Objective:To find a short, neutralizing antibody-inducible, ORF2-encoded protein by means of comparing the immunogenicity of pN472-C617 and pN477-C613 which represent amino acids 472-617 and 477-613 of HEV ORF2-encoded protein of hepatitis E virus(HEV) genotype 4, respectively.Methods:The two recombinant proteins were expressed, purified, and then used to immunize BALB/c mice. Anti-HEV titers in the immune sera were detected by ELISA. Anti-HEV neutralizing activity was tested by a PCR-based in vitro neutralization assay.Results:Both of the two recombinant proteins were efficiently expressed in E.coli in soluble forms. The purified proteins induced mice to develop high levels of anti-HEV specific antibodies. However, only the immune sera obtained from the mice immunized with pN472-C617 showed the neutralizing activity to the homologous HEV strain by preventing the virus from absorption on PLC/PRF/5 cells surfaces and replication in the cells. The immune sera against pN477-C613, which was truncated five amino acids from both N- and C-terminal of pN472-C617, had no HEV neutralizing activity.Conclusion:The pN472-C617 is the shortest neutralizing antibody-inducible ORF2-encoded protein of HEV reported in literatures so far. It may be considered as a potential candidate for a novel HEV subunit vaccine in our future study.

OBJECTIVETo analyze the mutations in a pedigree with maternally inherited sensorineural hearing loss, and to investigate whether 235delC heterozygote mutation in gap junction protein beta 2 (GJB2) gene modulates the severity of hearing loss associated with the A1555G mitochondrial mutation.

METHODSThe PCR products were digested with the Alw26 I restriction enzyme, followed by direct sequencing to detect the mitochondrial mutations in 72 members of a core pedigree of an extensive family with matrilineal nonsyndromic deafness; 235delC mutation of the GJB2 gene was screened in this family by using the Apa I restriction enzyme and direct sequencing.

RESULTSThe A1555G mutation of the mitochondrial DNA was present in all 27 members of maternal line, out of them, 21 members had phenotype of deafness (77.8%), with a high penetrance. Only three maternal line members of 72 members possessed 235delC heterozygote mutations, and the three had different phenotypes.

CONCLUSIONThe A1555G homozygous mutation of mitochondrial DNA is the susceptive etiological factor of nonsyndromic deafness in this family, but in the study of this pedigree, the 235delC heterozygous mutation in GJB2 gene may not aggravate the symptoms of hearing loss associated with the A1555G mitochondrial mutation.

Base Sequence ; Connexin 26 ; Connexins ; genetics ; DNA Mutational Analysis ; DNA, Mitochondrial ; chemistry ; genetics ; Female ; Hearing Loss, Sensorineural ; genetics ; Heterozygote ; Humans ; Male ; Mutation ; Pedigree ; Polymerase Chain Reaction

OBJECTIVETo study the status of CDKN2/p16 gene point mutation in lung cancer.

METHODSPolymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) and sequencing were used to detect the point mutation of CDKN2/p16 gene exon 2 in 89 cases of lung cancer.

RESULTSIn 69 cases of the lung cancer without deletion of CDKN2/p16 gene exon 2, 16 cases were found to have suspicious abnormality of CDKN2/p16 gene exon 2 by PCR-SSCP, and in these 16 cases, 9 were found to harbor point mutations of CDKN2/p16 gene exon 2 by automated sequencing analysis.

CONCLUSIONThe point mutation is one of the mechanisms for CDKN2/p16 gene inactivation, but it is not the chief mechanism. The inactivation of CDKN2/p16 gene aroused by point mutation plays a role to some extent in the genesis and progression of lung cancer.

Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; Exons ; Humans ; Lung Neoplasms ; genetics ; Point Mutation ; Polymerase Chain Reaction ; methods ; Polymorphism, Single-Stranded Conformational ; Sequence Analysis, DNA ; methods