Overexpression of IL-17 in the knee joint of collagen type II immunized mice promotes collagen arthritis and aggravates joint destruction.
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Animals↗
Biomedical subjects
J Kolls
Publications and source records attributed to J Kolls.
Effect of alcohol consumption on host release of interleukin-17 during pulmonary infection with Klebsiella pneumoniae.
BACKGROUND: A link between alcohol abuse and bacterial pneumonia has been recognized for centuries, but mechanisms to explain this relationship are unclarified. Interleukin-17 (IL-17) is a lymphocyte-derived cytokine that is part of the inflammatory cytokine cascade. Previous studies from our laboratory indicated that IL-17 is released in lung tissue in a murine model of bacterial pneumonia caused by Klebsiella pneumoniae. The effects of alcohol consumption on pulmonary release of IL-17 are unknown. METHODS: Mice were maintained on 20% ethanol in drinking water or on a control diet without alcohol. After 2 weeks, alcohol and control mice were challenged with intratracheal K. pneumoniae. Mice were followed for survival after bacterial challenge, neutrophil recruitment was assayed as myeloperoxidase, and IL-17 was measured in lung lavage fluid by enzyme-linked immunosorbent assay. In additional experiments, splenocytes from control mice were incubated with ethanol in vitro, and release of IL-17 was measured in culture supernatants. Finally, control and alcohol mice received intrapulmonary gene transfer of E-1-deleted adenovirus containing the murine IL-17 gene. These mice were then challenged with K. pneumoniae and followed for survival and neutrophil recruitment. RESULTS: In these studies, we demonstrate that a 2-week history of ethanol consumption in mice suppresses release of IL-17 into lung tissue, decreases neutrophil recruitment, and increases mortality from experimental K. pneumonia. In vitro experiments confirm a direct suppressive effect of ethanol on the release of IL-17 from splenocytes. In vivo administration of the IL-17 gene in an adenoviral vector to alcohol-consuming mice results in release of IL-17 into lavage fluid and normalizes neutrophil recruitment and mortality after bacterial challenge. CONCLUSIONS: The results of these experiments strongly implicate IL-17 as an important pathway for the immunosuppression associated with alcohol abuse and support gene therapeutic approaches to augment immune function in the alcoholic host or to treat infections associated with alcoholism.
Animals↗
Immune response after adenoviral gene transfer in syngeneic heart transplants: effects of anti-CD4 monoclonal antibody therapy.
BACKGROUND: E1-deleted adenoviral vectors are frequently used for in vivo gene therapy. However, gene expression after adenovirus-(ad) mediated gene transfer is known to be transient due to the generation of an immune response against virus-infected cells. In this study, we asked whether an anti-CD4 mAb (RIB 5/2) treatment may improve the gene transfer into rat cardiac grafts. METHODS: We injected recombinant ad-constructs encoding for Escherichia coli beta-gal into syngeneic rat heart transplants via the proximal aorta. One-half of the recipients of genetically modified grafts received the anti-CD4 mAb RIB 5/2, whereas the other half received no monoclonal antibody treatment. Genetically unmodified isografts without any treatment of the recipients were used as additional controls. At different time points hearts were harvested and analyzed for reporter gene expression, intragraft cellular infiltration, and cytokine gene expression (quantitative "real time" reverse transcriptase polymerase chain reaction). Serum samples were analyzed for anti-ad-Ig using enzyme-linked-immunosorbent-assay. RESULTS: In control animals the beta-gal reporter gene expression slowly increased until day 7 and then declined. The immunohistological and reverse transcriptase polymerase chain reaction intragraft analyses revealed a strong inflammatory response (cellular infiltration, cytokine expression) in ad-transfected grafts that may explain the delayed expression and fast down-regulation of the transgene. Treatment with RIB 5/2 mAb resulted in a faster and prolonged reporter gene expression, reduced graft infiltration, reduced anti-ad-Ig titers and less interferon-gamma up-regulation. CONCLUSIONS: Our results indicate that modulation of the anti-ad immune response using a nondepleting anti-CD4 mAb may increase the efficiency of ad-vectors for gene therapy in the transplant setting.
Adenoviridae↗
Murine CD4+ T lymphocyte subsets and host defense against Pneumocystis carinii.
