Existing variations on the gene structure of hepatitis E virus strains from some regions of China

Hepatitis E virus in Nepal: similarities with the Burmese and Indian variants

Hepatitis E has been the predominant type of acute hepatitis in Nepal both in adults and children, in sporadic and epidemic forms. We examined six hepatitis E virus (HEV) isolates obtained during an 8-year period, from 1987 to 1995, in the Kathmandu valley of Nepal. Analysis of portions of the putative helicase, polymerase and capsid genes demonstrated close genetic relatedness among themselves (> 96.4% identity) and with the Burmese (> 95.5%) and Indian (> 95.3%) isolates, and less so with the African (> 94.4%) and the Chinese (> 91%) isolates within the Asian genotype. Phylogenetic analysis placed the Nepali isolates in the Burma-India evolutionary branch and showed that the oldest isolate, TK78/87 was more similar to the Burmese isolates whereas the most recent isolates were closer to the Indian ones. Assuming no frameshifts, the Nepali isolates showed high amino acid conservation, but also unique changes when compared to other HEV isolates. Amino acid residue 614 of the capsid protein was identified as a possible marker to distinguish the Burma-Nepal-India from the China-Central Asian Republics subgenotype, and the Mexico genotype.

Hepatitis E virus (87A strain) propagated in A549 cells

A strain of hepatitis E virus (HEV), the 87A strain isolated in 2BS cells from the feces of a patient with hepatitis E, has been reported previously. In this study, the 87A strain was propagated in A549 cells, and the marked cytopathic effect (CPE) appeared in the infected monolayer cells. The size of this virus is about 30 nm in diameter. Furthermore, HEV-RNA from the supernatants of the virus of different passages was detected by polymerase chain reaction (PCR) amplification using ET1.1 HEV primers. A band of HEV for 239 bp from PCR products was revealed by electrophoresis. PCR products of the fourth passage were sequenced. These results show that the 87A virus replicates in the A549 cell line.