Methods of producing microbubble drug conjugates, viral gene therapy microbubble conjugates and targeted microbubbles
View Patent ↗The present invention relates to methods of producing microbubble drug conjugates, viral gene therapy microbubble drug conjugates, and disease-targeting microbubbles, for clinical and preclinical ultrasound-mediated therapeutic and diagnostic applications. It includes methods to produce viral vector gene therapy microbubble drug conjugates with antibody linkers conjugated to lipid shelled microbubbles that both bind to and neutralize viral vectors such that the viral gene therapy can transduce and effect permanent genetic changes only after ultrasound is used to disassociate the viral gene therapy from microbubbles at diseased regions of the body.
1 . A method of producing lipid-shelled microbubble drug conjugates (MDCs) for viral gene therapy, comprising:
a) providing an antibody having binding specificity to a viral vector;
b) conjugating the antibody to one or more functionalized lipids to form antibody-lipid conjugates;
c) generating lipid-shelled microbubbles comprising the antibody-lipid conjugates on the microbubble shell surface; and
d) associating a viral gene therapy vector with the antibody on the microbubble shell to form viral gene therapy MDCs;
wherein the viral vector is selected from the group consisting of adeno-associated viral vectors, adenoviral vectors, lentiviral vectors, herpes simplex viral vectors, retroviral vectors, and oncolytic viral vectors;
and wherein the antibody binds the viral vector and associates the viral vector with the lipid-shelled microbubble.
2 . A method for optimizing association between a viral gene therapy vector and a viral gene therapy microbubble drug conjugate (MDC) produced according to the method of claim 1 , comprising:
a) providing a plurality of antibodies having different binding strengths to a viral vector;
b) producing a plurality of viral gene therapy MDCs using the antibodies;
c) exposing the MDCs to ultrasound under conditions sufficient to disrupt, oscillate, or otherwise activate the microbubbles;
d) determining release of the viral vector from the MDCs and transduction of target cells by the released viral vector; and
e) selecting an antibody having a binding strength that maintains association of the viral vector with the MDC during circulation and permits ultrasound-mediated release of the viral vector while maintaining viral transduction activity.
3 . The method of claim 2 , wherein the antibody comprises a viral vector-binding domain that binds a surface epitope of the viral vector and inhibits or reduces receptor-mediated cellular entry of the viral vector while the viral vector remains associated with the lipid-shelled microbubble during systemic circulation, thereby reducing off-target transduction prior to ultrasound-mediated release of the viral vector at a target treatment site.