The recruitment of specific subsets of CD4(+) T lymphocytes to the lungs in response to Pneumocystis carinii was investigated. For mice inoculated with P. carinii, an ELISPOT assay was used to calculate the numbers of lymph node and lung tissue CD4(+) cells that secreted interferon (IFN)-gamma (Th1 cytokine) and interleukin (IL)-4 (Th2 cytokine) after concanavalin A stimulation. An ELISA was used to assay culture supernatants for cytokine concentrations. Precursor frequency of both IFN-gamma- and IL-4-secreting cells was increased in lymph nodes at 1 week, whereas increases in Th1 and Th2 cells in lung tissue were delayed 3 weeks before declining. The frequency of IL-4-secreting cells always was greater than the frequency of IFN-gamma secreting cells. These results demonstrate an early T lymphocyte response in draining lymph nodes, followed by later recruitment of Th1 and Th2 lymphocytes into lung tissue. The overall CD4(+) T cell response to P. carinii involves both Th1 and Th2 subsets, but the response is Th2 dominant in both lymph node and lung tissue.
Animals↗
Stimulatory and inhibitory action of cytokines on the regulation of hCMV-IE promoter activity in human endothelial cells.
Viral promoters are commonly used as regulatory elements in gene therapy vectors due to their strong activity in various cell lines in vitro. However, transgene expression under the control of viral promoters in vivo has been shown to be limited to a short period of time. Several mechanisms for the transient expression of the delivered transgene may be important including deletion of transduced cells or promoter downregulation. Recently we reported that cytokines may either decrease or increase the activity of the human cytomegalovirus (hCMV) promoter in monocytes depending on the differentiation status of the transduced cells. For many applications, the gene of interest has to be delivered into an inflammatory milieu (tumour, ischaemia/reperfusion, vector-induced inflammation etc.). In this report we investigated the influence of various inflammatory cytokines on the hCMV-IE promoter activity in transduced human primary endothelial cells (Huvec) in vitro, which may be the first target cells after gene transfer into different organs. Cultured cells were infected with an E1-deleted adenoviral vector encoding for E. colibeta-galactosidase (Adbeta-gal) driven by the hCMV-IE promoter and incubated either with or without various cytokines. Our results indicate that interferon-gamma (IFN-gamma) and interleukin-10 (IL-10) downregulate promoter activity in endothelial cells whereas, in contrast, tumour necrosis factor (TNF-alpha), interleukin 1beta (IL-1beta) and interleukin 4 (IL-4) increased the promoter activity. These results suggest that inflammatory processes influence the in vivo expression of transferred viral promoter controlled genes of interest.
Cells, Cultured↗
Ischemia/reperfusion injury-mediated down-regulation of adenovirus-mediated gene expression in a rat heart transplantation model is inhibited by co-application of a TNFRp55-Ig chimeric construct.
E1-deleted adenoviral vectors are efficient vectors for somatic gene therapy. Recently, we have shown that intratracheal application of an adenoviral reporter construct leads to significant reporter gene expression in rat lungs within 24 h. In contrast, reporter gene expression in syngeneic rat heart transplants after adenovirus-mediated gene transfer was delayed. Since the adenovirus cannot replicate, down-regulation of the hCMV-IE promoter controlled reporter gene expression in initially infected cells by cytokines, which are released as a result of ischemia/reperfusion injury, might be involved. In order to investigate the role of proinflammatory cytokines, eg TNF-alpha in affecting hCMV-IE promoter-driven reporter gene expression, transient blockade of TNF-alpha was achieved by local co-application of an Ad-construct encoding for a soluble TNFRp55-Ig chimeric molecule in a syngeneic rat heart transplantation model. Co-application of the reporter construct together with the TNFRp55-Ig chimeric molecule significantly increased the early reporter gene expression after transplantation. Moreover, infiltration of inflammatory cells (T cells, macrophages, NK cells) and production of TNF-alpha in the transplant was markedly reduced. Our results indicate that: (1) proinflammatory cytokines are involved in down-regulation of reporter gene expression in ischemia/reperfusion injured tissues; and (2) inhibition of TNF-alpha might be a useful tool to increase early gene expression in gene therapy protocols, particularly in transplantation. Gene Therapy (2000) 7, 1238-1243.
Adenoviridae↗
Intragraft overexpression of interleukin-4 is neither sufficient nor essential for tolerance induction to cardiac allografts in a high-responder strain combination.
