Antibody testing and RT-PCR results in hepatitis C virus (HCV) infection: HCV-RNA detection in PBMC of plasma viremia-negative HCV-seropositive persons.

To evaluate the concordance between viremia and antibody testing in hepatitis C virus (HCV) diagnosis, 682 serum or plasma samples collected from patients with known or suspected HCV infection were tested. An overall concordance of 77% between serological and PCR results was found, 5% was RNA positive/antibody negative and 18% antibody positive/RNA negative. The relationship between HCV infection, risk group and clinical diagnosis was studied in 116 patients: the presence of anti-HCV antibody without viremia was shown in 72.7% of asymptomatic subjects and 17.6% of chronic hepatitis subjects without interferon treatment. However, the detection of HCV-RNA in peripheral blood mononuclear cells (PBMC) in four out of 38 plasma viremia-negative HCV-seropositive subjects (10.5%), showed that HCV-RNA could persist in PBMC and could begin the viral replication again at different times. The detection of HCV-RNA in PBMC in anti-HCV-positive subjects without viremia could reduce false-negative results of HCV-RNA testing by RT-PCR in serum or plasma.

Construction and characterization of retroviral vectors for interleukin-2 gene therapy.

Several investigators have employed interleukin-2 (IL-2) gene transfer to enhance the immunogenicity of tumor cell vaccines. We describe in this report the construction and characterization of retroviral vectors for IL-2 gene therapy. Human IL-2 cDNA with a chimeric rat preproinsulin/IL-2 DNA leader sequence was subcloned into the pLXSN (long terminal repeat promoter) and pLNCX (cytomegalovirus [CMV] promoter) vectors to generate the plasmids pLXSN-iIL2 and pLNCX-iIL2, respectively. Human IL-2 cDNA with a chimeric human tissue factor/IL-2 DNA leader sequence was utilized to construct the vector pLXSN-tIL2. The levels of IL-2 secreted by transduced tumor cells and fibroblasts were evaluated by enzyme-linked immunosorbent assay (ELISA) of culture supernatants and compared with those of normal peripheral blood mononuclear cells (PBMC) activated in vitro with calcium ionophore and phorbol 12-myristate 13-acetate. The highest levels of IL-2 secreted by transduced tumor cells (760 units/10(6) cells/24 h), adult fibroblasts (625 units/10(6) cells/24 h), and embryonic fibroblasts (3,975 units/10(6) cells/24 h) were 150- to 1,000-fold higher than than secreted by the activated PBMC (4 units/10(6) cells/24 h). Similar levels of IL-2 were expressed by human fibroblasts transduced with pLXSN vectors employing the preproinsulin (pLXSN-iIL2) or tissue factor (pLXSN-tIL2) leader sequences (range in IL-2 units/10(6) cells/24 h pLXSN-iIL2 = 375-625 vs. pLXSN-tIL2 = 90-440). Because IL-2-transduced cells for clinical applications are generally irradiated to prevent cellular proliferation, we evaluated the effects of radiation on IL-2 production. Radiation doses between 1,500 and 10,000 cGy resulted in gradual decreases in IL-2 secretion by transduced cells. The range of the decrease in IL-2 secretion was 7-11% by day 7, 0-29% by day 14, and 25-50% by day 35. For clinical applications, stable production of the vector in high concentrations is an important consideration. The retroviral vector pLXSN-tIL2 produced the highest viral titer and was chosen for further characterization. Southern blot analysis of SacI-digested genomic DNA from the LXSN-tIL2 producer cell line and SacI-digested pLXSN-tIL2 plasmid DNA revealed the expected 3.2-kbp fragment, suggesting the absence of transgene rearrangement and the suitability of this vector as a candidate for clinical applications.

The potential role of hepatitis C virus in the pathogenesis of the neurological syndrome in chronic hepatitis C.

A 72-year-old man developed chronic sensory neuropathy (CSN) during chronic hepatitis C (HCV) infection. Neurological symptoms began one year after acute HCV hepatitis and slowly worsened over three years. No conventional cause for CSN was found. Circulating antinervous tissue antibodies (including anti-Hu) and inflammatory infiltrates in sural nerve biopsy specimens were absent. However, the presence of anti-HCV antibody and HCV-RNA in cerebrospinal fluid indicated that HCV had reached the intrathecal compartment, suggesting the direct viral involvement in the pathogenesis of CSN.

[Epidemiologico-clinical considerations on a case file of acute hepatitis observed 1980-1983]. / Considerazioni epidemiologico-cliniche su una casistica di epatite acuta osservata negli anni 1980-1983.

Between January 1980 and December 1983, 332 consecutive cases of acute hepatitis were observed in adult patients admitted to the Department of Infectious Disease and Gastroenterology of Siena. Sex and age of the patients, the presence of jaundice, the maximum value of the serum-glutamate-pyruvate-transaminase (SGPT) were considered. Serum specimens were tested for hepatitis B surface antigen (HBsAg), antibody against hepatitis B core antigen (anti-HBc) of the IgM class, antibody against hepatitis A virus (anti-HAV) of the IgM class, antibody against cytomegalovirus (CMV) of the IgM class, Paul Bunnel Davidshon reaction. Hepatitis A was diagnosed in 25 cases (7.5%). Hepatitis B in 167 (50.3%). Hepatitis due to CMV in 2 cases (0.6%). And, by exclusion, hepatitis non A, non B in 138 cases (41.6%). Male patients were affected with significantly higher frequency than female (p less than 0.01); the same was seen for young patients (14-30 years) compared to the older ones (31-50 years, and over 50 years) (p less than 0.01 in both). Biochemical investigation showed that hepatitis A and B had a significantly higher, maximum SGPT value than hepatitis non A non B (p less than 0.01 in both). Icteric patients were significantly more frequently observed among hepatitis A and B cases than hepatitis non A non B cases (p less than 0.01 in both).

[Epidemiological study on the incidence of viral hepatitis in the Province of Siena]. / Indagini epidemiologiche sulla incidenza della virus-epatite in provincia di Siena

The AA. carried out an epidemiological survey on 1,420 cases with viral hepatitis ascertained in the Province of Siena during the period January 1, 1962-December 31,1972. Age, sex, profession, place of origin, annual and seasonal prevalence, therapeutic measures, geographic and social-economic features of several districts, and other characteristics of the affected people were examined. The results obtained were discussed keeping in mind the various parameters examined.