Hui-Ying Jiang

The Epidemiological, Clinical, and Laboratory Features of Sporadic Creutzfeldt-Jakob Disease Patients in China: Surveillance Data from 2006 to 2010

Background Creutzfeldt-Jakob disease (CJD) is a rare, rapidly progressive fatal central nervous system disorder, which consists of three main catalogues: sporadic, familial, and iatrogenic CJD. Methodology/Principal Findings In China, the surveillance for CJD started in 2006, covering 12 provincial Centers for Disease Control and Prevention (CDCs) and 15 hospitals. From 2006 to 2010, 624 suspected patients were referred to China CJD surveillance. The epidemiological, clinical and laboratory features of sporadic CJD (sCJD) were analysed. Both groups of probable and possible sCJD showed highest incidences in the population of 60 to 69 year-olds. The most common presenting symptoms were progressive dementia and mental-related symptoms (neurological symptoms including sleeping turbulence, depression, anxiety and stress). Among the four main clinical manifestations, myoclonus was more frequently observed in the probable sCJD patients. About 2/3 of probable sCJD cases showed positive 14-3-3 in CSF and/or periodic sharp wave complexes (PSWC) in electroencephalography (EEG). The presence of myoclonus was significantly closely related with the appearance of PSWC in EEG. Polymorphisms of codon 129 in PRNP of the notified cases revealed a highly predominant M129M genotype in Han Chinese. Among 23 genetic human prion diseases, ten were D178N/M129M Fatal familial insomnia (FFI) and five were T188K genetic CJD (gCJD), possibly indicating a special distribution of gCJD-related mutations in Han Chinese. Conclusion From the period of 2006 to 2010, 261 patients were diagnosed as sCJD and 23 patients were diagnosed as genetic human prion diseases in China. The epidemiological, clinical and laboratory analysis data were consistent with the characteristics of sporadic CJD, which provide insight into the features of CJD in China.

Surveillance for Creutzfeldt-Jakob disease in China from 2006 to 2007

BackgroundHuman transmissible spongiform encephalopathies (HTSE), or Creutzfeldt-Jakob disease (CJD), is a group of rare and fatal diseases in central nervous system. Since outbreak of bovine spongiform encephalopathy (BSE) and variant CJD, a worldwide CJD surveillance network has been established under the proposition of WHO. In China, a national CJD surveillance system has started since 2002. The data of CJD surveillance from 2006 to 2007 was analyzed.MethodsTotal 12 provinces are included in CJD surveillance system. The surveillance unit in each province consists of one or two sentinel hospitals and the provincial CDC. All suspected CJD cases reported from CJD surveillance were diagnosed and subtyped based on the diagnostic criteria for CJD issued by WHO.ResultsTotal 192 suspected CJD cases were reported and 5 genetic CJD, 51 probable and 30 possible sporadic CJD (sCJD) cases were diagnosed. The collected sCJD cases distribute sporadically without geographical clustering and seasonal relativity and the highest incidences in both probable and possible sCJD cases appeared in the group of 60–69 year. The most common three foremost symptoms were progressive dementia, cerebellum and mental-related symptoms. The probable sCJD patients owning both typical EEG alteration and CSF protein 14-3-3 positive have more characteristic clinical syndromes than the ones having only one positive. The polymorphisms of codon 129 of all tested reported cases shows typical patterns of Han Chinese as previous reports, that M129M are predominant whereas M129V are seldom.ConclusionChinese CJD patients possessed similar epidemiological and clinical characteristics as worldwide.

Elevated levels of tau protein in cerebrospinal fluid of patients with probable Creutzfeldt-Jakob disease.

Introduction:A definitive diagnosis of Creutzfeldt–Jakob disease (CJD) can only be made by neuropathologic examination and demonstration of typical pathologic changes and the pathologic prion protein in central nervous tissues. This study investigated the diagnostic sensitivity and specificity of the microtubule-association protein tau in cerebrospinal fluid (CSF) from Chinese patients with sporadic CJD. Methods:Two hundred two CSF samples from clinically suspected patients with sporadic CJD were analyzed for tau protein by enzyme-linked immunosorbent assay and for the signal transduction regulatory protein 14-3-3 protein by immunoblot. Results:Remarkably increased levels of tau protein and increased incidence of 14-3-3 positivity were observed in probable CJD, when compared with possible CJD and others. With a threshold of 1400 pg/mL, tau determination showed a sensitivity of 90% and a specificity of 94% for the diagnosis of probable CJD. The combination of raised tau and positive 14-3-3 increased the specificity but slightly reduced the sensitivity. Statistical analysis indicated that the raised level of tau positively correlated with the presence of 14-3-3 in CSF but not with other main clinical features, eg, age, gender, clinical manifestations and sampling time. Conclusions:These data suggest that Chinese patients with probable CJD have similar increased levels of tau in the CSF as in Caucasian patients. Measurement of CSF tau will be another potential technique for antemortem CJD diagnosis.

