PubMed Health⌕ Search

Biomedical subjects

David J Fink

Publications and source records attributed to David J Fink.

At least 19 recordsLinked to original sources
PubMed2005

Gene transfer of glutamic acid decarboxylase reduces neuropathic pain.

We tested whether transfer of the gene coding for glutamic acid decarboxylase to dorsal root ganglion using a herpes simplex virus vector to achieve release of GABA in dorsal horn would attenuate nociception in this condition. Subcutaneous inoculation of a replication-defective herpes simplex virus vector expressing glutamic acid decarboxylase (vector QHGAD67) 7 days after selective L5 spinal nerve ligation reversed mechanical allodynia and thermal hyperalgesia; the antiallodynic effect lasted 6 weeks and was reestablished by reinoculation. QHGAD67 inoculation also suppressed induction of c-Fos and phosphorylated extracellular signal-regulated kinase 1 and 2 in the spinal cord.

Animals↗
PubMed2005

Long-term neuroprotection achieved with latency-associated promoter-driven herpes simplex virus gene transfer to the peripheral nervous system.

We examined the ability of the herpes simplex virus (HSV) latency-associated promoter (LAP2) to drive biologically relevant prolonged transgene expression in the peripheral nervous system. Rat dorsal root ganglia were transduced in vivo by subcutaneous inoculation of replication-incompetent HSV-based vectors containing nerve growth factor (NGF) or neurotrophin-3 (NT-3) under the control of LAP2 (vectors SLN and QLNT3, respectively) and vector SHN expressing NGF under the control of the human cytomegalovirus immediate early promoter. Twenty-four weeks later a pure sensory neuropathy was induced by overdose of pyridoxine (PDX), and the animals were assessed 6 months after inoculation. Inoculation of SLN, but not SHN, attenuated the nerve damage caused by PDX and protected foot sensory amplitude, H-wave amplitude, and behavioral measures of proprioceptive function. QLNT3 was more effective than SLN in preserving the largest myelinated fibers from degeneration. These results indicate that expression of NGF or NT-3 driven by LAP2 is sufficient to prevent the development of neuropathy 6 months after vector inoculation in rats.

Animals↗
PubMed2005

Use of laser capture microdissection together with in situ hybridization and real-time PCR to study distribution of latent herpes simplex virus genomes in mouse trigeminal ganglia.

The herpes simplex virus (HSV) frequently establishes a latent state in neurons, which can then be reactivated from the infected neurons. Quantifying the single-cell viral load is essential for understanding latency and reactivation of this virus. In this chapter the methods of laser capture microdissection and quantitative real-time polymerase chain reaction with in situ hybridization have been combined to determine the HSV copy number per neuron in latently infected trigeminal ganglia. The distribution of latent herpes simplex genomes at the individual cell level has been deteremined and the relationship of the number of latent genomes to the expression of latency-associated transcripts established.

Animals↗
PubMed2005

Replication-defective genomic HSV gene therapy vectors: design, production and CNS applications.

Herpes simplex virus (HSV) is a neurotropic double-stranded DNA virus. In an unmodified form it is a human pathogen, causing recurrent cold sores, keratitis and, rarely, severe encephalitis. Elimination of pathogenic functions results in the generation of a valuable gene transfer vector for neurological applications. Replication-defective genomic HSV-based vectors are highly infectious, and efficiently transduce and express transgenes in a broad range of both dividing and non-dividing cells. Clinically relevant yields of clinical grade vector can be produced by growth in cell lines that complement the viral functions that are deleted in the vectors to eliminate pathogenicity. The viral genome is over 150 kb in length and many of the viral genes may be deleted without compromising viral growth in vitro, and therefore large or multiple transgenes can be accommodated within the vectors. The wild-type virus adopts a lifelong latent state in neurons of sensory ganglia. This property can be exploited in the generation of vectors to allow long-term transgene expression in neurons. In this review, we summarize recent progress in the areas of vector development and vector production, and in developing gene transfer therapeutics to treat malignant glioma.

Animals↗
PubMed2004

Protective effect of herpes simplex virus-mediated neurotrophin gene transfer in cisplatin neuropathy.

