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At least 1,531 records · Page 85Linked to original sources
PubMed2000

Purification of recombinant adeno-associated virus vectors by column chromatography and its performance in vivo.

Recombinant adeno-associated virus (AAV) holds much promise for human gene therapy. While evidence indicates that AAV mediates long-term gene transfer in several different tissues, difficulty in preparing and purifying this viral vector in large quantities remains a major obstacle for evaluating AAV vectors in clinical trials. The current method of purification, based on sedimentation through cesium chloride, is not scaleable and yields product of insufficient quality. In this article we report a new technique for purifying AAV, using a fully closed two-column chromatography system. Yields of AAV vectors purified by this method are high, potency is increased, and the purity of column-purified preparations is substantially improved. We previously reported a novel method to generate AAV based on an AAV Rep/Cap-containing cell line (B50) and an Ad-AAV hybrid virus, which is amenable to scale-up in bioreactors. By combining the new, fully scaleable purification process we report here with the B50/hybrid production method, it would be feasible to prepare AAV vectors to the scale and purity required for clinical and potential commercial applications.

Animals↗
PubMed2000

Gene transfer into the central nervous system using herpes simplex virus-1 vectors.

Manipulation of gene expression in developing or in mature central nervous systems (CNS) holds a promise for the resolution of many compelling neurobiological questions, including the feasibility of gene therapy to treat diseases of the brain. In this context, a number of viral vectors have been used in recent years to introduce and express genes into the CNS. This article discusses a gene transfer system based on the Herpes Simplex Virus-1 (HSV-1). We describe here the use of non-replicating, non-toxic HSV-1 vector, 8117/43, in a series of studies carried in our joint program. This vector proves further the utility of HSV-1 as a delivery vehicle to a number of distinct sites within the CNS.

Animals↗
PubMed2001

[Gene transfer--ways of administration, advantages, possible unsuitability and hazards].

BACKGROUND: Reports about successful gene therapy are now published after a period of more than ten years of trial and error. The key problem is to get DNA from genes or gene fragments into the target cells to be transcribed. MATERIAL AND METHODS: A brief review of transfer techniques is given, based upon the authors' own research and the literature in the field. RESULTS: In most cases, a vector (modified virus DNA or RNA, or plasmid DNA) is used as a vehicle. Retrovirus (RNA virus), adenovirus (DNA virus) and adeno-associated virus (DNA virus) are frequently used. Non-viral vectors such as plasmid DNA, liposome-linked DNA, protein DNA conjugates and artificial chromosomes are also relevant. Retrovirus has been used in about 60% of all gene therapy protocols. One problem is how to produce enough modified retrovirus for clinical use, hence retrovirus has mainly been used in ex vivo gene therapy, in which the number of target cells to be infected with the vector is limited and much lower than in in vivo therapy. INTERPRETATION: Increased insight into the genome has taught us that genes can partially or totally replace each other with regard to function, but they will not be expressed at the same time in the patient's life or in the same organ. In the future it may not be necessary to transfer a new gene; instead we may interfere with the regulation of another gene with a similar function.

Chromosomes, Artificial↗
PubMed2006

Ultrasound guided site specific gene delivery system using adenoviral vectors and commercial ultrasound contrast agents.

We have evaluated if ultrasound imaging (US) and various commercially available contrast microbubbles can serve as a non-invasive systemically administered delivery vehicle for site-specific adenoviral-mediated gene transfer in vitro and in vivo. The contrast agents were tested for their ability to enclose and to protect an adenoviral vector carrying the GFP marker gene (Ad-GFP) into the microbubbles. We have also evaluated the ability of the innate immune system to inactivate free adenoviruses as well as unenclosed viruses adsorbed on the surface of the contrast agents and in turn the ability of the microbubbles to enclose and to protect the viral vectors from such agents. In vitro as well as in vivo, innate components of the immune system were able to serve as inactivating agents to clear free viral particles and unenclosed adenoviruses adsorbed on the microbubbles' surface. Systemic delivery of Ad-GFP enclosed into microbubbles in the tail vein of nude mice resulted in specific targeting of the GFP transgene. Both fluorescence microscopy and GFP immunohistochemistry demonstrated US guided specific transduction in the targeted cells only, with no uptake in either heart, lungs or liver using complement-pretreated Ad-GFP microbubbles. This approach enhances target specificity of US microbubble destruction as a delivery vehicle for viral-mediated gene transfer.

