Expression Vectors:

Safe, stable and effective gene delivery

The human (HIV) and feline (FIV) Lentiviral Vector Systems provide exceptional tools to express any sequence in virtually all mammalian cells. The system consists of three main components:
(1) the lentiviral expression plasmids (also known as "transfer vector")
(2) the lentiviral packaging plasmid mix
(3) a producer cell line for packaging

Lentivector formats available

Stably Overexpress cDNAs
Choose from single or double promoter formats with CMV, EF1, PGK, UbC or MSCV promoter options and fluorescent protein or antibiotic markers.
Permanent Gene Knockdown with shRNA Overexpression
Choose from single or double promoter formats with H1 or U6 promoter options and fluorescent protein or antibiotic markers.
Overexpress microRNAs
Choose from single or double promoter formats and fluorescent protein or antibiotic markers.

Promoter options allow the choice of expression levels

Lentivirus Positive Transduction Controls

To create functional pseudoviral particles, the lentivector containing the expression construct is co-transfected with the packaging plasmids into the producer cell line. The packaging cells replicate the expression construct and package it into pseudoviral particles. These pseudoviral particles are then purified and used to deliver the expression construct to the cells of interest. Once delivered, the viral expression construct integrates, and the construct is expressed. Our lentivectors are self-inactivating. Upon integration into the genome, the 5’ LTR promoter is inactivated, which prevents formation of replication-competent viral particles. Thus, the transduced cell cannot produce additional viral particles since the cell does not contain the genes needed to produce the viral capsid, nor is there a functional 5’LTR to enable it to replicate the viral sequence.

In addition to yielding very high expression levels, the lentiviral system is very effective at delivering genetic material to almost any mammalian cell—including non-dividing cells and whole model organisms. Effective transduction with lentiviral pseudovirus particles does not require cells to be active or growing. The efficiency of lentiviral transduction is close to 100% so this system is ideal as an expression library vector.