Advance in Reseach on Human Immunodeficiency Virus Type I Vector

Human immunodeficiency virus type-I (HIV-I), one kind of lentiviruses, was characterized by a complex genome that encodes two regulatory proteins and four accessory proteins in addition to the common gag, pol and env gene products. So far, a few of different types of replication-defective vectors were constructed, the highest viral titer from one of which was above 10(7) TU/ml. Several studies on packaging cell line found that eliminating the four accessory genes would have few effect on transduction ability of vector and split-genome package system could reduce the possibility of producing replication-competent virus. There are two kinds of characters on HIV-I vectors. Firstly, it was highly efficient in transducing CD34(+) human hematopoietic stem/progenitor cells; secondly, repeated injections of the HIV-I vector into animal did not elicit the rejection response. HIV-I vector had an extensive host range.