Introduction: Occult infections (OBIs) caused by hepatitis B virus (HBV) are detected by the presence of HBV DNA without surface antigens. The prevalence of HBsAg in general population of Pakistan is around 3%, but there is no data regarding the occurrence of OBIs. Aims & Objectives: The goal of this research was to assess the frequency of occult hepatitis B infection in pregnant females presenting to antenatal care unit of Shaikh Zayed Hospital, Lahore. Place and duration of study: These samples were handled at the Microbiology Department of Shaikh Zayed Hospital, Lahore. The duration of study was one year after the approval of synopsis. Material & Methods: Four hundred and sixty three pregnant women were included in this research. Serum was separated from their blood samples. HBsAg, Anti-HBcand Anti-HBs tests were performed using the ELISA technique on all the samples. Real time PCR was performed to find HBV DNA. Results: The frequency of occult hepatitis B was < 0.25 in this research. Among the 463 women tested during pregnancy, hepatitis B surface antigen was positive in 2 (0.4%) women. These two were excluded from the study. Out of 461 samples, hepatitis B surface antibody was positive in 61 (13.2%) samples and they were negative for hepatitis B core antibody. These 61 samples were also omitted from the research. 25 (5%) samples were positive for both Anti-HBc and Anti-HBs. 11 samples (2%) were Anti-HBc positive and Anti-HBs negative. In 364 (79%) samples, both Anti-HBs and Anti-HBc were absent. Polymerase Chain Reaction was performed on 400 samples. Conclusion: The frequency of occult hepatitis B is very low < 0.25% in pregnant women. It is not recommended to routinely screen pregnant women for hepatitis B virus DNA.

Background: p21SNFT (21 kDa small nuclear factor isolated from T cells) gene is known to be increasingly expressed in the cells of Hodgkin disease and Hodgkin cell lines. It was not investigated before if this gene had any effect on polyclonal T lymphocytes. For this purpose, we transduced this gene into polyclonal T lymphocytes and transplanted into mice. Materials and Methods: We used γ-retroviral vector to transduce this gene into polyclonal T lymphocytes, isolated from wild type black-6 mice. After confirmation of p21SNFT expression via marker gene eGFP (enhanced green fluorescent protein) and Western blot analysis, these cells were transplaned into immunocompromised Rag 1 deficient mice. The control group of mice was transplanted with γ-retroviral vector, carrying only marker gene (eGFP). The mice were followed up. The results showed that all 7 mice transplanted with p21SNFT-carrying polyclonal T lymphocytes developed massively enlarged mesenteric lymph nodes after 435 to 550 days of transplantation. Results: Histopathological analyses of these lymph nodes revealed the lymphoma, which resembled human peripheral T cell lymphoma type. Furthermore, immunophenotyping of tumor cells by FACS analysis revealed loss of T cell markers and expression of CD19 marker. From the control group, all five mice remained healthy and did not develop any tumor. Conclusion: The study concludes that γ-retroviral mediated transfer of p21SNFT transforms polyclonal T lymphocytes into malignant cells.