Methods of administering adenoviral vectors

Details Methods of administering adenoviral vectors Methods of administering adenoviral vectors

2001-04-16

2003-07-22

Shukla, Ram R. (Department: 1632)

Drug, bio-affecting and body treating compositions

Whole live micro-organism, cell, or virus containing

Genetically modified micro-organism, cell, or virus

C514S04400A, C435S320100, C435S325000, C424S069000, C424S093100, C424S199100, C424S233100

Reexamination Certificate

active

06596270

ABSTRACT:

TECHNICAL FIELD OF THE INVENTION
The present invention relates to methods for administering gene products to animals using adenoviral vectors.
BACKGROUND OF THE INVENTION
Modified viruses have proven convenient vector systems for investigative and therapeutic gene transfer applications, and adenoviral vector systems present several advantages for such uses. Adenoviruses are generally associated with benign pathologies in humans, and the 36 kb of the adenoviral genome has been extensively studied. Adenoviral vectors can be produced in high titers (e.g., about 10
13
pfu), and such vectors can transfer genetic material to nonreplicating, as well as replicating, cells; in contrast with, e.g., retroviral vectors, which only transfer genetic material to replicating cells. The adenoviral genome can be manipulated to carry a large amount of exogenous DNA (up to about 8 kb), and the adenoviral capsid can potentiate the transfer of even longer sequences (Curiel et al.,
Hum. Gene Ther.
3: 147-154 (1992)). Additionally, adenoviruses generally do not integrate into the host cell chromosome, but rather are maintained as a linear episome, thus minimizing the likelihood that a recombinant adenovirus will interfere with normal cell function. Aside from being a superior vehicle for transferring genetic material to a wide variety of cell types, adenoviral vectors represent a safe choice for gene transfer, a particular concern for therapeutic applications.
A variety of recombinant adenoviral vectors have been described. Most of the vectors in use today derive from the adenovirus serotype 5 (Ad5), a member of subgroup C. An exogenous gene of interest typically is inserted into the early region 1 (E1) of the adenovirus. Disruption of the E1 region decreases the amount of viral proteins produced by both of the early regions (DNA binding protein) and late regions (penton, hexon, and fiber proteins), preventing viral propagation. Replication-deficient adenoviral vectors require growth in either a complementary cell line or in the presence of an intact helper virus, which provides, in trans, the essential E1 functions (Berker et al.,
J. Virol.
61: 1213-1220 (1987); Davidson et al.,
J. Virol.
61: 1226-1239 (1987); Mansour et al.,
Mol. Cell Biol.
6: 2684-2694 (1986)). More recently, adenoviral vectors deficient in both E1 and the early region 4 (E4) have been used to substantially abolish expression of viral proteins. In order to insert the larger genes (up to 8 kb) into the adenoviral genome, adenoviral vectors additionally deficient in the nonessential early region 3 (E3) and the early region 2 (E2) can be used. Multiply deficient adenoviral vectors are described in published PCT patent application WO 95/34671.
One limitation of adenoviral vector systems is the ability of the adenoviral vector to transduce a wide variety of proliferating and quiescent cells (Michou et al.,
Gene Ther.
4: 473-482 (1997)). This ability, while a benefit in transducing the target area, is a limitation when the adenoviral vector “leaks” out of the targeted area and transduces other cells it contacts. Tranduction of the surrounding cells is a serious problem when the gene product encoded by the adenoviral vector is harmful, toxic, or otherwise undesirable with respect to these non-targeted areas.
Another limitation of the adenoviral vector system is the cellular and humoral immune response generated within the host animal. Initial administration elicits a reaction from both CD8
+
and CD4
+
T lymphocytes, which eliminate virus infected cells within 28 days after infection, limiting the duration of the transgene expression. In addition, neutralizing antibodies produced by B lymphocytes in cooperation with CD4
+
cells inhibit the effectiveness of repeat administration of the adenoviral vector. Proliferation and specificity of the antibodies to the adenoviral vectors occurs through interactions among the adenoviral vector, B-cell surface immunoglobulins and activated CD4
+
surface proteins (particularly CD40 ligand (CD40L), which binds CD40 on the surface of B cells) (Yang et al.,
J. Virol.
69: 2004 (1995)).
Attempts to circumvent the humoral immune response to allow repeat administration of the adenoviral vector have met with limited success. These attempts have focused in two areas: immunosuppression and alteration of the adenoviral vector. Several groups have experimented with various immunosuppressant drugs or antibodies specific for CD4
+
, CD40L, or CTLA4Ig to reduce the adenovirus-specific humoral immune response (Lee et al.,
Hum. Gene Ther.
7: 2273 (1996) (CD4
+
); Yang et al.,
J. Virol.
70: 6370 (1996) (CD40L); Kay et al.,
Nature Gen.
11: 191 (1995) (CTLA4Ig)). Although some of these results have been encouraging, there is a substantial risk associated with systemic immune suppression in a clinical setting. Alteration of the adenoviral vector is time consuming and has not been entirely successful in sufficiently attenuating the immune response. Limited readministration of the adenoviral vector has been accomplished when adenoviral vectors of different serotypes within the same subgroup are used; however, persistence of expression of the transgene was not comparable to the initial administration (Mack et al.,
Hum. Gene Ther.
8: 99-109 (1997)).
Accordingly, there is a need for improved methods of administering adenoviral vectors to animals, particularly, to prevent leakage of the adenoviral vector from the target area and to circumvent the humoral immune response elicited by adenoviral vectors. The present invention provides such methods. This and other advantages of the present invention, as well as additional inventive features, will be apparent from the description of the invention provided herein.
BRIEF SUMMARY OF THE INVENTION
The present invention provides a method of targeting a gene product to a particular muscle of an animal. The method comprises inducing in an animal systemic neutralizing antibodies to an adenoviral gene transfer vector and administering the adenoviral gene transfer vector comprising an exogenous gene encoding a gene product to a particular muscle of the animal. Administration is such that the exogenous gene is expressed and the gene product is produced in the particular muscle of the animal and the adenoviral gene transfer vector is neutralized outside of the particular muscle of the animal by the systemic neutralizing antibodies.
The present invention further provides a method of producing a gene product in a skeletal muscle of an animal. The method comprises initially administering an adenoviral vector to a skeletal muscle of an animal, and, at least seven days after administration, subsequently administering an adenoviral gene transfer vector comprising an exogenous gene encoding a gene product to the skeletal muscle of the animal. Administration is such that the exogenous gene is expressed and the gene product is produced in the skeletal muscle of the animal.
The invention may best be understood with reference to the following detailed description.
DETAILED DESCRIPTION OF THE INVENTION
The present invention provides methods useful in the administration of gene products to animals using adenoviral gene transfer vectors. The ability to target an adenoviral vector and to administer repeatedly a therapeutic adenoviral vector in a clinical setting is useful in improving treatment efficacy and in enabling the treatment of diseases. This invention provides a method to limit the infection of non-target tissue following administration of an adenoviral vector to a particular muscle of an animal. The vector targeting potential is useful for cardiac, particularly, endocardial, administration, as the risk of misinjection of the adenoviral vector is high. As adenoviral vectors cannot be readministered systemically, the present invention also provides a method for repeat administration of an adenoviral gene transfer vector comprising an exogenous gene to the skeletal muscle of an animal.
The term “exogenous gene,” as it is used herein, refers to any

Affiliated with

Also associated with

Rating

Methods of administering adenoviral vectors does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Methods of administering adenoviral vectors, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Methods of administering adenoviral vectors will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3042704