[Contribution of proteomics in medical mycology in 2014: For who? For what?]

APPLICATION OF 3-HYDROXYBUTYRATE MEASUREMENT AND PLASMA PROTEIN ELECTROPHORESIS IN THE DIAGNOSIS OF ASPERGILLOSIS IN AFRICAN PENGUINS ( SPHENISCUS DEMERSUS)

New alternative laboratory means are needed to improve the options for antemortem diagnosis of avian aspergillosis. In this study, 3-hydroxybutyrate was measured in plasma samples collected from a cohort of African penguins ( Spheniscus demersus) maintained under human care. Results were interpreted in combination with those of protein electrophoresis and compared with anti- Aspergillus antibody and galactomannan antigen detection. Overall, 3-hydroxybutyrate levels were found significantly increased in Aspergillus-diseased cases versus the control penguin group ( P = 0.002). Mean absolute concentration of β-globulins was increased >20% in samples from infected birds, and α2-globublins were also found to be significantly increased versus clinically normal controls ( P < 0.001 and P = 0.001 respectively). Of note, the α2-globulins were also significantly increased versus penguins with inflammatory (non-aspergillosis) diseases ( P = 0.001). The specificity of 3-hydroxybutyrate, β-globulins, and α2-globulins for aspergillosis was 78.6%, 79.6%, and 92.2%, respectively. Using these measures in tandem resulted in high specificity (>90%) and negative predictive value (≥80%). In contrast, anti- Aspergillus antibody and galactomannan antigen did not distinguish between infected cases and controls ( P > 0.05). This study demonstrates that basic testing in tandem with the new biomarker 3-hydroxybutyrate may provide reliable evidence for the diagnosis of aspergillosis in penguins.

Application of mass spectrometry to elucidate the pathophysiology of Encephalitozoon cuniculi infection in rabbits

Encephalitozoon cuniculi is a microsporidian species which can induce subclinical to serious disease in mammals including rabbits, a definitive natural host. The pathophysiology of infection has not been comprehensively elucidated. In this exploratory study, we utilized two mass spectrometry approaches: first, the analysis of the humoral response by profiling the microsporidian antigens as revealed by Western blot screening, and second, implementing the iTRAQ®-labeling protocol to focus on the changes within the host proteome during infection. Seven E. cuniculi proteins were identified at one-dimensional gel regions where specific seropositive reaction was observed by Western blot, including polar tube protein 3, polar tube protein 2, and for the first time reported: heat shock related 70kDa protein, polysaccharide deacetylase domain-containing protein, zinc finger protein, spore wall and anchoring disk complex protein EnP1, and translation elongation factor 1 alpha. In addition, there was a significant increase of nine host proteins in blood samples from E. cuniculi-diseased rabbits in comparison with non-diseased control subjects undergoing various inflammatory processes. This included serum paraoxonase, alpha-1-antiproteinase F precursor and alpha-1-antiproteinase S-1 which have presumptive catalytic activity likely related to infection control, and cystatin fetuin-B-type, an enzyme regulator that has been poorly studied to date. Notably, 11 proteins were found to be statistically increased in rabbits with neurological versus renal clinical presentation of E. cuniculi infection. Overall, this novel analysis based on mass spectrometry has provided new insights on the inflammatory and humoral responses during E. cuniculi infection in rabbits.