OBJECTIVETo study the genome sequence of hepatitis A virus L-A-1 strain which has been applied for live attenuated vaccine production in China, to compare with other HAV strains, to understand some characteristics of L-A-1 strain, and to find the mechanism of attenuation and cell adaptation.

METHODSGenome fragments were prepared by antigen-capture PCR from infected cell (2BS), PCR products were cloned into T vector, sequenced and analyzed by using bioinformatics program.

RESULTSAnalysis of the genomic sequences(nt 25-7,418) showed that the open reading frame contains 6,675 nucleotides in length encoding 2,225 amino acids. Sequence homology comparison showed 98.00% and 94.00% homology at nucleotide level, and 98.51% and 98.65% homology at amino acid level with international strains MBB and HM 175, respectively. Through comparison with other attenuated, cell adapted and cytopathic effect (CPE) strains, L-A-1 strain had mutation at nt 152, 591, 646, 687 and insertion at nt 180-181 in 5?NTR and had mutation at nt 3,889 (aa 1 052-Val) in 2B region, these mutations and insertion are molecular basis for cell adaptation; mutation at nt 4,185 (aa 1 152-Lys) in 2C region should be attenuated marker; deletion in 3A region (nt 5,020-5,025) that caused two amino acids deletion is virus fast growth basis.

CONCLUSIONThrough analyzing L-A-1 strain genomic sequence, certain sites related to cell adaptation and attenuation were found.

Adaptation, Biological ; genetics ; Amino Acid Sequence ; Base Sequence ; Gene Deletion ; Genome, Viral ; Hepatitis A Vaccines ; genetics ; Hepatitis A virus ; genetics ; growth & development ; Mutation ; Open Reading Frames ; genetics ; Sequence Homology ; Vaccines, Attenuated ; genetics

OBJECTIVETo study the safety and immunogenicity of the Bilive combined hepatitis A and B vaccine produced by Sinovac Biotech Co., Ltd.

METHODSSamples were selected from first year students of a senior high school (adults group) and first to fifth grade 1-5 students of 3 primary schools (children group). Those who were susceptible to both hepatitis A virus (HAV) and hepatitis B virus (HBV), HAV only or HBV only were assigned to group AB, A and B respectively and were vaccinated with three doses (0, 1 and 6 month schedule) of Bilive combined hepatitis A and B vaccine, inactivated hepatitis A vaccine and recombined hepatitis B vaccine respectively. The dosage for adult group was 500 U hepatitis A antigen and/or 10 micro g hepatitis B surface antigen and the dosage for children group was half the dosage of adult group. The potential adverse effects were observed within 72 hours after vaccination. Serum samples were collected for testing anti-HAV and anti-HBs at month 2 and 7 after the initial dose.

RESULTSThe rates of local adverse effects were 0.58% and 2.56% in children AB group and adults AB group and the general adverse effects rates were 9.88% and 5.45% respectively. Both local and general adverse effect rates were not significantly different to the control group. The sero-conversion rate of anti-HAV in children and adults AB group reached 100%, one month after 3 doses. The geometric mean titer (GMTs) reached 33,910 mIU/ml and 23,435 mIU/ml respectively, significant higher than that in control group (group A). The sero-conversion rates of anti-HBs were 97.30% and 96.63%, and GMTs were 103 mIU/ml and 102 mIU/ml in children and adults AB group respectively. No significant difference on sero-conversion and GMT was observed when compared with control group.

CONCLUSIONThe Bilive combined hepatitis A and B vaccine had good safety profile, and the immunogenicity both on anti-HAV and anti-HBs was similar to that of separated components.

Adolescent ; Adult ; Child ; Female ; Hepatitis A ; prevention & control ; Hepatitis A Antibodies ; blood ; Hepatitis A Vaccines ; administration & dosage ; adverse effects ; immunology ; Hepatitis Antibodies ; blood ; Hepatitis B ; prevention & control ; Hepatitis B Antibodies ; blood ; Hepatitis B Vaccines ; administration & dosage ; adverse effects ; immunology ; Humans ; Male ; Safety ; Vaccines, Combined ; administration & dosage ; adverse effects ; immunology ; Vaccines, Synthetic ; administration & dosage ; adverse effects ; immunology

Epithelial cell adhesion molecule (EpCAM) is a popular target for cancer therapy. In this research, 3 nanobodies with high specificity and endocytosis activity against EpCAM were developed, which provides a basis for the study of immunotoxin based on EpCAM. In our preliminary experiments, we have immunized a camel with EpCAM-Fc antigen and constructed a high-quality phage display library. Seventeen nanobodies with different complementarity determining region (CDR) 3 sequences have been screened after 3 rounds of biopanning by phage display technology. The animal procedures were approved by the Institutional Animal Care and Use Committee (IACUC) of Fudan University School of Pharmacy. After purification, 7 nanobodies showed high cell binding activity by fluorescent activated cell sorting (FACS) identification. Furthermore, 3 nanobodies presented high endocytosis activity based on FACS and laser confocal microscopy, which also showed high affinity to EpCAM measured by ForteBio. According to this study, we aimed to provide a novel alternative approach to the EpCAM-targeted therapy and to provide guidance for the study of nanobody based immunotoxins for other targets.

BACKGROUNDThe molecular genetic research showed the association between X-linked hearing loss and mutations in POU3F4. This research aimed to identify a POU3F4 mutation in a nonsyndromic X-linked recessive hearing loss family.

METHODSA series of clinical evaluations including medical history, otologic examinations, family history, audiologic testing, and a high-resolution computed tomography scan were performed for each patient. Bidirectional sequencing was carried out for all polymerase chain reaction products of the samples. Moreover, 834 controls with normal hearing were also tested.

RESULTSThe pedigree showed X-linkage recessive inheritance pattern, and pathogenic mutation (c.499C>T) was identified in the proband and his family member, which led to a premature termination prior to the entire POU domains. This mutation co-segregated with hearing loss in this family. No mutation of POU3F4 gene was found in 834 controls.

CONCLUSIONSA nonsense mutation is identified in a family displaying the pedigree consistent with X-linked recessive pattern in POU3F4 gene. In addition, we may provide molecular diagnosis and genetic counseling for this family.

Asian Continental Ancestry Group ; Child ; Deafness ; genetics ; Female ; Genetic Predisposition to Disease ; Hearing Loss ; genetics ; Humans ; Male ; Mutation ; genetics ; POU Domain Factors ; genetics ; Pedigree