Attempts to develop clinical treatments for neuropathy using neurotrophins have not been successful. We tested whether neurotrophin gene delivery to dorsal root ganglia (DRGs) using non-replicating herpes simplex virus (HSV)-based vectors could prevent the development of neuropathy caused by administration of cisplatin. Following subcutaneous inoculation of HSV vectors expressing nerve growth factor (NGF) or neurotrophin-3 (NT-3), neurons in the DRG were transduced to produce NGF or NT-3 in vivo. Inoculation of either the NGF- or the NT-3-expressing vectors 3 days before the start of a 6-week course of cisplatin treatment protected against cisplatin-induced neuropathy assessed by electrophysiological, histological and behavioural measures 2 months later. Iatrogenic neuropathy caused by administration of chemotherapeutic drugs represents an excellent target for a human trial to assess the potential of gene therapy to prevent neuropathy.

Animals↗
PubMed2004

Prolonged biologically active transgene expression driven by HSV LAP2 in brain in vivo.

Herpes simplex virus (HSV) naturally establishes a life-long latent state in neurons, characterized by the expression of latency-associated transcripts (LATs) in the absence of viral lytic functions, and the latency-associated promoter (LAP2) has been identified as a moveable element responsible for the expression of LATs from latent HSV genomes. Prolonged transgene expression will be required for the treatment of chronic diseases of the CNS using HSV vectors. We therefore examined the ability of LAP2 to drive prolonged expression of a biologically active transgene from latent HSV vector genomes in brain in vivo using the 6-hydroxydopamine (6-OHDA) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) models of Parkinson disease. A replication-incompetent HSV vector containing the glial cell-derived neurotrophic factor (GDNF) under the control of LAP2 was injected into the substantia nigra and 5 and a half months later 6-OHDA was injected into the striatum. GDNF expression from the vector preserved dopaminergic function measured by histology and behavior 6 months after vector inoculation. Mice inoculated with the LAP2-GDNF replication-incompetent HSV vector followed by 3 months of daily low-dose MPTP injections were substantially protected against the consequences of that treatment measured by weekly behavioral testing and histologic measures at the conclusion of the experiment. These studies using subacute and chronic models of neurodegeneration demonstrate that the HSV LAP2 promoter element provides prolonged expression of relevant amounts of a transgene to produce significant biological effects in brain in vivo over the course of many months.

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed2004

Peripherally delivered glutamic acid decarboxylase gene therapy for spinal cord injury pain.

Neuropathic pain after spinal cord injury (SCI) represents a difficult problem that is commonly refractory to conventional medical management. To determine if spinal release of gamma-amino butyric acid (GABA) could reduce below-level central neuropathic pain after SCI, we constructed a replication-incompetent herpes simplex virus (HSV)-based vector encoding one isoform of human glutamic acid decarboxylase (GAD67). Dorsal root ganglion (DRG) neurons transduced in vitro or in vivo by subcutaneous inoculation produced GAD and released GABA constitutively. T13 spinal cord hemisection resulted in central neuropathic pain manifested by mechanical allodynia and thermal hyperalgesia. Subcutaneous inoculation of the vector into both feet reduced both manifestations of below-level SCI pain; the vector-mediated effect was partially reversed by intrathecal bicuculline or phaclofen at doses that did not affect thresholds in normal or injured uninoculated animals. Vector-mediated GABA release attenuated the increase in spinal calcitonin gene-related peptide immunoreactivity caused by cord hemisection. These results suggest that HSV-mediated gene transfer to DRG could be used to treat below-level central neuropathic pain after incomplete SCI.

Animals↗
PubMed2004

Central sprouting of uninjured small fiber afferents in the adult rat spinal cord following spinal nerve ligation.

Partial nerve injury results in chronic pain that is difficult to treat effectively. To investigate the anatomic basis of this phenomenon we used wheat germ agglutinin-horseradish peroxidase (WGA-HRP) to label the central projections of uninjured small fibers (Adelta and C) in a well-established model of neuropathic pain created by selective spinal nerve ligation in the adult. We found extensive sprouting of uninjured WGA-HRP-labeled afferents into the central termination field in lamina II of dorsal horn normally occupied by L5 afferents whose peripheral axons had been ligated distal to the dorsal root ganglion. The formation of new projections by uninjured fibers into a functionally but not anatomically deafferented field in the adult may play a role in the development of chronic pain.

Afferent Pathways↗
PubMed2004

Herpes vector-mediated gene transfer in treatment of diseases of the nervous system.