Adenoviridae↗
PubMed2005

Lipid-mediated siRNA delivery down-regulates exogenous gene expression in the mouse brain at picomolar levels.

BACKGROUND: Efficient in vivo vectors are needed to exploit the enormous potential of RNA interference (RNAi). Such methods require optimisation for specific delivery routes, tissues and usages. We tested the capacity of different non-viral vectors and formulation methods for inhibition of exogenous (luciferase) gene expression when used to introduce small interfering RNA (siRNA) into the mouse brain in vivo. METHODS: Polyethylenimine (PEI)-based polyplexes and JetSI (a mixture of cationic lipids)-based lipoplexes were used to vectorise plasmid DNA encoding the firefly Photinus pyralis luciferase gene and picomolar amounts of siRNA directed against this gene. Two controls were used, DNA encoding an unrelated luciferase from Renilla reniformis and a mutated siRNA sequence. RESULTS: First, we found that linear PEI, although efficient for delivering nucleic acids to cells, did not permit development of siRNA activity within the dose range tested (<0.5 pmol). Second, various combinations of cationic lipids were tried and the best formulation was found to be a combination of JetSI with the fusogenic lipid dioleoylphosphatidylethanolamine (DOPE). Efficient inhibition of target, firefly luciferase was obtained with exceedingly low amounts of siRNA: 78 +/- 6% inhibition at 24 h post-transfection with 0.2 pmol siRNA. This inhibition was dose-dependent and specific. No effect was seen on the control gene, co-transfected Renilla luciferase, and the control mutated siRNA sequence had no effect on the targeted firefly luciferase. CONCLUSIONS: We have optimised an efficient cationic lipoplex method for delivery of siRNA into the newborn mouse brain. Specific inhibition of exogenous target gene expression is obtained with picomolar amounts of siRNA.

Analysis of Variance↗
PubMed2006

A new generation of retroviral producer cells: predictable and stable virus production by Flp-mediated site-specific integration of retroviral vectors.

We developed a new strategy that provides well-defined high-titer producer cells for recombinant retroviruses in a minimum amount of time. The strategy involves the targeted integration of the retroviral vector into a chromosomal locus with favorable properties. For proof of concept we established a novel HEK293-based retroviral producer cell line, called Flp293A, with a single-copy retroviral vector integrated at a selected chromosomal locus. The vector was flanked by noninteracting Flp-recombinase recognition sites and was exchanged for different retroviral vectors via Flp-mediated cassette exchange. All analyzed cell clones showed correct integration and identical titers for each of the vectors, confirming that the expression characteristics from the parental cell were preserved. Titers up to 2.5 x 10(7) infectious particles/10(6) cells were obtained. Also, high-titer producer cells for a therapeutic vector that encodes the 8.9-kb collagen VII cDNA in a marker-free cassette were obtained within 3 weeks without screening. Thus, we provide evidence that the precise integration of viral vectors into a favorable chromosomal locus leads to high and predictable virus production. This method is compatible with other retroviral vectors, including self-inactivating vectors and marker-free vectors. Further, it provides a tool for evaluation of different retroviral vector designs.

Animals↗
PubMed2000

Adenoviral gene transfer of basic fibroblast growth factor promotes angiogenesis in rat brain.

Cerebral ischemic disease often causes morbidity and mortality, while the induction of new blood vessels is expected to provide a therapeutic effect in this occlusive cerebrovascular disease. In this study, we utilized two replication-deficient adenoviral vectors containing cDNA from basic fibroblast growth factor (bFGF), a well-known angiogenic factor, and examined whether biological angiogenic activity of adenovirally gene-transferred bFGF could be observed in the rat brain. One vector contained native cDNA from bFGF without the secretory signal sequence and the other contained the same cDNA fused with an interleukin-2 secretory signal sequence. After ventricular administration of these viral vectors, gene-transferred cells demonstrated a high immunoreactivity against the anti-bFGF antibody and a remarkably high concentration of bFGF was detected in the cerebrospinal fluid. A semiquantitative analysis of angiogenic activity revealed that bFGF gene transfer induced angiogenesis in normal rat brains, with a more pronounced angiogenic effect seen with the vector of a secreted form than with the vector without a secretory signal sequence. These results suggest that bFGF gene transfer using these adenoviral vectors might be useful for the treatment of ischemic cerebrovascular disease.

