Characterization of the Prion Protein in Human Urine

The presence of the prion protein (PrP) in normal human urine is controversial and currently inconclusive. This issue has taken a special relevance because prion infectivity has been demonstrated in urine of animals carrying experimental or naturally occurring prion diseases, but the actual presence and tissue origin of the infectious prion have not been determined. We used immunoprecipitation, one- and two-dimensional electrophoresis, and mass spectrometry to prove definitely the presence of PrP in human urine and its post-translational modifications. We show that urinary PrP (uPrP) is truncated mainly at residue 112 but also at other residues up to 122. This truncation makes uPrP undetectable with some commonly used antibodies to PrP. uPrP is glycosylated and carries an anchor which, at variance with that of cellular PrP, lacks the inositol-associated phospholipid moiety, indicating that uPrP is probably shed from the cell surface. The detailed characterization of uPrP reported here definitely proves the presence of PrP in human urine and will help determine the origin of prion infectivity in urine.     

TPT1 Supports Proliferation of Neural Stem/Progenitor Cells and Brain Tumor Initiating Cells Regulated by Macrophage Migration Inhibitory Factor (MIF)

Neurochemical Research - One of the key areas in stem cell research is the identification of factors capable of promoting the expansion of Neural Stem Cell/Progenitor Cells (NSPCs) and...     

New Palaearctic species of the tribe Thalassaphorurini Pomorski, 1998 (Collembola, Onychiuridae)

The paper is devoted to a taxonomic revision of the genus Sensillonychiurus Pomorski & Sveenkova, 2006. Five new species of this genus, i.e. Sensillonychiurus mirussp. n., Sensillonychiurus taimyrensissp. n., Sensillonychiurus vegaesp. n., Sensillonychiurus vitimicussp. n., and Sensillonychiurus amuricussp. n., as well as three new species of the related genus Allonychiurus Yoshii, 1995, i.e. Allonychiurus subvolinensissp. n., Allonychiurus elikoniussp. n., and Allonychiurus unisetosussp. n. are being described from various regions of Eurasia. The diagnoses of both genera are amended to include described species. Two genera, Tantulonychiurus Pomorski, 1996 and Thibaudichiurus Weiner, 1996, are treated as junior synonyms of the genus Allonychiurus. Agraphorura eisi (Rusek, 1976) is transferred to Sensillonychiurus; Tantulonychiurus volinensis (Szeptycki, 1964) and Tantulonychiurus asiaticus Babenko, 2007 to Allonychiurus. A review of morphological peculiarities of Sensillonychiurus is performed, comparisons with the other genera of Thalassaphorurini given, and a key to the known species provided.     

Sensitive detection of prion protein in human urine

Transmissible spongiform encephalopathies are a group of infectious diseases typically associated with the accumulation of a protease-resistant and beta-sheet-rich prion protein, PrPSc, in affected brains. PrPSc is an altered isoform derived from the host-encoded glycoprotein, PrPC. The expression of PrPC is the highest in brain tissue, but it can also be detected at low levels in peripheral tissue. However, it is unclear whether a significant amount of PrPC is released into body fluid and excreted into urine. We have developed a simple, rapid method for the reliable detection of PrPC in urine from normal subjects by Western blotting. Our method can easily and reliably detect PrPC in apparently healthy individuals using less than 1 ml of urine in which the amount of urinary PrPC is estimated to be in the range of low micrograms/liter.