Conor J. Crawford, Livia Liporagi-Lopes, Carolina Coelho, Samuel R. Santos Junior, André Moraes Nicola, Maggie P. Wear, Raghav Vij, Stefan Oscarson* and Arturo Casadevall*,
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引用次数: 0
Abstract
Cryptococcus neoformans is a fungus classified by the World Health Organization as a critically important pathogen, which poses a significant threat to immunocompromised individuals. In this study, we present the chemical synthesis and evaluation of two semisynthetic vaccine candidates targeting the capsular polysaccharide glucuronoxylomannan (GXM) of C. neoformans. These semisynthetic glycoconjugate vaccines contain an identical synthetic decasaccharide (M2 motif) antigen. This antigen is present in serotype A strains, which constitute 95% of the clinical cryptococcosis cases. This synthetic oligosaccharide was conjugated to two proteins (CRM197 and Anthrax 63 kDa PA) and tested for immunogenicity in mice. The conjugates elicited a specific antibody response that bound to the M2 motif but also exhibited additional cross-reactivity toward M1 and M4 GXM motifs. Both glycoconjugates produced antibodies that bound to GXM in ELISA assays and to live fungal cells. Mice immunized with the CRM197 glycoconjugate produced weakly opsonic antibodies and displayed trends toward increased median survival relative to mice given a mock PBS injection (18 vs 15 days, p = 0.06). These findings indicate promise, achieving a successful vaccine demands further optimization of the glycoconjugate. This antigen could serve as a component in a multivalent GXM motif vaccine.
期刊介绍:
ACS Infectious Diseases will be the first journal to highlight chemistry and its role in this multidisciplinary and collaborative research area. The journal will cover a diverse array of topics including, but not limited to:
* Discovery and development of new antimicrobial agents — identified through target- or phenotypic-based approaches as well as compounds that induce synergy with antimicrobials.
* Characterization and validation of drug target or pathways — use of single target and genome-wide knockdown and knockouts, biochemical studies, structural biology, new technologies to facilitate characterization and prioritization of potential drug targets.
* Mechanism of drug resistance — fundamental research that advances our understanding of resistance; strategies to prevent resistance.
* Mechanisms of action — use of genetic, metabolomic, and activity- and affinity-based protein profiling to elucidate the mechanism of action of clinical and experimental antimicrobial agents.
* Host-pathogen interactions — tools for studying host-pathogen interactions, cellular biochemistry of hosts and pathogens, and molecular interactions of pathogens with host microbiota.
* Small molecule vaccine adjuvants for infectious disease.
* Viral and bacterial biochemistry and molecular biology.