Adenoviridae↗
PubMed2003

Therapeutic HIV vaccines.

Antiretroviral therapy with potent combinations of drugs has been responsible for a significant decline in the occurrences of AIDS defining conditions and death in the developed world. However, therapy requires life-long use and is complicated by relatively high failure rates, significant toxicities, adherence difficulties and the development of resistance. The combination of these complications of therapy and the availability of this treatment to only 1 in 20 of the estimated 34 million people infected world wide has prompted us to reconsider the current strategies for achieving the goals of HIV therapy. A more rational approach to therapeutic interactions is needed, particularly with respect to therapy in the developing world, with the focus shifted towards maintaining relative viral control over the long term. One potential mechanism to attain viral control over the long term is the use of therapeutic vaccines. This chapter will review the scientific rationale for therapeutic HIV-1 vaccines and the vaccines that have been evaluated as a therapeutic to date including recombinant envelope glycoproteins, inactivated envelope depleted virus, regulatory proteins such as Tat, cytokines such as IFN-(alpha), DNA vaccines, and live viral vectors. Although the future role of therapeutic vaccines in the treatment of HIV-1 remains to be determined, at a minimum this immunomodulatory approach will provide new insights into fundamental viral-host cell interactions and the pathogenesis of HIV-1. Yet even more notable, is that, if successful, a therapeutic vaccine product would be inexpensive and rapidly exportable representing a treatment strategy for people living with HIV infection worldwide.

AIDS Vaccines↗
PubMed1994

Ribozyme-mediated in vitro cleavage of transcripts arising from the major transforming genes of human papillomavirus type 16.

Human papillomaviruses (HPV) have been strongly implicated as important cofactors in the development of several human malignancies, particularly anogenital carcinomas. Products arising from the E6 and E7 open reading frames (ORFs) from HPV-16, a type commonly associated with human cervical carcinoma, are essential for viral transformation. Unfortunately, a highly effective treatment for this infection is not available. To develop a novel treatment for this disease, ribozymes were designed to cleave all transcripts encoding HPV-16 E6 and E7 ORFs in proximity to their translational start sites ("AUG"). Cleavage sites for Rz110 and Rz558 occur immediately 3' to nucleotides 110 and 558 of the viral genomic DNA, respectively. Oligonucleotides corresponding to these ribozymes were synthesized and inserted into a eucaryotic viral vector derived from the nonpathogenic parvovirus, adeno-associated virus. Ribozyme transcription from this vector, termed CWRT7:SVN, is under control of both the highly active Rous sarcoma virus long terminal repeat and bacteriophage T7 promoters. T7 transcripts of the E6 and E7 ribozymes efficiently cleaved their cognate targets in vitro under a variety of conditions, including physiological temperature. These results may provide the basis for the development of a ribozyme-based, gene therapeutic treatment for HPV-associated diseases.

Avian Sarcoma Viruses↗
PubMed1997

Increased injection number enhances adenoviral genetic radiotherapy.

Intratumoral injection of an adenoviral vector containing radiation-inducible DNA sequences of the early growth response gene (Egr-1) promoter ligated to a cDNA encoding tumor necrosis factor-alpha (TNF-alpha; Ad.Egr-TNF) increases the radiation killing of a human radioresistant xenograft (SQ-20B). Viral dose-escalation experiments demonstrated that SQ-20B growth inhibition correlated with viral titer. Injection of 5 x 10(8) PFU Ad.Egr-TNF produced regression to a mean volume of 22 +/- 13% of the original tumor volume, 1 x 10(8) PFU to a mean of 62 +/- 24%, and 5 x 10(7) PFU to a mean of 67 +/- 27%. No regression was observed when tumors were injected with 1 x 10(7) PFU Ad.Egr-TNF or with the null viral vector (Ad.null). When two injections of vector (2 x 10(8) PFU Ad.Egr-TNF) were combined with 50 Gy, a significant increase in tumor regression was observed compared with injection of buffer, Ad.Egr-TNF, or 50 Gy. The interactive killing between TNF and radiation was enhanced significantly (P = 0.05) when the number of injections was increased from two to five while maintaining a constant viral titer (2 x 10(8) PFU Ad.Egr-TNF) and a constant radiation dose (50 Gy). Significant TNF-alpha levels were present in irradiated vs. unirradiated tumors following injection with Ad.Egr-TNF. Taken together, these data suggest that the volumetric reduction produced by the combined effects of Ad.Egr-TNF and radiation is enhanced with increasing vector concentration and the number of vector injections.