BACKGROUND: Recently we have demonstrated that the nondepleting anti-CD4 monoclonal antibody (mAb) RIB5/2 induces long-term acceptance of kidney and heart allografts in all rat strain combinations tested. Cytokine gene expression studies by reverse transcriptase-polymerase chain reaction revealed a reversed intragraft interleukin (IL)-4/interferon-gamma ratio. Whether IL-4 mediated immune deviation contributes to transplantation tolerance is not clear so far. METHODS: To learn more about the functional relevance of the relative IL-4 up-regulation, IL-4 was overexpressed in rat heart allografts by using ex vivo adenoviral gene transfer. The efficiency of gene transfer was analyzed by reporter gene assays as well by reverse transcriptase-polymerase chain reaction analysis of IL-4 mRNA expression. RESULTS: The intragraft overexpression of IL-4 did not prolong the allograft survival compared with controls. Moreover, neutralization of IL-4 by OX81 mAb did not prevent tolerance induction by RIB5/2 treatment. CONCLUSIONS: Anti-CD4 mAb-induced tolerance is associated with an intragraft type1/type2 shift, however, the up-regulation of IL-4 alone is neither sufficient nor essential to induce tolerance to cardiac allografts in a high-responder strain combination.
Animals↗
Adenovirus-mediated gene transfer of interleukin-4 to corneal endothelial cells and organ cultured corneas leads to high IL-4 expression.
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Adenoviridae↗
Direct adenovirus-mediated gene transfer of interleukin 1 and tumor necrosis factor alpha soluble receptors to rabbit knees with experimental arthritis has local and distal anti-arthritic effects.
Adenoviral vectors were used to deliver genes encoding a soluble interleukin 1 (IL-1)-type I receptor-IgG fusion protein and/or a soluble type I tumor necrosis factor alpha (TNFalpha) receptor-IgG fusion protein directly to the knees of rabbits with antigen-induced arthritis. When tested individually, knees receiving the soluble IL-1 receptor had significantly reduced cartilage matrix degradation and white blood cell infiltration into the joint space. Delivery of the soluble TNFalpha receptor was less effective, having only a moderate effect on white blood cell infiltration and no effect on cartilage breakdown. When both soluble receptors were used together, there was a greater inhibition of white blood cell infiltration and cartilage breakdown with a considerable reduction of synovitis. Interestingly, anti-arthritic effects were also seen in contralateral control knees receiving only a marker gene, suggesting that sustained local inhibition of disease activity in one joint may confer an anti-arthritic effect on other joints. These results suggest that local intra-articular gene transfer could be used to treat systemic polyarticular arthritides.
Adenoviridae↗
Gene therapy for malignant mesothelioma: a novel approach for an incurable cancer with increased incidence in Louisiana.
Malignant mesothelioma (MM) is a tumor of the pleura for which there is no satisfactory treatment. It is an almost universally fatal disease, regardless of the stage of the tumor at the time of diagnosis. Current treatment modalities include surgery, chemotherapy, and radiation therapy, although in some series none of these modalities is superior to no treatment at all. Because of the dismal prognosis for patients with MM, new modes of treatment are desperately needed. A promising area of research into the treatment of various malignancies is gene therapy. Recent studies have demonstrated the utility of exposing tumor cells to cells transduced to express the Herpes simplex virus gene for thymidine kinase (HSV-TK). By virtue of their expression of HSV-TK, the transduced cells are rendered susceptible to the antiviral drug, ganciclovir (GCV). Nearby untransduced tumor cells are killed by a so-called bystander effect. We are describing a Phase I clinical gene therapy trial for MM, which we are presently conducting at the Louisiana State University Medical Center of New Orleans. The purpose is to study the safety and to determine the maximal tolerated dose of an HSV-TK-transduced ovarian cancer cell line (PA1-STK cells) that is infused into the pleural cavities of patients. This infusion is followed by systemic administration of GCV. The hope is that administration of GCV will result in killing of both the transduced ovarian cancer cells as well as the nearby malignant cells.
Ganciclovir↗
Effect of alcohol on bacterial translocation in rats.
