A study of the Institute of Neurological Sciences at the CNR reveals a protein called thymosin beta 4, as a specific marker for patients with CJD. The result allows to diagnose a rare but fatal disease, with very high efficiency, comparable to that currently only achieved by post-mortem examinations. Researchers at the Institute of Neurological Sciences of the National Research Council (Isn-Cnr) in Mangone (Cosenza), in collaboration with University Magna Graecia of Catanzaro, Regional Hospital of Reggio Calabria and Palermo University, have identified in the cerebrospinal fluid of patients suffering from Creutzfeldt-Jakob disease (CJD), a small protein, thymosin beta 4, as a new and highly specific marker for the disease. The result could enable a definitive diagnosis, at time possible only post mortem. "The Creutzfeldt-Jakob Disease is a human variant of the diseases by infectious particles called prions and belongs to a group of neurological diseases known as subacute spongiform encephalopathies", explains Antonio Qualtieri ISN-CNR, who led the group. "It is a rare neurodegenerative disease but that leads to a form of progressive dementia and rapidly fatal. It is caused by an abnormal conformation of the prion protein PrPC, a glycoprotein expressed in all tissues and in particular in the central nervous system. At present, there are not sufficiently specific intra-vitam markers, therefore, a definitive diagnosis is possible only postmortem, by analyzing neuropathological autopsy with immunoblotting an immunoassay methods ".
By using the cerebrospinal fluid of patients initially suspected and later confirmed to be suffering from CJD, the researchers have identified, through the analysis of mass MALDI-TOF protein profiling, a number of proteins differentially expressed compared to the control population. "Among these, the thymosin beta 4 showed particularly high levels of expression", continues Qualtieri. "The analysis was then extended to groups of patients suffering from various forms of dementia, with clinical manifestations often overlapping with CJD. The analysis of the results showed a sensitivity of 100%, (ie the totality of CJD patients showed elevated levels of thymosin), and a specificity of 98.5%. This protein represents a new intra-vitam molecular marker, "with an efficiency much higher than that of the diagnostic 14.3.3 protein, the marker currently accepted by the international diagnostic criteria," concludes the researcher. " Moreover these results show, among other things, the great potential of the proteomic analysis in biomedical field." Le Pera M, Urso E, Sprovieri T, et al. Contribution of Cerebrospinal Fluid Thymosin ²4 Levels to the Clinical Differentiation of Creutzfeldt-Jakob Disease. Arch Neurol. 2012;69(7):868-872. doi:10.1001/archneurol.2011.3558.
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