Adenoviridae↗
PubMed1997

Intracoronary adenovirus-mediated transfer of immunosuppressive cytokine genes prolongs allograft survival.

BACKGROUND: Intracoronary transfer and expression of recombinant genes in the intact heart is now feasible. In the transplant setting, local modulation of host immune responses by a genetically modified allograft may offer an attractive alternative to systemic immunosuppression. METHODS: We tested the efficacy and in vivo effect of intracoronary transfer of two immunosuppressive cytokine genes. First-generation E1-deleted adenoviral vectors expressing the Epstein-Barr virus interleukin-10 (AdSvIL10) or human transforming growth factor--beta 1 (AdCMVTGF-beta) were used. Rabbit cardiac allografts were transduced during cold preservation by slow (1 ml/min) intracoronary infusion of 10(10) pfu/gm diluted viral vectors and then implanted heterotopically. Controls included E1-deleted adenovirus (Ad5dI434) and AdCMVLacZ. Beating allografts were collected on day 4 for analysis of gene transfer efficacy and distribution. Additional grafts were used for evaluation of alloreactivity (n = 34). RESULTS: Mean allograft viral uptake was 81% (up to 91%). Polymerase chain reactions and reverse transcription-polymerase chain reactions confirmed the presence and expression of both genes in the grafts. beta-Galactosidase staining in AdCMVLacZ-infected grafts demonstrated efficient gene expression, which was highest (100%) in subepicardial regions. More homogeneous transmyocardial distribution of the transgene (in 25% to 40% of cells) could be achieved by pulsatile slow delivery. Allograft survival was 6.9 +/- 0.9 days in controls (n = 12), 11.1 +/- 1.7 days in AdCMVTGF-beta-infected grafts (n = 11, p < 10(-4)), and 11.2 +/- 3 days in AdSvIL10-infected grafts (n = 11, p < 10(-4)). Histologic scores (blinded) showed significantly (p < 0.005) higher regression coefficients for rejection in controls compared with both cytokine-transduced groups. Perioperative administration of cyclosporine A (INN: ciclosporin) to recipients had no effect on survival of AdCMVTGF-beta-infected grafts but reduced survival of AdSvIL10-infected grafts. CONCLUSIONS: Intracoronary gene transfer of immunosuppressive cytokines to cardiac allografts is efficient and effectively prolongs graft survival. Vectors that would induce long-term expression of such genes may make this approach clinically applicable.

Adenoviridae↗
PubMed1994

An in vitro ligation and transfection system for inserting DNA sequences into the latency-associated transcripts (LATs) gene of herpes simplex virus type 1.

This report describes a simple, rapid and highly efficient method for introducing specific DNA sequences into a defined locus of the herpes simplex virus type 1 (HSV-1) genome by restriction enzyme cleavage and ligation. The genome of the HSV-1 strain HFEM contains a 4.1 kb deletion in one copy of the RL region, deleting one copy of the latency-associated transcript (LAT) gene. It does not contain any site for restriction enzyme PacI. Two unique PacI restriction enzyme sites flanking an HSV-1 ICP6 promoter-LacZ reporter gene cassette were engineered into the LAT region to generate a recombinant virus HFEM/ICP6-LacZ which produced blue plaques in the presence of X-gal. This viral vector allowed the insertion of foreign genes directly into the HSV-1 genome by restriction enzyme digestion and ligation. The system was tested by digesting the HFEM/ICP6-LacZ DNA with PacI and with SwaI (an endogenous unique restriction enzyme site upstream of the LAT promoter locus and inserting by in vitro ligation a LAT promoter-LacZ gene cassette into the HFEM/ICP6-LacZ genome. The new recombinant virus HFEM/LAT-LacZ was detected as white plaques in the presence of X-gal, since beta-galactosidase expression, when driven by the LAT promoter, is not detectable during viral replication in tissue culture. The high yield (approximately 100%) of the recombinant virus obtainable from this in vitro ligation and transfection procedure coupled with a blue-white or reversible white-blue plaque detection scheme makes this a powerful method for constructing HSV-1 vectors around the LAT promoter locus.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2005

Identification of amino acids of Sindbis virus E2 protein involved in targeting tumor metastases in vivo.