Bacterial translocation has been proposed to be important in the pathophysiology of sepsis, as well as to be a consequence of sepsis. To study the effect of alcohol on bacterial translocation from the gut, normal Sprague-Dawley rats were administered alcohol by gavage by two regimens: Acute (3.7 g/kg, one dose) or Subacute (1 of 2 doses, 2.4 or 3.7 g/kg/day once daily for 14 days). Mesenteric lymph node cultures were performed, and portal venous blood was assayed for endotoxin. Ileal and cecal permeability studies were performed in the Acute and Subacute groups using fluorescein isothiocyanate-labeled dextrans of either 4,000 or 70,000 kDa size. As an index of the effect of systemic endotoxin, tissues from mesenteric lymph nodes, liver, and intestinal Peyer's patches were assayed for the presence of mRNA for tumor necrosis factor. Additionally, because extrapulmonary sepsis has been shown to suppress pulmonary antibacterial defenses, animals in the Subacute group were challenged by aerosol inoculation with Pseudomonas aeruginosa to determine bacterial clearance and alveolar cellular responses. The results show that neither of the alcohol regimens resulted in bacterial growth from mesenteric lymph nodes or portal blood. Animals in the Subacute group had more endotoxin present in portal blood than did the Control group (92.9 pg/ml vs. 40.2 pg/ml; p < 0.02). None of the animals had demonstrable mRNA for tumor necrosis factor in any of the tissues assayed. There were no demonstrable increases in ileal or cecal permeability for either the small or large molecular weight dextran in either alcohol group. Furthermore, there was no delay in the clearance of P. aeruginosa from the lung in the Subacute group, but these animals recruited fewer neutrophils into the airspaces in response to this challenge than did the Control animals. Thus, alcohol intoxication does not result in bacterial translocation from the gut in this model. Despite higher levels of portal venous endotoxin in the animals in the Subacute alcohol group, no adverse systemic consequences of this phenomenon could be demonstrated.
Alcohol Drinking↗
Liver-directed gene transfer in non-human primates.
To develop a primate model for liver-directed gene therapy, we studied several gene transfer vehicles and routes in eight rhesus monkeys (Macaca mulatta). For this purpose, we used first-generation, replication-deficient adenoviral vectors carrying the Escherichia coli lacZ gene (Ad.CMVlacZ) or a lacZ-containing plasmid (pCMV beta) with lipofectamine for transfection. The reporter gene construct was infused into either the portal vasculature, common bile duct, or saphenous vein. Adenovirus-mediated gene transfer via the portal vein resulted in expression of lacZ in over 70% of hepatocytes by days 3-7, but was accompanied by acute hepatitis. Adenovirus-mediated gene transfer via the common bile duct resulted in lacZ expression in less than 10% of hepatocytes and was accompanied by portal inflammation. The animals mounted a significant immune response, as demonstrated by adenoviral antigen-induced T-cell proliferation and production of neutralizing anti-adenovirus antibodies and antibodies to E. coli beta-galactosidase (beta-Gal). Activation of the immune response was associated with rapid decrease of the reporter gene by days 13-21. Lipofectamine-mediated gene transfer was inefficient, and no lacZ expression in the liver was detected. To limit the host immune response, 4 animals were immunosuppressed by cyclophosphamide/prednisone and then infused with the Ad.CMVlacZ via the portal vein or the saphenous vein. The monkeys showed sustained expression of lacZ for up to 35 days with no evidence of inflammation. The primates transduced via the saphenous vein showed a level of beta-Gal expression in the liver similar to that of the portal vein-infused animals. In conclusion, adenovirus-mediated gene transfer to non-human primate livers via the portal vein or saphenous vein is efficient, but it results in transient expression and is accompanied by an immune response to both vector and transgene products and acute hepatitis, whereas lipofectamine-mediated transfer is inefficient. Manipulation of the host immune response may expand potential applications of adenoviral vectors for liver-directed gene transfer.
Adenoviridae↗
Independent suppression of nitric oxide and TNF alpha in the lung of conscious rats by ethanol.
Tumor necrosis factor-alpha (TNF alpha) and nitric oxide (NO) mediate in part the microbicidal response of murine and rodent alveolar macrophages (AM) and recruited neutrophils (PMN) to airborne infections. Ethanol (ETOH) suppresses intrapulmonary TNF alpha and NO release and impairs pulmonary host defense mechanisms. We tested the concept that ETOH down-regulates NO by inhibiting production of TNF alpha. Male rats were given intratracheal (i.t.) saline (PBS), a polyclonal anti-TNF alpha antibody (TNFab) or nonimmune IgG (22 mg/kg, i.m.) 2 h before giving i.t. Escherichia coli endotoxin (LPS) to normal rats or rats pretreated with ETOM (5.5 g/kg, i.p.) 30 min before experimentation. AM and PMN were obtained from the bronchoalveolar lavage fluid (BAL) fluid of rats killed 2 and 4 h after administration of LPS. mRNA for inducible NO synthase (iNOS) and TNF alpha were measured in AM and PMN with competitor equalized RT-PCR techniques. The BAL fluid, AM, and PMN were assayed for TNF alpha and NO2-, and NO3- (RNI) with the L929 bioassay and chemiluminescence, respectively. TNFab abolished LPS-induced increases in TNF alpha but did not suppress the NO content of the BAL fluid or gene expression for iNOS by AM or PMN. ETOH suppressed LPS-induced increases in mRNA for iNOS, production of RNI, and BAL fluid TNF alpha but did not affect LPS-induced increases in mRNA for TNF alpha. ETOH-induced attenuation of LPS-induced up-regulation of the iNOS system did not differ in rats pretreated with TNFab or IgG. Thus, ETOH down-regulates iNOS gene expression and RNI production independent of its effects on TNF alpha. Acute ETOH administration suppresses iNOS at the level of transcription and TNF alpha at the level of translation or release of the peptide.