Vectors constructed from recombinant herpes simplex virus (HSV) have special utility for gene transfer to the nervous system. Nonreplicating vectors created by deletion of essential immediate early genes can be propagated to high titers on complementing cell lines that provide the missing gene product(s) in trans. Direct inoculation of these vectors into neural parenchyma is effective in rodent models of brain tumor, Parkinson disease, spinal cord injury, and spinal root trauma. Subcutaneous inoculation of the HSV vectors can be used to transduce neurons of the dorsal root ganglion to provide a therapeutic effect in models of polyneuropathy and chronic regional pain. In human trials, direct injection of replication-competent HSV into brain tumors has proven safe. Human trials of nonreplicating HSV gene transfer by direct inoculation for treatment of glioblastoma and HSV gene transfer by subcutaneous inoculation for the treatment of chronic intractable pain should commence soon.

Animals↗
PubMed2004

Delivery using herpes simplex virus: an overview.

The human herpesviruses represent excellent candidate viruses for several types of gene vector applications. As a class, they are large DNA viruses with the potential to accommodate large or multiple transgene cassettes, and they have evolved to persist in a lifelong nonintegrated latent state without causing disease in the immune-competent host. Among the herpesviruses, herpes simplex virus type 1 (HSV-1) is an attractive vehicle because in natural infection, the virus establishes latency in neurons, a state in which viral genomes may persist for the life of the host as intranuclear episomal elements. The natural lifelong persistence of latent genomes in trigeminal ganglia (TG) without the development of sensory loss or histologic damage to the ganglion attests to the effectiveness of these natural latency mechanisms. Although the wild-type virus may be reactivated from latency under the influence of a variety of stresses, completely replication defective viruses can be constructed that retain the ability to establish persistent quiescent genomes in neurons, but that are unable to subsequently reactivate in the nervous system. These persistent genomes are devoid of lytic gene expression, but retain the ability to express latency-associated transcripts (LATs).

Animals↗
PubMed2004

Delivery of herpes simplex virus-based vectors to the nervous system.

Gene transfer to the nervous system is an attractive option to treat a wide variety of neurological insults. The expression of trophic factor and/or antiapoptotic genes may be beneficial in halting the slow neurodegeneration in such conditions as Parkinson's disease (4,5), the rapid neuronal cell death following trauma to the brain or spinal cord (6,7), or in treating peripheral neuropathies associated with diabetes or use of chemotherapeutic agents (8,9). Introduction of dominant-negative mutant genes or antisense RNA to treat diseases such as Huntington's disease, or transfer of genes to replace lost or mutated endogenous proteins to treat disorders such as lysosomal storage diseases, may prove useful. In addition, gene transfer to overexpress endogenous antinociceptive proteins has great potential in pain management. The problem faced by all of these applications is finding a suitable methodology that will facilitate the transfer of exogenous genes to the appropriate nerve cells; virusbased vectors have proven quite efficient in transferring genes to many different cell types.

Animals↗
PubMed2004

Delivery of herpes simplex virus-based vectors to stem cells.

In contrast to traditional drugs that generally act by altering existing gene product function, gene therapy aims to target the root cause of the disease by altering the genetic makeup of the cell to treat the disease. Researchers have adapted several classes of viruses as gene-transfer vectors, taking advantage of natural viral mechanisms designed to efficiently and effectively deliver DNA to the host-cell nucleus. Among these, the human herpesviruses are excellent candidate vectors for a variety of applications. Herpes simplex virus type 1 (HSV-1) is a particularly attractive gene-transfer vehicle because natural infection in humans includes a latent state in which the viral genome persists in a nonintegrated form without causing disease in an immune-competent host. HSV-1 is a large DNA virus with a broad host range that can be engineered to accommodate multiple or large therapeutic transgenes (4). HSV vectors may be generally useful for gene transfer to a variety of tissues in which short-term or extended transgene expression of therapeutic transgenes achieve a therapeutic effect. We have used therapeutic vectors to successfully treat human disease models in animals, including cancer, Parkinson's disease, and nerve damage (5-10).

Animals↗
PubMed2003

Stem cell therapy in a caprine model of osteoarthritis.

