Direct protein delivery with engineered microvesicles

1. An isolated microvesicle as released from eukaryotic cells, obtained by the steps comprising:

culturing eukaryotic cells in a medium, wherein said eukaryotic cells release microvesicles by secreting said microvesicles into the medium

collecting said medium to provide a cell supernatant comprising said secreted microvesicles;

filtering the collected cell supernatant comprising said microvesicles to provide a filtrate containing microvesicles;

centrifuging the filtrate to concentrate the microvesicles in the filtrate; and

isolating the microvesicles;

wherein said eukaryotic cells comprise a nucleic acid encoding a viral membrane fusion protein and a protein of interest, wherein said protein of interest is not covalently bonded to said viral membrane fusion protein, and wherein said microvesicle comprises said viral membrane fusion protein and said protein of interest and does not contain any viral structural protein.

2. The isolated microvesicle of claim 1 , wherein said microvesicle does not contain any nucleic acid encoding for the protein of interest.

3. The isolated microvesicle of claim 1 , wherein said microvesicle is a vesicle having a size between 40 and 150 nm.

4. The isolated microvesicle of claim 1 , wherein said microvesicle is a vesicle having a density between 1.08 g/ml and 1.11 g/ml.

5. The isolated microvesicle of claim 1 , wherein said viral membrane fusion protein is selected from the group consisting of Class I viral membrane fusion proteins and Class III viral membrane fusion proteins.

6. The isolated microvesicle of claim 1 , wherein said viral membrane fusion protein is selected from the group consisting of rhabdovirus G, herpesvirus gB, EBV gB, thogotovirus G, baculovirus gp64, and Borna disease virus glycoprotein.

7. The isolated microvesicle of claim 1 , wherein said viral membrane fusion protein is VSV-G or baculovirus gp64.

8. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group consisting of membrane receptors, apoptotic factors, viral proteins, and nuclear proteins.

9. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group of nuclear proteins consisting of: transcription factors or cofactors, the tTA tetracycline transactivator, VP16 and VP16-containing fusion proteins, the CRE recombinase, Cre-Ert2 recombinase, FLP recombinase or flippase, Hin recombinase, RecA/RAD51, Tre recombinase, meganucleases, transcription factors, Retinoic acid Receptor, vitamine-B3 receptor, CCAAT/enhancer-binding proteins, Ikaros, Pax5, Janus Kinase, E2A, Bcl-6, EBF family, Egr 2 and 3, K1F5, TcF4, MyoD, SUM-1, myogenin, myf-5, MRF4, Pitx2, Egr 2 and Egr 3, NFkB, AP1, AP2, POU factors, Sp1/Sp3, bHLH, Engrailed 2, Foxg1, ELF3, Erm, Olf-1, Pax6, alpha-Pa1/Nrf-1, Nurr1 and Pitx3.

10. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group of viral proteins consisting of: tat, rev, gp120, GP41 from HIV-1/2, SIV, vpx from SIV, tax, rex from HTLV-1, EB1, EBNA2, EBNA1, BHRF1, NS3, NS5A, NS1, NS2, Core, E1, E2 from HCV, small T, large T antigen from SV40, NS1, Neuraminidase and HA from Influenza.

11. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group of apoptotic factors consisting of: BAX, BID, BAK, BAD, and FasL.

12. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group of fluorescent proteins consisting of: GFP, YPF, Venus, CFP, DsRed, Cherry-Red and DsRed 2.

13. The isolated microvesicle of claim 1 , wherein said protein of interest is selected from the group of membrane receptors consisting of: CD81, the ectopic receptor mCAT-1, CXCR4, CD4, CCR5, sialic acid-rich proteins, claudins, CD21, T-cell receptors, B cell receptors, CFTR and TNFR1.

14. The isolated microvesicle of claim 9 , wherein said transcription factor is selected from the group consisting of: GATA-1, FOG, NF-E2, TAL1/SCL, EKLF, FBI-1, RUNX1, and PU.1.

15. The isolated microvesicle of claim 9 , wherein said meganuclease is Sce1.

16. The isolated microvesicle of claim 1 , wherein the centrifuging step is performed by ultracentrifugation.