Dataset Information

Immunoproteomic analysis of antibody responses to extracellular proteins of Candida albicans in serum of candidemia patients revealed glycosylation effects on protein antigen recognition

ABSTRACT: During infection the yeast Candida albicans undergoes a yeast-to-hyphal transition and secretes numerous proteins required for the invasion and damage of host tissues and the modulation of the host immune responses. Still little is known about the interplay of Candida albicans secreted proteins and the host adaptive immune system. For the characterization of the extracellular proteins of C. albicans and their ability to trigger a serological response in candidemia patients we applied 2D gel electrophoresis and LC-MS/MS-based approaches. These analyses identified the secretion of 101 different proteins from C. albicans yeast cells and 410 proteins from hyphal cells. Morphology-dependent changes of the secretome were mostly associated with proteins involved in cell wall organization, general stress response and the interplay with host immune cells. Our immunoproteomics workflow for the identification of secreted C. albicans protein antigens revealed a core set of 20 immunodominant specific anti- C. albicans protein antibodies. However, some secreted protein antigens showed cross-reactivity with sera from control groups without Candida infection. Glycoprotein staining of C. albicans hyphal secretome demonstrated that some secreted proteins are strongly glycosylated. Enzymatic deglycosylation of secreted proteins uncovered a significant contribution of glycan epitopes to the recognition of the secreted aspartyl protease Sap6 by IgG antibodies from patient sera.

INSTRUMENT(S): Q Exactive

ORGANISM(S): Candida Albicans (yeast)

SUBMITTER: Thomas Krueger

LAB HEAD: Olaf Kniemeyer

PROVIDER: PXD003201 | Pride | 2022-03-03

REPOSITORIES: Pride

ACCESS DATA

Similar Datasets

Project description:Candida albicans and Candida dubliniensis are closely related species displaying differences in virulence and genome content, therefore providing potential opportunities to identify novel C. albicans virulence genes. C. albicans gene arrays were used for comparative analysis of global gene expression in the two species in reconstituted human oral epithelium (RHE). C. albicans (SC5314) showed upregulation of hypha-specific and virulence genes within 30 min postinoculation, coinciding with rapid induction of filamentation and increased RHE damage. C. dubliniensis (CD36) showed no detectable upregulation of hypha-specific genes, grew as yeast, and caused limited RHE damage. Several genes absent or highly divergent in C. dubliniensis were upregulated in C. albicans. One such gene, SFL2 (orf19.3969), encoding a putative heat shock factor, was deleted in C. albicans. ÎÎsfl2 cells failed to filament under a range of hypha-inducing conditions and exhibited greatly reduced RHE damage, reversed by reintroduction of SFL2 into the ÎÎsfl2 strain. Moreover, SFL2 overexpression in C. albicans triggered hyphal morphogenesis. Although SFL2 deletion had no apparent effect on host survival in the murine model of systemic infection, ÎÎsfl2 strain-infected kidney tissues contained only yeast cells. These results suggest a role for SFL2 in morphogenesis and an indirect role in C. albicans pathogenesis in epithelial tissues. Global gene expression in Candida albicans SC5314 or Candida dubliniensis CD36 on reconstituted human oral epithelium (RHE) 30 min postinoculation. Gene expression on RHE was compared to gene expression in cells used as inoculum (0 min). Performed in three biological replicates with dye swaps across the biological replicates. Gene expression of Candida cells on RHE was normalized to gene expression in reference control (0 min); log2 ratios were calculated by dividing spot intensity of experimental by that of the reference control.

Project description:Candida albicans and Candida dubliniensis are closely related species displaying differences in virulence and genome content, therefore providing potential opportunities to identify novel C. albicans virulence genes. C. albicans gene arrays were used for comparative analysis of global gene expression in the two species in reconstituted human oral epithelium (RHE). C. albicans (SC5314) showed upregulation of hypha-specific and virulence genes within 30 min postinoculation, coinciding with rapid induction of filamentation and increased RHE damage. C. dubliniensis (CD36) showed no detectable upregulation of hypha-specific genes, grew as yeast, and caused limited RHE damage. Several genes absent or highly divergent in C. dubliniensis were upregulated in C. albicans. One such gene, SFL2 (orf19.3969), encoding a putative heat shock factor, was deleted in C. albicans. ÎÎsfl2 cells failed to filament under a range of hypha-inducing conditions and exhibited greatly reduced RHE damage, reversed by reintroduction of SFL2 into the ÎÎsfl2 strain. Moreover, SFL2 overexpression in C. albicans triggered hyphal morphogenesis. Although SFL2 deletion had no apparent effect on host survival in the murine model of systemic infection, ÎÎsfl2 strain-infected kidney tissues contained only yeast cells. These results suggest a role for SFL2 in morphogenesis and an indirect role in C. albicans pathogenesis in epithelial tissues. Global gene expression in Candida albicans SC5314 or Candida dubliniensis CD36 on reconstituted human oral epithelium (RHE) 90 min postinoculation. Gene expression on RHE was compared to gene expression on polycarbonate filter (PCF; used as RHE support matrix) 90 min postinoculation. Performed in two biological replicates with reciprocal dye swaps for each biological replicate. Gene expression of Candida cells on RHE was normalized to gene expression in reference control (PCF); log2 ratios were calculated by dividing spot intensity of experimental by that of the reference control.

Dataset Information

Immunoproteomic analysis of antibody responses to extracellular proteins of Candida albicans in serum of candidemia patients revealed glycosylation effects on protein antigen recognition

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure