Lentiviral particle

Figure 2 Generation of retroviral and lentiviral particies. Packaging ceiis are transfected with a chemokine receptor-containing plasmid (pCKR) in advance (A) or simultaneously (B) with the vectors needed to generate retroviral (pCGP) or lentiviral particles (psPAX2). During budding, viral particles incorporate the cell membrane as a coating that retains the structure and functional properties of the receptor.

Vega, B., Munoz, L. M., Holgado, B. L., Lucas, P., Rodriguez-Frade, J. M., Calle, A., et al. (2011). Technical advance Surface plasmon resonance-based analysis ofCXCL12 binding using immobilized lentiviral particles. Journal of Leukocyte Biology, 90, 399-408. 

Scherr, M., Battmer, K., Blomer, U., Ganser, A., Grez, M. (2001). Quantitative determination of lentiviral vector particle numbers by real-time PCR. BioTechniques, 31, 520-524. 

The envelope glycoproteins of wild-type retroviruses and lentiviruses bind to cell surface receptors to facilitate entry of the vims into the cytoplasm where the viral RNA is reverse transcribed to form a cDNA, the proviras. This provirus is translocated to the nucleus where it integrates into the host cell chromosomes and through the normal process of DNA transcription encodes new viral proteins and new viral RNA, which are assembled at the cell surface into new viral particles. Replication-defective retroviral and lentiviral vectors infect cells by similar mechanisms, but unlike wild-type viruses, the integrated provirus from these vectors encodes the therapeutic gene and viral particles are not produced. 

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