Bovine viral diarrhea virus (BVDV) is a pestivirus that can establish a persistent infection in the developingfetus and has the ability to disable the production of type I interferon. In this report, we extend our previous observations that BVDV encodes a protein able to specifically block the activity of interferon regulatory factor 3 (IRF-3), a transcription factor essential for interferon promoter activation, by demonstrating that this is a property of the N-terminal protease fragment (NPro) of the BVDV polyprotein. Although BVDV infections cause relocalization of cellular IRF-3 from the cytoplasm to the nucleus early in infection, NPro blocks IRF-3 from binding to DNA. NPro has the additional property of targeting IRF-3 for polyubiquitination and subsequent destruction by cellular multicatalytic proteasomes. The autoprotease activity of NPro is not required for the inhibition of type I interferon induction or the targeting of IRF-3 for degradation.Bovine viral diarrhea virus (BVDV) has a global spread and is a major reproductive pathogen of cattle (12). BVDV, along with classical Swine fever virus (CSFV), Border disease virus of sheep, and a small number of isolates from undomesticated species, make up the genus Pestivirus in the family Flaviviridae. The viruses are positive-strand RNA viruses with a genome on the order of 12.5 kb in length. The RNA is translated into a single viral polyprotein that is processed by both viral and host proteases to either 11 or 12 polypeptides, depending on the virus biotype. BVDV is generally noncytopathogenic (ncp), although the virus associated with the development of mucosal disease in persistently infected animals is a cytopathogenic (cp) biotype. The result of infection of a susceptible host with BVDV is unusual; BVDV can cause an acute infection like other viruses, but infection of a pregnant animal can result in transmission of virus from the dam to the developing fetus, where the virus can replicate. Infection of the fetus prior to immune competence results in a failure of the fetus to control virus infection and can result in the birth of persistently infected offspring that fail to mount an acquired immune response to BVDV. These offspring then serve as a reservoir for further acute virus infection and are held to be critical for BVDV transmission in areas of endemicity.Although infection during fetal development takes place in the absence of a functional acquired immune response, viruses still have to evade innate immunity in order to establish a persistent infection; the ability of ncpBVDV to avoid the induction of interferon (IFN) seems critical in this regard (5). We and others have shown that ncpBVDV encodes an active block to type I IFN induction (3, 46), and there is evidence that ncpBVDV employs more than one mechanism to bring about this block. BVDV-infected cells are refractory to the addition of double-stranded RNA (dsRNA) to the medium. At least in part, the failure of this extracellular dsRNA to induce type I IFN can be explained by the action of the s...

The immunogenicities of candidate DNA-and modified vaccinia virus Ankara (MVA)-vectored human immunodeficiency virus (HIV) vaccines were evaluated on their own and in a prime-boost regimen in phase I clinical trials in healthy uninfected individuals in the United Kingdom. Given the current lack of approaches capable of inducing broad HIV-neutralizing antibodies, the pTHr.HIVA DNA and MVA.HIVA vaccines focus solely on the induction of cell-mediated immunity. The vaccines expressed a common immunogen, HIVA, which consists of consensus HIV-1 clade A Gag p24/p17 proteins fused to a string of clade A-derived epitopes recognized by cytotoxic T lymphocytes (CTLs). Volunteers' fresh peripheral blood mononuclear cells were tested for HIV-specific responses in a validated gamma interferon enzyme-linked immunospot (ELISPOT) assay using four overlapping peptide pools across the Gag domain and three pools of known CTL epitopes present in all of the HIVA protein. Both the DNA and the MVA vaccines alone and in a DNA prime-MVA boost combination were safe and induced HIV-specific responses in 14 out of 18, seven out of eight and eight out of nine volunteers, respectively. These results are very encouraging and justify further vaccine development.

Immunogenic cell death is characterized by damage-associated molecular patterns, which can enhance the maturation and antigen uptake of dendritic cells. Shikonin, an anti-inflammatory and antitumor phytochemical, was exploited here as an adjuvant for dendritic cell-based cancer vaccines via induction of immunogenic cell death. Shikonin can effectively activate both receptor- and mitochondria-mediated apoptosis and increase the expression of all five tested damage-associated molecular patterns in the resultant tumor cell lysates. The combination treatment with damage-associated molecular patterns and LPS activates dendritic cells to a high maturation status and enhances the priming of Th1/Th17 effector cells. Shikonin-tumor cell lysate-loaded mature dendritic cells exhibit a high level of CD86 and MHC class II and activate Th1 cells. The shikonin-tumor cell lysate-loaded dendritic cell vaccines result in a strong induction of cytotoxic activity of splenocytes against target tumor cells, a retardation in tumor growth, and an increase in the survival of test mice. The much enhanced immunogenicity and efficacy of the current cancer vaccine formulation, that is, the use of shikonin-treated tumor cells as cell lysates for the pulse of dendritic cells in culture, may suggest a new ex vivo approach for developing individualized, dendritic cells-based anticancer vaccines.

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Recent studies have revealed that an orphan receptor gene of the steroid/thyroid hormone nuclear receptor superfamily, the Nurr1 gene, is essential for the neurogenesis and differentiation of dopaminergic neurons in the midbrain of mice. Transgenic mice lacking the Nurr1 gene soon die after birth and are devoid of dopaminergic neurons in the midbrain. Heterozygous mice survive postnatally without obvious locomotor deficits; however, they have increased vulnerability to dopaminergic neurotoxin 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). In view of the importance of dopamine neurotransmission in brain function, we were interested to know if the human homologous gene of murine Nurr1, the NR4A2 gene, may play a role in the pathogenesis of schizophrenia. We systematically sequenced all the exons of the human NR4A2 gene to search for molecular variants in a cohort of Chinese schizophrenic patients from Taiwan. Two molecular variants were identified: a G-insertion in intron 6 (designated IVS6 + 17 [see text] + 18insG), and a G-deletion in the untranslated exon 1 (designated c.-469delG). The IVS6 + 17 [see text] + 18insG is a polymorphic one; further case control study, however, did not reveal association of this polymorphism with schizophrenia. The c.-469delG is a rare variant found in two unrelated patients among 177 schizophrenic patients, but not in 130 nonpsychotic controls. The result suggests that the c.-469delG and possibly other variants of the NR4A2 gene may be of relevance to the complex factors involved in the pathogenesis of schizophrenia.