Provided is a method for large-scale production of lentivirus by using GMP-level serum-free suspension cells. Said method comprises the following steps: (a) providing a seed solution of packaged cells; (b) inoculating the seed solution in a first culture solution; (c) carrying out subculture of the packaged cells; (d) starting a liquid change operation when a liquid change trigger condition is met; (e) repeating steps (c) and (d) 1, 2 or 3 times; (f) starting a transfection operation when a transfection trigger condition is met; (g) optionally performing liquid change after transfection; (h) cultivating the transfected packaged cells; (i) starting harvesting and liquid change operations when a liquid change trigger condition is met; (j) repeating steps (h) and (i) 1, 2 or 3 times; (k) combining each of the recovered liquids; and (1) performing a purifying treatment. The culture solution used in each step is a serum-free cell culture solution.

Cell-stored barcoded viral protein deep mutational scanning libraries are described. The libraries can be used to map resistance mutations to therapeutic treatments. The libraries can be used to predict viruses that become resistant to therapeutic compounds and/or may more easily evolve to infect new species. The libraries can also be used to more safely study dangerous viruses that normally require high safety biocontainment facilities. The libraries include features that allow efficient collection and assessment of informative data, obviating many bottlenecks of previous approaches.

Provided herein are lipid particles containing a lipid bilayer enclosing a lumen or cavity, a henipavirus F protein molecule or biologically active portion thereof, and a targeted envelope protein containing a henipavirus envelope attachment glycoprotein G (G protein) or biologically active portion thereof and a binding domain, such as a single domain antibody (sdAb) variable domain. Also provided herein are targeted envelope proteins containing a G protein fused or linked to a binding domain, such as a sdAb variable domain, and polynucleotides encoding such proteins. Also provided are producer cells and compositions containing such targeted lipid particles and methods of making and using the targeted lipid particles.

Provided herein are protein-based purification matrices and methods of use thereof to purify biologics and/or to remove contaminants from a composition. Methods of bringing two or more biologics in close proximity are also provided. The disclosed compositions and methods allow for faster, more efficient purification of a biologic compared to traditional affinity chromatography.

We have found a way to make possible large-scale plasmid transfection using PEI to produce high titer viral vectors in fixed bed or adherent cell culture bioreactors by using PEI as a transfection agent, while avoiding formation of the PEI-plasmid precipitate which in prior art approaches clogged adherent bioreactor substrates. We have also found a way to improve PEI-based transfection by modifying how pH and CO.sub.2 are managed during transfection.

Described herein are Bovine immunodeficiency virus gag protein (“Bgag”) recombinant virus like particles (“VLPs”) comprising one or more different types of target pathogen proteins. Also described, are compositions comprising the novel Bgag VLPs and the methods of making and using the novel Bgag VLPs.

In accordance with the present invention, a method for increasing the yield of rLV vector particles comprising a trans gene encoding a therapeutic protein or fragment thereof is disclosed. In one approach, cells are transfected with plasmids encoding the necessary components for rLV production using a calcium chloride transfection mix at pH 7.1 wherein the calcium chloride and plasmids form a complex which is added to the cells at a constant speed. The cells are then incubated for a suitable time period wherein virus particle media is collected at least twice during the incubation period and stored in a cold storage unit, thereby reducing virus inactivation.

Disclosed are compositions for transfecting a nucleic acid molecule into a cell and their applications. Specifically, this relates to a composition suitable for transfecting a nucleic acid molecule into a cell, preferably a eukaryotic cell, including (i) at least one compound of general formula (II) or a tautomer, mesomer, racemate, enantiomer, diastereomer, or mixture thereof, or an acceptable salt thereof, and (ii) an acceptable excipient, buffering agent, cell culture medium, or transfection medium, wherein Y.sup.1, Y.sup.2, Y.sup.3, Z.sup.1, Z.sup.2, Z.sup.3, Z.sup.4, Z.sup.5, Z.sup.6, Z.sup.7, X.sub.1, X.sub.2, R.sub.3, P.sup.+, R, T, U and V are as defined in the description. Also disclosed are uses of the composition and to a method for in vitro or ex vivo transfection of live cells.

Disclosed are compositions for transfecting a nucleic acid molecule into a cell and their applications. Specifically, this relates to a composition suitable for transfecting a nucleic acid molecule into a cell, preferably a eukaryotic cell, including (i) at least one compound of general formula (I), preferably of general formula (III), or a tautomer, mesomer, racemate, enantiomer, diastereomer, or mixture thereof, or an acceptable salt thereof, and (ii) an acceptable excipient, buffering agent, cell culture medium, or transfection medium, wherein Y.sup.1, Y.sup.2, Y.sup.3, Z.sup.1, Z.sup.2, Z.sup.3, X.sub.1, X.sub.2, R.sub.3, P.sup.+, R and V are as defined in the description. Also disclosed are uses of the composition and to a method for in vitro or ex vivo transfection of live cells.

This invention relates to retroviral gene transfer vectors, particularly lentiviral vectors, pseudotyped with hemagglutinin-neuraminidase (HN) and fusion (F) proteins from a respiratory paramyxovirus, comprising a promoter and a transgene; and methods of making the same. The present invention also relates to the use of said vectors in gene therapy, particularly for the treatment of respiratory tract diseases such as Cystic Fibrosis (CF).