Early stages of rabbit haemorrhagic disease virus infection monitored by polymerase chain reaction.

In order to define more accurately the initial events that take place during rabbit haemorrhagic disease virus (RHDV) infection, different organs of experimentally infected rabbits were analysed for the presence of the virus and correlated with histopathological observations. A total of 24 rabbits were intranasally inoculated with a viral suspension, and tissue samples were taken from the liver, spleen, kidney, lung, thymus, lymph node and tonsil at different intervals post-inoculation (2, 4, 6, 12, 18, 24, 30, 36, 48, 50, 51, 70 and 72 h). Histopathological observations revealed the presence of the first significant lesions at 30 h post-inoculation (p.

Detection of rabbit haemorrhagic disease virus isolates and sequence comparison of the N-terminus of the capsid protein gene by the polymerase chain reaction.

At present there is no sensitive method for the detection of rabbit haemorrhagic disease virus (RHDV), a calicivirus causing high mortality in rabbit populations. For this purpose a reverse transcriptase polymerase chain reaction (RT-PCR) was established in the N-terminal portion of the RHDV capsid region. The RT-PCR was 10(4)-fold more sensitive than ELISA testing for the detection of the virus and was able to detect as few as 12 copies of template cDNA.

Clinical relevance of the detection of hepatitis delta virus RNA in serum by RNA hybridization and polymerase chain reaction.

Hepatitis delta virus nucleic acid was detected by dot-blot hybridization using RNA probe and reverse transcription/polymerase chain reaction amplification in 223 serum samples from 66 patients with hepatitis D virus infection. Seven cases with chronic hepatitis D virus infection were treated with interferon: six for 3 months and one for 7.5 years.

Selective detection of human hepatitis B virus surface and core antigens in peripheral blood mononuclear cell subsets by flow cytometry.

The presence of hepatitis B surface protein (HBs) and hepatitis B core protein (HBc) was investigated, by flow cytometry, on the surface of peripheral mononuclear cells (PBMC) from cells of the following phenotype: CD3 (T lymphocytes), CD4 (T helper/ inducer), CD8 (T cytotoxic/suppressor), CD19 (B lymphocytes) and CD56 [natural killer (NK) cells] among eight patients suffering from chronic hepatitis B and five healthy HBV-negative subjects. This study demonstrated the presence of HBsAg and HBcAg on the lymphocyte surface for most of the patients. The mean percentage of labelled cells was 17% for HBsAg and 15% for HBcAg.

Monitoring of early events of experimental woodchuck hepatitis infection: studies of peripheral blood mononuclear cells by cytofluorometry and PCR.

The peripheral blood mononuclear cells (PBMC) of woodchucks experimentally infected by woodchuck hepatitis virus (WHV) were examined simultaneously for the presence of membrane associated WHV antigens by cytofluorometry, and for WHV DNA and RNA sequences by the polymerase chain reaction (PCR). Four woodchucks were inoculated: two with a well-defined infectious inoculum and two with an inoculum obtained from an animal at the late incubation phase, which was positive for WHV DNA by PCR but still devoid of WHV markers. Infection was demonstrated in all four inoculated woodchucks by the appearance at different times of WHV DNA and WHV antigens in both leucocytes and serum.