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Dengue is an emerging mosquito-borne disease, and the use of prophylactic vaccines is still limited. We previously developed a tetravalent dengue vaccine (rMV-TDV) by a recombinant measles virus (MV) vector expressing envelope protein domain III (ED3). In this study, we used dengue-susceptible AG129 mice to evaluate the protective and/or pathogenic immune responses induced by rMV-TDV. Consistent with the previous study, rMV-TDV-immunized mice developed a significant neutralizing antibody response against all serotypes of DENV, as well as a significant IFN-γ response biased to DENV-3, compared to the vector controls. We further demonstrated that this DENV-3-specific IFN-γ response was dominated by one CD4+ T-cell epitope located in E349−363. After DENV-2 challenge, rMV-TDV-immunized mice showed a significantly lower viremia and no inflammatory cytokine increase compared to the vector controls, which had an ~100 times higher viremia and a significant increase in IFN-γ and TNF-α. As a correlate of protection, a robust memory IFN-γ response specific to DENV-2 was boosted in rMV-TDV-immunized mice after challenge. This result suggested that pre-existing DENV-3-dominated T-cell responses did not cross-react, but a DENV-2-specific IFN-γ response, which was undetectable during immunization, was recalled. Interestingly, this recalled T-cell response recognized the epitope in the same position as the E349−363 but in the DENV-2 serotype. This result suggested that immunodomination occurred in the CD4+ T-cell epitopes between dengue serotypes after rMV-TDV vaccination and resulted in a DENV-3-dominated CD4+ T-cell response. Although the significant increase in IgG against both DENV-2 and -3 suggested that cross-reactive antibody responses were boosted, the increased neutralizing antibodies and IgG avidity still remained DENV-2 specific, consistent with the serotype-specific T cell response post challenge. Our data reveal that immunodomination caused a biased T-cell response to one of the dengue serotypes after tetravalent dengue vaccination and highlight the roles of cross-reactive T cells in dengue protection.

Dengue has a major impact on global public health, and the use of dengue vaccine is very limited. In this study, we evaluated the immunogenicity and protective efficacy of a dengue vaccine made from a recombinant measles virus (MV) that expresses envelope protein domain III (ED3) of dengue-1 to 4. Following immunization with the MV-vectored dengue vaccine, mice developed specific interferon-gamma and antibody responses against dengue virus and MV. Neutralizing antibodies against MV and dengue viruses were also induced, and protective levels of FRNT50 ≥ 10 to 4 serotypes of dengue viruses were detected in the MV-vectored dengue vaccine-immunized mice. In addition, specific interferon-gamma and antibody responses to dengue viruses were still induced by the MV-vectored dengue vaccine in mice that were pre-infected with MV. This finding suggests that the pre-existing immunity to MV did not block the initiation of immune responses. By contrast, mice that were pre-infected with dengue-3 exhibited no effect in terms of their antibody responses to MV and dengue viruses, but a dominant dengue-3-specific T-cell response was observed. After injection with dengue-2, a detectable but significantly lower viremia and a higher titer of anti-dengue-2 neutralizing antibodies were observed in MV-vectored dengue vaccine-immunized mice versus the vector control, suggesting that an anamnestic antibody response that provided partial protection against dengue-2 was elicited. Our results with regard to T-cell responses and the effect of pre-immunity to MV or dengue viruses provide clues for the future applications of an MV-vectored dengue vaccine.

The synthesis, mesomorphic behavior, and optical properties of a new series of transition metal complexes 1a and 1b derived from benzoxazoles 2 are reported. The crystal and molecular structure of copper complex of 6-dodecyloxynaphthalene-2-carboxylic acid 4-(6-hexyloxybenzooxazol-2-yl)-3-hydroxyphenyl ester 1a ( n =6; m =12) was determined by means of X-ray structural analysis, and it crystallizes in the triclinic space group P -1. The geometry at copper center is perfectly square-planar, and the overall molecular shape is considered as rod-shape. All precursors 2 with shorter chains ( n =0, 1, 4) exhibited nematic, and all others with longer chains ( n =6, 7, 8, 10, 12) formed N/SmC phases. In contrast, all copper(II) complexes 1a and palladium complexes 1b formed N phase. On the other hand, the temperature range of mesophase in compound 1a was wider than those in compound 1b . The difference of the mesomorphic properties in compounds 1a and 1b was attributed to the geometry or/and the size of the metal center. The fluorescent properties of these compounds were also examined.