PrP mutants with different numbers of octarepeat sequences are more susceptible to the oxidative stress

One of the physiological functions of cellular prion protein (PrPC) is believed to work as a cellular resistance to oxidative stress, in which the octarepeats region within PrP plays an important role. However, the detailed mechanism is less clear. In this study, the expressing plasmids of wild-type PrP (PrP-PG5) and various PrP mutants containing 0 (PrP-PG0), 9 (PrP-PG9) and 12 (PrP-PG12) octarepeats were generated and PrP proteins were expressed both in E. coli and in mammalian cells. Protein aggregation and formation of carbonyl groups were clearly seen in the recombinant PrPs expressed from E. coli after treatment of H2O2. MTT and trypan blue staining assays revealed that the cells expressing the mutated PrPs within octarepeats are less viable than the cells expressing wild-type PrP. Statistically significant high levels of intracellular free radicals and low levels of glutathione peroxidase were observed in the cells transfected with plasmids containing deleted or inserted octarepeats. Remarkably more productions of carbonyl groups were detected in the cells expressing PrPs with deleted and inserted octarepeats after exposing to H2O2. Furthermore, cells expressing wild-type PrP showed stronger resistant activity to the challenge of H2O2 at certain extent than the mutated PrPs and mock. These data provided the evidences that the octarepeats number within PrP is critical for maintaining its activity of antioxidation. Loss of its protective function against oxidative stress may be one of the possible pathways for the mutated PrPs to involve in the pathogenesis of familial Creutzfeldt-Jacob diseases.

Human Prion disease with a T188K mutation in Chinese: a case report

Inherited Prion diseases are characterized by mutations in the PRNP gene predispose to disease by causing the expression of abnormal PrP protein. We report a 58-year-old Chinese female with mutation in codon 188 (T188K) of the PRNP gene, while the codon 129 was a methionine homozygous genotype. The patient displayed 4-year long slowly progressive sleeping disturbance and rapid exacerbation of neurological status after other neurological manifestations appeared. Cerebral spinal fluid 14-3-3 protein was positive.

HPV-2 isolates from patients with huge verrucae vulgaris possess stronger promoter activities.

Objectives: To assess the influences of the mutations within the long control region (LCR) and E2 open reading frame (ORF) of the human papillomavirus-2 (HPV-2) isolates from patients with extensive verrucae vulgaris with cutaneous horns in the activities of the viral early promoters. Methods: A PCR method was applied for screening HPV DNA in the lesion specimens and the complete HPV-2 genomes was analyzed. Recombinant CAT-reporter plasmids containing various HPV-2 LCRs and mammalian expression plasmids containing E2 ORF were constructed. The promoter activity was evaluated by transient transfection. Results: The whole HPV-2 genomes were obtained from both patients. Several mutations in LCR and mutations leading to alterations of amino acids in E2 protein were identified in isolate-1, while a few point mutations in LCR were seen in isolate-2. Under the control of LCRs, the viral early promoter activities of isolate-1 and isolate-2 were increased 3- and 2-fold, respectively. Alterations of amino acids in E2 protein of isolate-1 partially abolished its promoter repressive activity. Compared with that of prototype HPV-2, the promoter activity of isolate-1 in the presence of its E2-expressing plasmid was significantly increased. Conclusions: The increased promoter activities might be linked, at least partially, to the clinical phenotypes of the uncommon huge verrucae vulgaris.

Molecular epidemiological study on prevalence of human papillomaviruses in patients with common warts in Beijing area.

OBJECTIVE To study the circulation, distribution, and genomic diversity of HPVs in common warts in Beijing area of China. METHODS Forty eight patients with pathologically diagnosed common warts were screened for the presence of HPV with HPV type-specific PCR and direct sequencing analysis. The genomic diversity of HPVs prevalent in Chinese patients was analyzed based on LCR. RESULTS Forty one (85.5%) samples were positive for HPV DNA, 13 (31.7%)--HPV-57, 12 (29.3%)--HPV-1a, 7 (17%)--HPV-27 and 5(12.2%)--HPV-2a. Four cases were infected with two different HPV types, two (4.9%) with HPV-1a and HPV-27, one (2.4%) with HPV-1 and HPV-57 and one (2.4%) with HPV-27 and HPV-57. In contrast to the prevalence of single strain of novel HPV-57 variant and HPV-1 prototype, two HPV-2 and three HPV-27 novel variants were found to circulate in Beijing. CONCLUSION HPV-1, -2, -27 and -57 are predominantly prevalent in patients with common warts in Beijing.