Previous studies conducted in our laboratory with Sindbis viral vectors in animal models demonstrated excellent in vivo targeting of tumor cells and significant reduction of metastatic implant size. To explore the influence of Sindbis strain on these factors, we constructed new plasmids from the wild-type Ar-339 Sindbis virus strain and compared their sequences. We found differences in the replicase and envelope proteins between JT, HRSP, and Ar-339 sequences. We made chimeras combining both strains and studied their efficiency in SCID mice bearing tumor xenograft using IVIS in vivo imaging techniques. We found that JT envelope proteins targeted tumors more efficiently than those of Ar-339, while the Ar-339 replicase showed increased efficacy in tumor reduction. To determine which residues are responsible for tumor targeting, we made mutants of Ar-339 E2 envelope protein and tested them by IVIS imaging in ES-2 tumor-bearing and tumor-free mice. The change of only one amino acid from E70 to K70 in Ar-339 E2 suppressed the ability to target metastatic tumor implants in mice. A K70 and V251 double E2 mutant did not reverse the loss of targeting capability. Only the mutant with JT E2 and Ar-339 helper targeted tumor, though with less intensity.

Amino Acid Sequence↗
PubMed2001

Replication-selective virotherapy for cancer: Biological principles, risk management and future directions.

In the search for novel cancer therapies that can be used in conjunction with existing treatments, one promising area of research is the use of viral vectors and whole viruses. This review describes the underlying biological principles and current status of the field, outlines approaches for improving clinical effectiveness and discusses the unique safety and regulatory issues surrounding viral therapies.

Biological Therapy↗
PubMed1998

Gene transfer into human umbilical cord blood-derived CD34+ cells by particle-mediated gene transfer.

Delivery of genes into hematopoietic progenitor cells offers an attractive means for the introduction of corrective or protective genes into cells of both the myeloid and lymphoid lineage. Previously, investigators have often used murine retroviral vectors for gene delivery which require cells to be cycling for efficient delivery. We describe a nonviral method of gene delivery using particle-mediated gene transfer to obviate many disadvantages of viral vectors related to safety, production costs and the need for cell cycle proliferation. Using a CMV-CAT reporter plasmid, we show transfection of highly purified CD34+ cells isolated from umbilical cord blood. Effective gene transfer was shown in unstimulated and in growth-stimulated cells. Following transfection with a neomycin resistance gene, differentiation into cells of the myeloid lineage was observed, assayed by CFU-GM in the presence of G-418. Both unstimulated and stimulated cells gave rise to CFU-GM in the presence of G-418, indicating that stable expression of the neomycin resistance gene was maintained in early progenitors. These results demonstrate that particle-mediated gene transfer into human hematopoietic cells from umbilical cord blood can be achieved without affecting their CFU-GM differentiation potential. This gene transfer method offers an alternative approach to gene therapy studies involving human hematopoietic progenitor cells.

Anti-Bacterial Agents↗
PubMed1997

Increased contact time improves adenovirus-mediated CFTR gene transfer to nasal epithelium of CF mice.

Multiple dosing with recombinant adenoviral vectors containing the cystic fibrosis transmembrane conductance regulator (CFTR) cDNA to the nasal mucosa of cystic fibrosis (CF) transgenic mice reportedly results in only partial correction of the CF defect in chloride (Cl-) secretion without normalizing sodium (Na+) hyperabsorption, perhaps indicating inefficient gene transfer into the nasal airway epithelium in vivo. In this study, we have examined whether optimizing vector administration such as contact time could improve gene transfer efficiency. Changes in basal nasal potential difference (PD), and in PD (delta PD) following addition of amiloride and subsequent removal of Cl- from the luminal perfusate were assayed. As reported previously, the basal nasal PD was significantly more negative in CF mice (-24.9 +/- 2.1 mV) than in normal mice (-6.3 +/- 1.2 mV). Normal mouse nasal mucosa exhibited a large hyperpolarization in response to low Cl- substitution (delta PD of 8.5 +/- 1.9 mV), whereas the nasal mucosa of the CF mouse depolarized in response to this treatment. No correction of either the Cl- or Na+ transport defects were observed when 5 x 10(9) IU of Ad2/CFTR-5 were administered to the nasal passage of CF mice over a period of 5-20 min. However, when CF mice were perfused over a period of 60 min with the same dose of vector, a significant response (delta PD of 5.9 +/- 1.1 mV) to low Cl- substitution was detected 2 days later. In these mice, the basal nasal PD (-10.5 +/- 1.4 mV) and the response to amiloride were also reduced, indicating a partial correction of the Na+ transport defect. Expression of functional CFTR activity was transient with no measurable delta PD signals observed by day 7 post-treatment. These results suggest that prolonging the contact between an adenoviral vector and the respiratory epithelium enhances the efficiency of gene transfer and can result in improved correction of the CF Na+ and Cl- ion transport defects. Therefore, strategies that improve internalization of viral vectors and that prolong their contact time with target cells may result in the improved clinical efficacy of such vectors.