Dengue is the leading cause of mosquito-borne viral infections and no vaccine is available now. Envelope protein domain III (ED3) is the major target for the binding of dengue virus neutralizing antibodies; however, the ED3-specifc T-cell response is less well understood. To investigate the T-cell responses to four serotypes of dengue virus (DENV-1 to 4), we immunized mice using either a tetravalent ED3-based DNA or protein vaccine, or combined both as a DNA prime-protein boost strategy (prime-boost). A significant serotype-dependent IFN-γ or IL-4 response was observed in mice immunized with either the DNA or protein vaccine. The IFN-γ response was dominant to DENV-1 to 3, whereas the IL-4 response was dominant to DENV-4. Although the similar IgG titers for the four serotypes were observed in mice immunized with the tetravalent vaccines, the neutralizing antibody titers varied and followed the order of 2 = 3>1>4. Interestingly, the lower IFN-γ response to DENV-4 is attributable to the immunodominance change between two CD4+ T-cell epitopes; one T-cell epitope located at E349-363 of DENV-1 to 3 was more immunogenic than the DENV-4 epitope E313-327. Despite DENV-4 specific IFN-γ responses were suppressed by immunodominance change, either DENV-4-specific IFN-γ or neutralizing antibody responses were still recalled after DENV-4 challenge and contributed to virus clearance. Immunization with the prime-boost elicited both IFN-γ and neutralizing antibody responses and provided better protection than either DNA or protein immunization. Our findings shed light on how ED3-based tetravalent dengue vaccines sharpen host CD4 T-cell responses and contribute to protection against dengue virus.

Nuclear mitotic apparatus protein (NuMA), originally described as a nuclear protein, is an essential component in the formation and maintenance of mitotic spindle poles. In this study, we analyze the expression pattern and function of NuMA in mouse oocytes and early embryos. In germinal vesicle-stage oocytes, NuMA was detected both at the centrosome and in the nucleus. However, after nuclear maturation and extrusion of the first polar body, NuMA was concentrated at the broad meiotic spindle poles and at cytasters (centers of cytoplasmic microtubule asters) of mature metaphase II oocytes. Cold-induced depolymerization of microtubules appeared to disassociate NuMA foci from the cytoplasmic cytasters. During fertilization, NuMA was relocated into the re-formed male and female pronuclei. Microinjection of anti-NuMA antibody into 1 of 2 cells of 2-cell-stage embryos inhibited normal cell division. These results suggest that NuMA might play an important role in cell division during early embryonic mitosis.

To explore an optimal model of hypothetical work injury insurance scheme, which is in line with the wishes of workers, based on the problems in the implementation of work injury insurance in China and to provide useful information for relevant policy makers.Multistage cluster sampling was used to select subjects: first, 9 small, medium, and large enterprises were selected from three cities (counties) in Zhejiang Province, China according to the economic development, transportation, and cooperation; then, 31 workshops were randomly selected from the 9 enterprises. Face-to-face interviews were conducted by trained interviewers using a pre-designed questionnaire among all workers in the 31 workshops.After optimization of hypothetical work injury insurance scheme, the willingness to participate in the scheme increased from 73.87%to 80.96%; the average willingness to pay for the scheme increased from 2.21% (51.77 yuan) to 2.38% of monthly wage (54.93 Yuan); the median willingness to pay for the scheme increased from 1% to 1.2% of monthly wage, but decreased from 35 yuan to 30 yuan. The optimal model of hypothetical work injury insurance scheme covers all national and provincial statutory occupational diseases and work accidents, as well as consultations about occupational diseases. The scheme is supposed to be implemented worldwide by the National Social Security Department, without regional differences. The premium is borne by the state, enterprises, and individuals, and an independent insurance fund is kept in the lifetime personal account for each of insured individuals. The premium is not refunded in any event. Compensation for occupational diseases or work accidents is unrelated to the enterprises of the insured workers but related to the length of insurance. The insurance becomes effective one year after enrollment, while it is put into effect immediately after the occupational disease or accident occurs.The optimal model of hypothetical work injury insurance scheme actually realizes cross-regional mobility of workers, minimizes regional differences, and embodies the fairness. The proposed model will, to some extent, protect the rights and interests of enterprises, as well as the healthy rights and interests of workers when they are unemployed.

