Establishment of the methodology for quantifying lentiviral vector transcriptional read-through rate / 生物工程学报

As an effective vehicle for bio-research and for gene therapy, Lentiviral Vector (LV) has been drawn large attention in recent years. However, transcriptional read-through limits its application. In order to understand the extend of LV read-through in chromosome, a reliable method to assess transcriptional read-through rate is needed. Here, we report the method as follows: 293T cells were transfected with the lentiviral transfer vectors which borne with two LTRs at its two ends in order to mimic the state of "proviral vectors" in chromosome. Using the primers specific for 3'U5 and 3'U3, read-through and total transcripts were reverse transcribed, respectively. These two cDNAs were quantified by realtime PCR using the primers and probe specific for 5'end of 3'U3. Read-through rate was then calculated by the division of the two. Meanwhile, read-through product of green fluorescence protein was also analyzed by Fluorescence Activated Cell Sorter. They both reciprocally proved the principal and confirmed that self-inactivated LV appeared higher read-through rate than the wild type one. The method described in this article, therefore, provides a useful technique to study how to reduce read-through rate, and improve the bio-safety of LV.

The Damage Mechanisms of Iron Ion in Intracerebral Hemorrhage and the Neuroprotective Effects of Iron Chelator / 国际脑血管病杂志

A series of pathophysiologic changes in brain tissues will occur after intracerebral hemorrhage, including the enlargement of hematoma, metabolism abnormality in perihematoma tissues, and formation of cerebral edema. Recent researches have demonstrated that iron ions play an important role in the secondary brain injury after intracerebral hemorrhage. Iron chelator can block iron-induced injury process by specifically binding iron ions. This article reviews the changes of iron metabolism, iron-related mechanisms of brain injury, and the neuroprotective effect of iron chelator.

Molecular identification of human/goat xenogeneic model / 中华血液学杂志

<p><b>OBJECTIVE</b>To identify the human hematopoietic stem cells from the human/goat xenogeneic model with molecular techniques.</p><p><b>METHODS</b>DNA and total RNA were extracted from 11 transplanted goat peripheral blood cells. Human CD(34), GPA and SRY genes were amplified with PCR in these samples, and CD(34), GPA mRNA transcripts were detected using RT-PCR in 5 and 6 goat peripheral blood cells, respectively. Southern blot analysis was performed in 8 goat DNAs to detect the human specific alpha-satellite sequence. Meanwhile FISH was also performed to detect the human cells in goat blood with a probe of human Y chromosome.</p><p><b>RESULTS</b>Human CD(34) and GPA genes could be detected with PCR in all the 11 goats, and SRY gene did in 5 goats transplanted with hematopoietic stem cells derived from male human babies. Southern blot showed that human specific alpha-satellite sequence was present in 8 goats. By RT-PCR, human CD(34) mRNA was detected in 5 experimental goats, GPA mRNA was found in the other 6 experimental goats and FISH assay showed that some peripheral blood cells of the human/goat xenogeneic model were positive.</p><p><b>CONCLUSION</b>Existence of human cells in the recipient goats was identified by molecular detection, which was feasible for the examination of human/goat xenogeneic models.</p>