Adenoviridae↗
PubMed2005

Comparative efficacy of intratracheal adeno-associated virus administration to newborn rats.

Transient local overexpression of genes that promote lung defense or repair may help to protect or promote alveolar development in premature neonates. We showed that the use of adenoviral vectors in neonates was limited by the induction of lung growth disorders. In the present work we compare the efficiency of gene transfer to the neonatal lung by three adeno-associated viral vectors: rAAV1, rAAV2, and rAAV5. Transduction efficiency was first measured in vitro, by infecting A549 immortalized human lung epithelial cells, and primary epithelial and mesenchymal cells isolated from human fetal lung. AAV vectors yielded similar low levels of luciferase gene expression in the different cell types. In vivo transduction efficiency was evaluated in newborn rats, with AAV-LacZ vectors being intratracheally instilled at 3 days of age. Both rAAV5 and rAAV1, but not rAAV2, induced significant lung beta-galactosidase expression, which persisted on day 35. Highest beta- galactosidase levels were measured with rAAV5, but remained far lower than those obtained with adenoviral vectors. A transient increase in alveolar macrophages was observed on day 6, but not on day 8, after rAAV5-LacZ instillation. Morphometric evaluation of lung structures was performed on day 21, and showed no altered lung growth. We conclude that rAAV1 or rAAV5 was more efficient at mediating gene transfer in the neonatal lung than was rAAV2, without adversely affecting lung development. However, in vivo transgene expression was relatively low, and needs to be improved for future therapeutic use of these adeno-associated vectors.

Animals↗
PubMed2000

Long-term differential modulation of genes encoding orexigenic and anorexigenic peptides by leptin delivered by rAAV vector in ob/ob mice. Relationship with body weight change.

We investigated the long-term effects of physiological levels of leptin produced by gene therapy on body weight (BW) and expression of genes that encode orexigenic and anorexigenic peptides in the hypothalamus. Recombinant adeno-associated viral vector (rAAV), a non-pathogenic and non-immunogenic vector, encoding leptin (betaOb) was generated and administered iv to ob/ob mice lacking endogenous leptin. Whereas the lowest dose of rAAV-betaOb (6x10(9) particles) was ineffective, the middle dose (6x10(10) particles) curbed BW gain without affecting food consumption for 75 days of observation. A ten-fold higher dose (6x10(11) particles) resulted in increased blood leptin levels and suppressed both BW gain and food consumption throughout the duration of the experiment. rAAV-betaOb doses that either curbed BW without affecting food consumption or evoked BW loss and reduced food intake, decreased the expression of genes encoding the orexigenic peptides, neuropeptide Y and agouti-related peptide in the ARC, and the two doses were equally effective. Concomitantly, the expression of genes encoding the anorexigenic peptide, alpha-melanocyte stimulating hormone and cocaine-and-amphetamine regulatory transcript, was augmented with the latter gene displaying a dose-dependant response. These results document the efficacy of delivering biologically active leptin for extended periods by an iv injection of rAAV-betaOb and show that physiological leptin concentrations simultaneously exert a tonic inhibitory effect on orexigenic and a stimulatory effect on anorexigenic signaling in the hypothalamus. This intricate dynamic interplay induced by leptin regulates BW with or without an effect on food intake in leptin-deficient ob/ob mice. Further, these results suggest that gene therapy is an effective mode of delivery to the hypothalamus of those therapeutic proteins that cross the blood-brain barrier to ameliorate neuroendocrine disorders.

Agouti-Related Protein↗