We have previously demonstrated that vaccination with a subunit dengue vaccine containing a consensus envelope domain III with aluminum phosphate elicits neutralizing antibodies against all four serotypes of dengue virus in mice. In this study, we evaluated the immunogenicity of the subunit dengue vaccine in non-human primates. After vaccination, monkeys that received the subunit vaccine with aluminum phosphate developed a significantly strong and long-lasting antibody response. A specific T cell response with cytokine production was also induced, and this correlated with the antibody response. Additionally, neutralizing antibodies against serotype 2 were detected in two of three monkeys. The increase in serotype-2-specific antibody titers and avidity observed in these two monkeys suggested that a serotype-2-biased antibody response occurs. These data provide evidence that a protective neutralizing antibody response was successfully elicited in non-human primates by the dengue subunit vaccine with aluminum phosphate adjuvant.

Small ubiquitin-like modifier (SUMO) modification is emerging as an important control in transcription regulation. Here, we show that CREB-binding protein (CBP), a versatile transcriptional coactivator for numerous transcription factors in response to diverse signaling events, can be modified by SUMO-1 at lysine residues 999, 1034, and 1057 both in vitro and in vivo . Mutation of the SUMO acceptor lysine residues either individually or in combination enhanced CBP transcriptional activity, and expression of a SUMO protease SENP2 potentiated the transcriptional activity of CBP wild-type but not its sumoylation mutant, indicating that SUMO modification negatively regulates CBP transcriptional activity. Furthermore, we demonstrated an interaction of SUMO-1-modified CBP with the transcriptional corepressor Daxx and an essential role of Daxx in mediating SUMO-dependent transcriptional regulation of CBP through histone deacetylase 2 recruitment. Together, our findings indicate that SUMO modification and subsequent recruitment of Daxx represent a previously undescribed mechanism in modulating CBP transcriptional potential.

We previously reported two novel testis-specific serine/threonine kinases, Aie1 (mouse) and AIE2 (human), that share high amino acid identities with the kinase domains of fly aurora and yeast Ipl1. Here, we report the entire intron-exon organization of the Aie1 gene and analyze the expression patterns of Aie1 mRNA during testis development. The mouse Aie1 gene spans approximately 14 kb and contains seven exons. The sequences of the exon-intron boundaries of the Aie1 gene conform to the consensus sequences (GT/AG) of the splicing donor and acceptor sites of most eukaryotic genes. Comparative genomic sequencing revealed that the gene structure is highly conserved between mouse Aie1 and human AIE2. However, much less homology was found in the sequence outside the kinase-coding domains. The Aie1 locus was mapped to mouse chromosome 7A2-A3 by fluorescent in situ hybridization. Northern blot analysis indicates that Aie1 mRNA likely is expressed at a low level on day 14 and reaches its plateau on day 21 in the developing postnatal testis. RNA in situ hybridization indicated that the expression of the Aie1 transcript was restricted to meiotically active germ cells, with the highest levels detected in spermatocytes at the late pachytene stage. These findings suggest that Aie1 plays a role in spermatogenesis.

Dengue is still an important public health problem and no dengue vaccine is available now. In this study, we characterized prime-boost vaccine regimens using heterologous and homologous dengue DNA vaccine and recombinant subunit vaccine consisted of envelope (E) protein domain III (ED III) from four serotypes of dengue virus (DENV). A broader and balanced IFN-gamma and IL-4 responses was observed in DNA-prime and subunit-boost immunized mice, compared to a narrower but strong IFN-gamma production after homologous DNA vaccination and an IL-4 only response in homologous subunit vaccine immunized mice. In addition, a significant ED III specific antibody response was detected in all immunized mice except vector control. The highest IgG titer was appeared in homologous subunit vaccine immunized mice, followed by heterologous prime-boost regimen and homologous DNA vaccine. However, that heterologous prime-boost immunized mice generated a highest neutralizing antibody than the others, suggested a better protection provided by this DNA-prime and subunit vaccine-boost regimen.