Israel Medical Association Journal

Background: The humanized SCID mouse model is an attractive tool for testing gene therapy to combat human immunodeficiency virus infection in vivo.

Objectives: To devise a more specific gene therapy directed against HIV, replacing the formerly used interferon with either soluble CD4 molecule immunoadhesin (sCD4-IgG) and/or anti-gp41 monoclonal antibody (2F5), or negative transdominants (Tat, Rev).

Methods: Human monocytoid cell line (U937) was transfected with IFNa[1], b or g genes. 3T3 murine fibroblastic cell line was transfected with sCD4-IgG or 2F5, or both genes, and a human T4 cell line (CEM) was grafted to SCID mice. Negative transdominant genes (Tat, Rev or both) were also transduced in CEM T cell line. Animals were then challenged with HIV-1[2]. Viral load was followed.

Results: IFNa or b were potent anti-HIV, reducing viral load in vivo and inhibiting reverse transcriptase activity in human-removed cells from animals. sCD4-IgG immunoadhesin and gp41 monoclonal antibody resulted in a dramatic reduction of HIV-1 cellular and plasmatic viral load in humanized SCID mice. The simultaneous introduction of negative Tat and Rev genes resulted in a synergistic inhibition of HIV-1 replication in vivo.

Conclusions: Despite the marked reduction of HIV-1 propagation by IFN genes or by negative Tat and Rev transdominants, the gene therapy using soluble CD4 immunoadhesin or anti-gp41 was a more efficient preventive treatment against HIV infection.

Objective: To describe the clinical and epidemiological features of hepatitis B virus infection in Israeli children, and to evaluate their response and compliance to therapy.

Methods: We retrospectively studied 51 patients (34 males, 17 females), aged 2–18 years, from several medical centers in Israel.

Results: Of the 51 patients, 38 with elevated transaminase, positive hepatitis B e antigen and/or HBV DNA, and histologic evidence of liver inflammation were treated. Interferon was administered by subcutaneous injections three times a week for 3-12 months (dosage range 3–6 MU/m²). Only 16% were native Israelis, while 78% of the children were of USSR origin. A family history of HBV infection was recorded in 25 of the 51 patients (9 mothers, 16 fathers or siblings). Five children had a history of blood transfusion. The histological findings were normal in 3 patients, 24 had chronic persistent hepatitis, 14 had chronic active hepatitis and 2 had chronic lobular hepatitis. Five children also had anti-hepatitis D virus antibodies. Twelve of the 38 treated patients (31.5%) responded to IFN completely, with normalization of the transaminase levels and disappearance of HBeAg and HBV DNA. In no patient was there a loss of hepatitis B surface antigen. The main side effects of IFN were fever in 20 children, weakness in 10, headaches in 9, and anorexia in 6; nausea, abdominal pain, and leukopenia were present in 3 cases each. The response rate was not affected by age, country of origin, alanine/aspartate aminotransferase levels, or histological findings. However, a history of blood transfusion was a predictor of good response, 60% vs 27% (P<0.05).

Conclusions: We found IFN to be a safe and adequate mode of treatment in children with chronic HBV infection, regardless of their liver histology and transaminase levels. Therefore, in view of the transient side effects associated with this drug, we recommend considering its use in all children with chronic hepatitis B. 

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HBV = hepatitis B virus

IFN = interferon

HBeAg = hepatitis B e antigen