Genome and molecular characterization of a CSFV strain isolated from a CSF outbreak in South China.

In the present study, the full-length nucleotide sequences of the CSFV-GZ-2009 strain of classical swine fever virus (CSFV) isolated from a hog pen in Guangdong province in China was determined. Results demonstrated that the genome of CSFV-GZ-2009 is 12,298 nucleotides (nt) in length, is composed of a 373-nt 5'-untranslated region (UTR), has an 11,697-nt open reading frame encoding a polyprotein of 3,898 amino acids, and has a 228-nt 3'-UTR. Genome comparison of the CSFV-GZ-2009 isolate (GenBank accession No. HQ380231) with other CSFV strains was also analyzed. Gene regions from CSFV-GZ-2009 and other known strains were shown to share 92.7-96.7% identity at the nucleotide level and 94.7-99.2% identity at the amino acid level. Phylogenetic analysis of the full-length genome and the following regions E(rns), E2 and NS5B revealed that the CSFV-GZ-2009 isolate was classified within subgroup 1.1 of group I and closely related to the highly virulent strain JL1 (06), cF114, Shimen and SWH with pairwise distances of 0.0037, 0.0043, 0.0058 and 0.0107, respectively. Analysis of recombination with the SimPlot program demonstrated that strain CSFV-GZ-2009 was not a naturally homologous recombinant. Furthermore, the change of clinical signs of pigs after infection of CSFV-GZ-2009 isolates showed typical symptoms such as diarrhea, persistent fever, and mononuclear lymphocytopenia after CSFV infection. Based on phylogenetic analysis and an animal infection test, we could conclude that the CSFV-GZ-2009 isolate belonged to subgroup 1.1 of group I and was of high virulence.

[Association of polymorphisms in signal transducer and activator of transcription 4 gene and the susceptibility to unexplained recurrent spontaneous abortions].

OBJECTIVE: To investigate the association between the polymorphisms of signal transducer and activator of transcription 4 (STAT4) gene and the susceptibility to unexplained recurrent spontaneous abortion(URSA). METHODS: PCR-restriction fragment length polymorphism (PCR-RFLP) was used to detect genotype 3 loca (rs7574865 G/T, rs10181656 C/G and rs16833431 C/T) polymorphism of STAT4 in 246 URSA cases (URSA group) and 183 normal controls (control group) . RESULTS: (1)The frequencies of rs7574865 were genotype G/G of 36.2% (89/246) in URSA group and 46.4% (85/183) in control group, genotype G/T of 47.2% (116/246) in URSA group and 45.4% (83/183) in control group, and genotype T/T of 16.7% (41/246) in URSA group and 8.2% (15/183) in control group, which reached statistical difference (P < 0.05). The frequencies of rs10181656 were genotype CC of 36.6% (90/246) in URSA group and 46.4% (85/183) in control group, genotype C/G of 48.0% (118/246) in URSA group and 44.8% (82/183) in control group, and genotype G/G of 15.4% (38/246) in URSA group and 8.7% (16/183) in control group, which reached statistical difference (P < 0.05). The carriers of rs7574865 T allele and rs10181656 G allele increased the risk of URSA (OR = 1.51, 1.44, all P < 0.05).(2) There was no different distribution in 3 genotypes (C/C, C/T, T/T) and 2 alleles (C and T) of rs16833431 C/T between URSA patients and normal controls (P = 0.43,0.48). (3) Timated haplotype frequency distribution of rs7574865 G/T and rs10181656 C/G showed haplotype G-T conferring the susceptibility to URSA (OR = 1.49, P < 0.01), but haplotype C-G could provide protection on URSA (OR = 0.68, P < 0.01). CONCLUSION: Polymorphisms of STAT4 gene might confer the susceptibility to URSA by altering STAT4 function and (or) its expression.

[Study on association of functional polymorphisms in Foxp3 gene with the susceptibility to unexplained recurrent spontaneous abortion].

OBJECTIVE: To investigate the association between the functional polymorphisms of Foxp3 gene and unexplained recurrent spontaneous abortion (URSA). METHODS: PCR-restriction fragment length polymorphism (rs3761548, rs2294021) and PCR with sequence-specific primers (rs2232365, rs5902434) were used to detect four polymorphisms of Foxp3 in 146 URSA cases and 112 normal controls. RESULTS: (1) The frequencies of rs3761548A/C were 10.3%, 22.3% in genotype C/C, 38.4%, 40.2% in genotype A/C and 51.4%, 37.5% in genotype A/A between URSA patients and normal controls; the frequencies of rs2232365A/G were 5.5%, 15.2% in genotype A/A, 47.9%, 50.0% in genotype A/G, 46.6%, 34.8% in genotype G/G between URSA patients and normal controls; they all reached statistical difference (P < 0.05). The carriers of rs3761548A allele and rs2232365G allele increased the risk of URSA (OR = 1.73, 1.61;all P < 0.05). (2) There was no difference in the genotypic distribution of rs5902434del/ATT polymorphism between cases and controls (P = 0.10), but the frequency of del allele in URSA was statistically increased than that of controls (71.2%, 62.5%;OR = 1.49, P = 0.04). (3) There was no different distribution in 3 genotypes (C/C, T/C, T/T) and 2 alleles (T and C) of rs2294021T/C between URSA patients and normal controls (P = 0.18 and 0.08). (4) Estimated haplotype frequency distribution of rs5902434del/ATT, rs3761548A/C and rs22323565A/G showed haplotype del-A-G conferring the susceptibility to URSA (OR = 2.51, P < 0.01) but haplotype del-C-G and ATT-A-A could provide protection on URSA (OR = 0.18, 0.22; all P < 0.01). CONCLUSION: Functional polymorphisms of Foxp3 gene could probably confer the susceptibility to URSA, by altering Foxp3 function and (or) its expression.

Adenovirus-vectored shRNAs targeted to the highly conserved regions of VP1 and 2B in tandem inhibits replication of foot-and-mouth disease virus both in vitro and in vivo.

Foot-and-mouth disease is a highly contagious and economically important disease of cloven-hoofed animals. RNA interference (RNAi) can be used as a rapid and specific antiviral approach. It was shown that treatment with recombinant adenovirus (Ad(VP1-2B)) carrying shRNAs targeted to the VP1 and 2B genes of FMDV expressed in tandem had marked antiviral effects against FMDV both in IBRS-2 cells and guinea pigs. Treatment with Ad(VP1-2B) both before and after FMDV infection was most effective in IBRS-2 cells, as the FMDV RNA transcripts could not be detected within 48 h post-challenge (hpc), and the viral RNA copy number at 72 hpc was only 0.02% of that in the positive control group. Delivery of Ad(VP1-2B) reduced significantly the susceptibility of guinea pigs to FMDV infection. All guinea pigs were protected within 3 days post challenge (dpc) when they were injected twice with the same dose of Ad(VP1-2B), and a third treatment with the same dose of Ad(VP1-2B) at 3 dpc was necessary to confer longer lasting protection (up to 6 dpc). In conclusion, application of such a adenovirus vector to inhibit more than one viral gene may be an advantageous method for prevention and therapy of FMDV infection.