Transient expressions of doppel and its structural analog prionΔ32-121 in SH-SY5Y cells caused cytotoxicity possibly by triggering similar apoptosis pathway

Doppel (Dpl) is a recently identified prion (PrP)-like protein due to the structural and biochemical similarities, however, its natural function and pathogenic role in neurodegenerative diseases remains unclear. To investigate the possible pathogenic pathway of Dpl and its structural analog for cell apoptosis, mammalian expressing recombinant plasmids containing human PRND gene encoding the full-length Dpl and a truncated human PRNP gene deleting the sequences encoding the peptide from aa 32 to 121 (PrPΔ32-121) were generated. MTT assays showed the cell viabilities of the human neuroblastoma cell line SH-SY5Y receiving Dpl and PrPΔ32-121 expressing plasmids were remarkably lower. Obvious apoptosis phenomena were observed to be associated with the cells transient expressing Dpl and PrPΔ32-121, including reduced mitochondrial transmembrane potential (ψm), decreased pro-caspase-3 quantity, more numbers of annexin V- and annexin V/PI-double-stained cells and depressed Bcl-2 level. Moreover, we also found that the Dpl- and PrPΔ32-121-induced cytotoxicities and relevant apoptotic events in SH-SY5Y cells could be fully antagonized by co-expression of the human full-length PrP. These data highly indicate that cytotoxicity induced by the expression of Dpl and truncated PrP in neural derived cells are closely related with the apoptosis process, probably triggering the mitochondrial pathway. It also implies that the cell-benefit activity of the full-length PrP may result from its anti-apoptosis capacity.

A point mutation in the DNA-binding domain of HPV-2 E2 protein increases its DNA-binding capacity and reverses its transcriptional regulatory activity on the viral early promoter

BackgroundThe human papillomavirus (HPV) E2 protein is a multifunctional DNA-binding protein. The transcriptional activity of HPV E2 is mediated by binding to its specific binding sites in the upstream regulatory region of the HPV genomes. Previously we reported a HPV-2 variant from a verrucae vulgaris patient with huge extensive clustered cutaneous, which have five point mutations in its E2 ORF, L118S, S235P, Y287H, S293R and A338V. Under the control of HPV-2 LCR, co-expression of the mutated HPV E2 induced an increased activity on the viral early promoter. In the present study, a series of mammalian expression plasmids encoding E2 proteins with one to five amino acid (aa) substitutions for these mutations were constructed and transfected into HeLa, C33A and SiHa cells.ResultsCAT expression assays indicated that the enhanced promoter activity was due to the co-expressions of the E2 constructs containing A338V mutation within the DNA-binding domain. Western blots analysis demonstrated that the transiently transfected E2 expressing plasmids, regardless of prototype or the A338V mutant, were continuously expressed in the cells. To study the effect of E2 mutations on its DNA-binding activity, a serial of recombinant E2 proteins with various lengths were expressed and purified. Electrophoresis mobility shift assays (EMSA) showed that the binding affinity of E2 protein with A338V mutation to both an artificial probe with two E2 binding sites or HPV-2 and HPV-16 promoter-proximal LCR sequences were significantly stronger than that of the HPV-2 prototype E2. Furthermore, co-expression of the construct containing A338V mutant exhibited increased activities on heterologous HPV-16 early promoter P97 than that of prototype E2.ConclusionsThese results suggest that the mutation from Ala to Val at aa 338 is critical for E2 DNA-binding and its transcriptional regulation.

Generation of genetic engineering monoclonal antibodies against prion protein.

Two strains of Fab monoclonal antibodies (mAbs) against prion protein, designated as IV-66 and IV-78, were selected from the phage display libraries. The gene sequences encoding the light κ chain and heavy Fd chain of IV-78 were inserted into a baculovirus expression cassette vector for mouse IgG expression. Western blot, Dot-ELISA and immunoprecipitation confirmed that these Fab and IgG mAbs reacted well with the recombinant hamster and human PrP proteins expressed in prokaryotic and in mammalian cells and PrPSc from scrapie-infected hamsters. It demonstrates that mAbs against prion protein are successfully generated by phage-display technique.