platform providing an approach to explore antifungal activities of novel compounds and predict synergistic antifungal combinations that are effective against Cryptococcus spp. source

In the paper

“A study assessing the combination of known antifungals with ~3,600 bioactive compounds identified clofazimine as a broad-spectrum adjuvant therapy that is capable of acting synergistically with both caspofungin and fluconazole against C. neoformans, among other fungal species115”

What the sources say

• Not checked yetcites [115] Robbins, N. et al. An antifungal combination matrix identifies a rich pool of adjuvant molecules that enhance drug activity against diverse fungal pathogens. Cell Rep. 13, 1481–1492 (2015). source

In the paper

“Analysis of the chemical structures of drugs with anti-cryptococcal activity revealed a general structure comprising a hydrophobic or lipophilic moiety linked to a cationic amine substituent111.”

What the sources say

• Not checked yetcites [111] Butts, A. et al. A repurposing approach identifies off-patent drugs with fungicidal cryptococcal activity, a common structural chemotype, and pharmacological properties relevant to the treatment of cryptococcosis. Eukaryot. Cell 12, 278–287 (2013). source

In the paper

“Studies in animal models have emphasized the importance of CD4+ T cell-mediated immunity (particularly T helper 1 cells) in protection against cryptococcosis120,121.”

What the sources say

• Not checked yetcites [120] Wozniak, K. L. et al. Insights into the mechanisms of protective immunity against Cryptococcus neoformans infection using a mouse model of pulmonary cryptococcosis. PLoS ONE 4, e6854 (2009). source
• Not checked yetcites [121] Hole, C. R. & Wormley, F. L. Jr Vaccine and immunotherapeutic approaches for the prevention of cryptococcosis: lessons learned from animal models. Front. Microbiol. 3, 291 (2012).

In the paper

“It has become increasingly evident that interactions between Cryptococcus spp. and host immune responses dictate disease progression4, demanding a greater understanding of pathogen–host immune interactions.”

What the sources say

• Not checked yetcites [4] Perfect, J. R. et al. Clinical practice guidelines for the management of cryptococcal disease: 2010 update by the Infectious Diseases Society of America. Clin. Infect. Dis. 50, 291–322 (2010). source

In the paper

“A well-characterized example is 18B7, a mouse-derived monoclonal antibody directed against glucuronoxylomannan, the primary component of the C. neoformans polysaccharide capsule129”

What the sources say

• Not checked yetcites [129] Casadevall, A. et al. Characterization of a murine monoclonal antibody to Cryptococcus neoformans polysaccharide that is a candidate for human therapeutic studies. Antimicrob. Agents Chemother. 42, 1437–1446 (1998). source

In the paper

“Administration of 18B7 was safe and transiently reduced serum antigen levels at high doses but exhibited poor cerebrospinal fluid penetration132.”

What the sources say

• Not checked yetcites [132] Larsen, R. A. et al. Phase I evaluation of the safety and pharmacokinetics of murine-derived anticryptococcal antibody 18B7 in subjects with treated cryptococcal meningitis. Antimicrob. Agents Chemother. 49, 952–958 (2005). source

In the paper

“For example, the overlap2 method was applied to a compound library enriched for FDA-approved compounds against C. neoformans116–119 and successfully predicted that the anticholinergic drug dicyclomine HCl with fluconazole would serve as a potent anti-cryptococcal combination therapy.”

What the sources say

• Not checked yetcites [116] Wambaugh, M. A. & Brown, J. C. S. High-throughput identification of synergistic drug combinations by the overlap2 method. J. Vis. Exp. 135, 57241 (2018).
• Not checked yetcites [117] Wambaugh, M. A., Shakya, V. P. S., Lewis, A. J., Mulvey, M. A. & Brown, J. C. S. High-throughput identification and rational design of synergistic small-molecule pairs for combating and bypassing antibiotic resistance. PLoS Biol. 15, e2001644 (2017). source
• Not checked yetcites [118] Brown, J. C. S. et al. Unraveling the biology of a fungal meningitis pathogen using chemical genetics. Cell 159, 1168–1187 (2014). This work establishes a chemical–genetic platform providing an approach to explore antifungal activities of novel compounds and predict synergistic antifungal combinations that are effective against Cryptococcus spp. source
• Not checked yetcites [119] Wambaugh, M. A. et al. Synergistic and antagonistic drug interactions in the treatment of systemic fungal infections. eLife 9, e54160 (2020). source

In the paper

“Glucan particles generated from acapsular mutant strains of C. neoformans and C. gattii show great promise as a delivery system and adjuvant for cryptococcal vaccines138.”

What the sources say

• Not checked yetcites [138] Specht, C. A. et al. Vaccination withrecombinant Cryptococcus proteins in glucan particles protects mice against cryptococcosis in a manner dependent upon mouse atrain and cryptococcal species. mBio 8, e01872-17 (2017). source

In the paper

“Given that co-infections with C. neoformans and other pathogens represent a significant risk factor for the development of immune reconstitution inflammatory syndrome, this adverse reaction needs to be carefully monitored when advancing novel immunotherapies.”

What the sources say

• Not checked yetcites [139] Barber, D. L., Andrade, B. B., Sereti, I. & Sher, A. Immune reconstitution inflammatory syndrome: the trouble with immunity when you had none. Nat. Rev. Microbiol. 10, 150–156 (2012). source

In the paper

“Furthermore, immunocompetent mice immunized with H99γ that were subsequently depleted of both CD4+ T cells and CD8+ T cells were protected upon challenge with wild-type C. neoformans133.”

What the sources say

• Not checked yetcites [133] Wozniak, K. L., Young, M. L. & Wormley, F. L. Jr Protective immunity against experimental pulmonary cryptococcosis in T cell-depleted mice. Clin. Vaccine Immunol. 18, 717–723 (2011). source

In the paper

“For example, immunization with a heat-killed C. neoformans mutant for the F-box protein Fbp1 (HK-fbp1) resulted in protection against Cryptococcus infection in mice depleted of CD4+ T cells137.”

What the sources say

• Not checked yetcites [137] Wang, Y., Wang, K., Masso-Silva, J. A., Rivera, A. & Xue, C. A heat-killed Cryptococcus mutant atrain induces host protection against multiple invasive mycoses in a murine vaccine model. mBio 10, e02145-19 (2019).

In the paper

“Interestingly, in a mouse model of cryptococcosis, immunization with a C. neoformans strain that was genetically engineered to produce IFNγ (H99γ) induced protective immunity in mice depleted of CD4+ T cells133,134.”

What the sources say

• Not checked yetcites [133] Wozniak, K. L., Young, M. L. & Wormley, F. L. Jr Protective immunity against experimental pulmonary cryptococcosis in T cell-depleted mice. Clin. Vaccine Immunol. 18, 717–723 (2011). source
• Not checked yetcites [134] Wormley, F. L. Jr., Perfect, J. R., Steele, C. & Cox, G. M. Protection against cryptococcosis by using a murine γ interferon-producing Cryptococcus neoformans strain. Infect. Immun. 75, 1453–1462 (2007). source