OBJECTIVE: To explore the role that implanted mesenchymal stem cells may play in tissue repair or regeneration of the injured joint, by delivery of an autologous preparation of stem cells to caprine knee joints following induction of osteoarthritis (OA). METHODS: Adult stem cells were isolated from caprine bone marrow, expanded in culture, and transduced to express green fluorescent protein. OA was induced unilaterally in the knee joint of donor animals by complete excision of the medial meniscus and resection of the anterior cruciate ligament. After 6 weeks, a single dose of 10 million autologous cells suspended in a dilute solution of sodium hyaluronan was delivered to the injured knee by direct intraarticular injection. Control animals received sodium hyaluronan alone. RESULTS: In cell-treated joints, there was evidence of marked regeneration of the medial meniscus, and implanted cells were detected in the newly formed tissue. Degeneration of the articular cartilage, osteophytic remodeling, and subchondral sclerosis were reduced in cell-treated joints compared with joints treated with vehicle alone without cells. There was no evidence of repair of the ligament in any of the joints. CONCLUSION: Local delivery of adult mesenchymal stem cells to injured joints stimulates regeneration of meniscal tissue and retards the progressive destruction normally seen in this model of OA.

Animals↗
PubMed2003

Enhanced functional recovery after proximal nerve root injury by vector-mediated gene transfer.

In order to test the functional implication of herpes simplex virus (HSV) vector-mediated gene transfer after axonal injury, we injected replication-incompetent HSV vectors coding for the anti-apoptotic peptide Bcl-2 and the glial cell-derived neurotrophic factor (GDNF), separately or in combination into ventral spinal cord 30 min after a crush injury to the proximal spinal root that was combined with moderate mechanical traction. HSV-mediated expression of Bcl-2 or GDNF enhanced functional recovery assessed by histologic, electrophysiologic, and behavioral parameters up to 5 months after injury. The most sensitive measure of distal motor function, the sciatic function index, was significantly improved in animals injected with the two vectors together. These results suggest an approach to root trauma that might be used to enhance functional recovery after injury.

Animals↗
PubMed2003

Development of HSV-mediated gene transfer for the treatment of chronic pain.

Chronic pain is often difficult to treat effectively. We have exploited the high affinity of herpes simplex virus (HSV) for peripheral sensory neurons to create HSV-based vectors for the treatment of chronic pain. We have demonstrated that an HSV-based vector expressing proenkephalin reduces pain-related responses in rodent models of inflammatory pain, neuropathic pain, and pain resulting from cancer in bone. A human trial has been proposed.

Animals↗
PubMed2003

Therapeutic gene transfer with herpes-based vectors: studies in Parkinson's disease and motor nerve regeneration.

We have examined the possibility of using herpes simplex virus (HSV)-based vectors to prevent neuronal cell death and enhance functional recovery after injury. In the 6-hydroxydopamine (6-OHDA) model of Parkinson's disease (PD) and after proximal spinal root injury, direct stereotactic injection of HSV-based vectors constructed to express the glial cell derived neurotrophic factor (GDNF) or the anti-apoptotic peptide Bcl-2 prevented neuronal death and enhanced recovery. Gene transfer may be useful in the treatment of neurologic disorders in which neuronal cell death occurs in a restricted anatomic distribution.

Animals↗
PubMed2003

Transgene-mediated enkephalin release enhances the effect of morphine and evades tolerance to produce a sustained antiallodynic effect in neuropathic pain.

We examined the pharmacologic characteristics of herpes simplex virus (HSV) vector-mediated expression of proenkephalin in the dorsal root ganglion in a rodent model of neuropathic pain. We found that: (i). vector-mediated enkephalin produced an antiallodynic effect that was reversed by naloxone; (ii). vector-mediated enkephalin production in animals with spinal nerve ligation prevented the induction of c-fos expression in second order sensory neurons in the dorsal horn of spinal cord; (iii). the effect of vector-mediated enkephalin enhanced the effect of morphine, reducing the ED(50) of morphine 10-fold; (iv). animals did not develop tolerance to the continued production of vector-mediated enkephalin over a period of several weeks; and, (v). vector transduction continued to provide an analgesic effect despite the induction of tolerance to morphine. This is the first demonstration of gene transfer to provide an analgesic effect in neuropathic pain. The pharmacologic analysis demonstrates that transgene-mediated expression and local release of opioid peptides produce some effects that are distinct from peptide analogues delivered pharmacologically.

Animals↗