Amino Acid Oxidoreductases↗
Ethanol suppresses Mycobacteria tuberculosis-induced mRNA for nitric oxide synthase in alveolar macrophages, in vivo.
Acute ingestion of alcohol [ethanol (ETOH)] adversely affects the immunocompetence of both naive individuals as well as chronic alcohol abusers. An increased incidence and severity of tuberculosis is found in chronic alcohol abusers. Nitric oxide (NO) produced by alveolar macrophages (AMs) may play a role in the in vitro killing of Mycobacterium avium and Mycobacterium tuberculosis (MTB). Moreover, tumor necrosis factor-alpha (TNF-alpha) is believed to be a primary cytokine mediator of NO production by AMs. Recent studies from our laboratory demonstrated that ETOH suppressed endotoxin-induced increases in both TNF-alpha and NO in AMs, in vivo. We tested the postulate that acute ingestion of ETOH can interfere with mycobacteria-induced upregulation of the NO system in AMs, in vivo. We show that heat-killed M. avium complex (MAC) and human virulent MTB instilled into rat lungs rapidly increased mRNA for inducible NO synthase II (iNOS) of AMs in fluid obtained by bronchoalveolar lavage (BAL fluid). This was associated with production of reactive nitrogen intermediates [(RNIs); NO2- and NO3-] in BAL fluid, lung homogenate, and AMs in the absence of a significant increase in BAL fluid TNF-alpha. A single dose of ETOH (5.5 g/kg, ip) administered 30 min before intratracheal administration of MAC or MTB attenuated both MAC and MTB-induced increases in RNI in BAL fluid, lung, and AMs, and the increase in mRNA for iNOS. Thus, mycobacteria upregulate iNOS mRNA and enhance RNI production by AMs without any increase in the production of TNF-alpha. Moreover, ETOH attenuates mycobacteria-induced upregulation of mRNA for iNOS and RNI production in the absence of ETOH-mediated suppression of TNF. Speculatively, ETOH-mediated inhibition of the AM NO system may offer an explanation for the increased severity of mycobacterial infections in alcoholics.
Alcoholic Intoxication↗
In vivo administration of endotoxin and tumor necrosis factor-alpha produce different effects on constitutive and inducible nitric oxide synthase activity in rat neutrophils and aorta ex vivo.
Tumor necrosis factor-alpha (TNF-alpha) inhibits release of nitric oxide (NO) in vitro by stimulating the degradation of constitutive NO synthase (cNOS III) mRNA. However, TNF-alpha is believed to be the cytokine mediator of the hypotension and upregulation of inducible NO synthase (iNOS II) produced by gram-negative bacterial endotoxin (LPS). Some in vivo effects of TNF-alpha are opposite to those which occur in vitro. This study tested the hypothesis that in vivo administration of exogenous TNF-alpha and endogenously released TNF-alpha induce iNOS II activity and inhibit cNOS III activity, and thereby mediate the acute phase effects of LPS on blood pressure and the NO system in the rat. We show that LPS produces acute phase hypotension in ketamine anesthetized rats. The hypotension was associated with elevation of biologically active TNF-alpha in plasma, increased production of RNI (NO2- and NO3- anion) in rat neutrophils (PMN) and suppression of RNI production by A23187 (1 microM) stimulated thoracic aorta (RTA) ex vivo. TNA-alpha (10(6) U/ml, iv) did not produce acute phase hypotension but initially raised arterial blood pressure and heart rate (HR), did not increase RNI production by PMN, and inhibited RNI production by A23187 stimulated RTA ex vivo. Pretreatment of rats with the immunex monomeric soluble P75 receptor binding protein for TNF-alpha (TNFsr, 0.5 mg/kg, iv) 15 min prior to LPS administration decreased circulating TNF-alpha from 92,137 +/- 12,456 U/ml to undetectable levels as determined by the L929 bioassay. However, LPS-induced increases in RNI in PMN was enhanced and LPS-induced decreases in RNI production by RTA was inhibited by TNFsr. Thus, in vivo administration of TNF-alpha does not mimic the hemodynamic and NO-inducing effects of LPS. However, TNF-alpha mediates in part LPS-induced inhibition of RNI production by RTA. Thus, endogenous TNF-alpha is not required for LPS-induced acute phase hypotension or iNOS II activity. The importance of TNF-alpha in sepsis resides in systems other than iNOSII and blood pressure.
Amino Acid Oxidoreductases↗
Rapid induction of mRNA for nitric oxide synthase II in rat alveolar macrophages by intratracheal administration of Mycobacterium tuberculosis and Mycobacterium avium.
Mycobacterium avium complex (MAC) organisms are among the most common bacterial cause of disseminated infection in patients with acquired immune deficiency syndrome (AIDS). An increase in the incidence of virulent Mycobacterium tuberculosis (MTB) is also occurring throughout the world. In vitro data suggest that nitric oxide (NO) may be important in restricting the growth of MAC. However, the ability of MTB to stimulate NO production and the susceptibility of MTB to the bactericidal activity of NO produced by murine alveolar macrophages (AM) is controversial. This study tested the hypothesis that in vivo administration of heat-killed MAC (strain 100 and 101) and human virulent MTB (strain F1) to rats stimulated NO production by rat AM, ex vivo. We show that heat-killed MTB instilled into rat lungs rapidly induced mRNA for NO synthase (iNOS) II in AM obtained by bronchoalveolar lavage (BAL). In contrast, expression of AM iNOS mRNA was only found in 40% of the rats given MAC. Moreover, the change in iNOS mRNA in the AM obtained from rats given MTB and MAC correlated with the production of the reactive nitrogen intermediates (RNI) NO2- and NO3- in BAL fluid, lung homogenate, and the spontaneous generation of RNI by isolated AM ex vivo and occurred without measurable increases in BAL fluid tumor necrosis factor-alpha (TNF-alpha). L-NG-monomethylarginine (50 mg/kg, ip) given 30 min before MAC or MTB attenuated the increase in RNI in lung homogenates and BAL fluid. This is the first demonstration that in vivo exposure to MTB results in rapid upregulation of gene expression for iNOS which is associated with functional RNI production by rat AM. These results show that MTB human virulent strain 1 has the ability to rapidly upregulate iNOS mRNA in AM. If human AM generate NO from L-arginine by either iNOS or other NADPH oxidases then NO may play a role in the overall host-defense response of the lung to MAC and MTB.
Amino Acid Oxidoreductases↗
Pathophysiology of pneumonia.
The care and management of the pneumonia patient are formidable challenges to the physician. As long as the basic underlying host defense defects in these patients remain elusive, the clinician's approach will remain symptomatic and empirical. Further knowledge of the underlying pathophysiology of pneumonia will undoubtedly provide innovative approaches to both the prevention and the early and effective treatment of this infection. Clearly, the development of a multimodal approach, including components of immune modulation and immune restoration, is needed to improve the multiple defects in the host defense system; however, the normal host defense system operates in a delicate balance. Efforts to stimulate the immune system nonselectively may prove to be as deleterious to the patient as are the negative effects of their immunocompromised state.
Antibody Formation↗
Prolonged and effective blockade of tumor necrosis factor activity through adenovirus-mediated gene transfer.
A chimeric protein capable of binding and neutralizing tumor necrosis factor (TNF) and lymphotoxin was expressed in mice transduced with a replication-incompetent adenoviral vector into which a TNF inhibitor gene had been engineered. Within 3 days following the injection of 10(9) infectious particles, the TNF inhibitor concentration exceeded 1 mg/ml of plasma; this level of expression was maintained for at least 4 weeks, and detectable TNF inhibitory activity was measured 6 weeks after injection of the recombinant virus. Introduction of the artificial gene produced a phenotypic effect comparable to homozygous deletion of the 55-kDa TNF receptor, in that animals were rendered highly susceptible to infection by Listeria monocytogenes, whereas control animals receiving a replication-incompetent virus coding for beta-galactosidase were capable of resisting Listeria challenge. Adenovirus-mediated transfer of a gene encoding a TNF inhibitor offers a practical means of imposing effective, long-term blockade of TNF activity in vivo for investigational and therapeutic purposes.
Adenoviridae↗