scholarly journals Development of a Targeted Gene Vector Platform Based on Simian Adenovirus Serotype 24

2010 ◽  
Vol 84 (19) ◽  
pp. 10087-10101 ◽  
Author(s):  
Natalya Belousova ◽  
Galina Mikheeva ◽  
Chiyi Xiong ◽  
Suren Soghomonian ◽  
Daniel Young ◽  
...  

ABSTRACT Efforts to develop adenovirus vectors suitable for genetic interventions in humans have identified three major limitations of the most frequently used vector prototype, human adenovirus serotype 5 (Ad5). These limitations—widespread preexisting anti-Ad5 immunity in humans, the high rate of transduction of normal nontarget tissues, and the lack of target-specific gene delivery—justify the exploration of other Ad serotypes as vector prototypes. In this paper, we describe the development of an alternative vector platform using simian Ad serotype 24 (sAd24). We found that sAd24 virions formed unstable complexes with blood coagulation factor X and, because of that, transduced the liver and other organs at low levels when administered intravenously. The overall pattern of biodistribution of sAd24 particles was similar, however, to that of Ad5, and the intravenously injected sAd24 was cleared by Kupffer cells, leading to their depletion. We modified the virus's fiber protein to design a Her2-specific derivative of sAd24 capable of infecting target human tumor cells in vitro. In the presence of neutralizing anti-Ad5 antibodies, Her2-mediated infection with targeted sAd24 compared favorably to that with the Ad5-derived vector. When used to target Her2-expressing tumors in animals, this fiber-modified vector achieved a higher level of gene transfer to metastasis-containing murine lungs than to tumor-free lungs. In aggregate, these studies provide important insights into sAd24 biology, identify its advantages and limitations as a vector prototype, and are thus essential for further development of an sAd24-based gene delivery platform.

2008 ◽  
Vol 83 (1) ◽  
pp. 479-483 ◽  
Author(s):  
Alan L. Parker ◽  
Simon N. Waddington ◽  
Suzanne M. K. Buckley ◽  
Jerome Custers ◽  
Menzo J. E. Havenga ◽  
...  

ABSTRACT The deployment of adenovirus serotype 5 (Ad5)-based vectors is hampered by preexisting immunity. When such vectors are delivered intravenously, hepatocyte transduction is mediated by the hexon-coagulation factor X (FX) interaction. Here, we demonstrate that human sera efficiently block FX-mediated cellular binding and transduction of Ad5-based vectors in vitro. Neutralizing activity correlated well with the ability to inhibit Ad5-mediated liver transduction, suggesting that prescreening patient sera in this manner accurately predicts the efficacy of Ad5-based gene therapies. Neutralization in vitro can be partially bypassed by pseudotyping with Ad45 fiber protein, indicating that a proportion of neutralizing antibodies are directed against the Ad5 fiber.


2014 ◽  
Vol 89 (5) ◽  
pp. 2884-2891 ◽  
Author(s):  
Karsten Eichholz ◽  
Franck J. D. Mennechet ◽  
Eric J. Kremer

ABSTRACTOne of the first lines of host defense against many viruses in vertebrates is the innate immune system, which detects pathogen-associated molecular patterns (PAMPs) using pathogen recognition receptors (PRR). The dynamic interactions between pathogens and hosts create, in some cases, species-specific relationships. Recently, it was shown that murine factor X (mFX)-armored human adenovirus (HAd) stimulated a mFX-Toll-like receptor 4 (TLR4)-associated response in mouse macrophagesin vitroandin vivo. Given the importance of studies using animals to better understand host-pathogen interactions, we asked if human FX (hFX)-armored HAd type 5 (HAd5) was capable of activating innate immune sensors in primary human mononuclear phagocytes. To this end, we assayed human mononuclear phagocytes for their ability to be stimulated by hFX-armored HAd5 via a TLR/NF-κB pathway, in particular, a TLR4 pathway. In our hands, we found no significant interaction, activation, or maturation of human mononuclear phagocytes caused by the presence of hFX-armored HAd5.IMPORTANCEAnimals, and mice in particular, are often used as informative and powerful surrogates for how pathogens interact with natural host systems. When possible, extended and targeted studies in the natural host can then be performed. Our data will help us understand the differences in preclinical testing in mice and clinical use in humans in order to improve treatment for HAd diseases and Ad vector effectiveness.


2009 ◽  
Vol 17 (10) ◽  
pp. 1683-1691 ◽  
Author(s):  
Jenny A Greig ◽  
Suzanne MK Buckley ◽  
Simon N Waddington ◽  
Alan L Parker ◽  
David Bhella ◽  
...  

2015 ◽  
Vol 11 (2) ◽  
pp. e1004673 ◽  
Author(s):  
Jiangtao Ma ◽  
Margaret R. Duffy ◽  
Lin Deng ◽  
Rachel S. Dakin ◽  
Taco Uil ◽  
...  

1987 ◽  
Author(s):  
B JUDE ◽  
A WATEL ◽  
D FONTAINE ◽  
P FONTAINE ◽  
A COSSON

Hypercoagulability is one of the possible factors reported in genesis or aggravation of vascular complications in diabetes mellitus. We therefore examined procoagulant activity (PCA) of disrupted monocytes frcm 26 patients with Type I diabetes and 6 with Type II, versus 32 control subjects (male/ female ratio = 1 in each group).Diabetes monocytes exhibited a slight but detectable PCA before any incubation or in vitro stimulation, whereas control monocytes did not. Data obtained with coagulation factor deficient plasmas or phospholipase C indicated that PCA was tissue factor (TF) alone in 22 cases and TF associated with a significant amount of factor VII/VIIa activity in 10 cases.Incubation in serum free medium led to significant raise of PCA in diabetes cells when stimulated with endotoxin or not, and in control cells only after stimulation. Furthermore, PCA appeared earlier in diabetes monocytes than in control ones, (4 hours, versus 20 hours). PCA frcm control cells was FT-like. PCA frcm diabetes cells was FT-like when no VII/VIIa activity was present on non-stimulated cells, and prothrombinase-like when VII/VIIa activity was early associated with the cells. In the latter case, trace amounts of factor X activity were also detectable. Whether factor VII and factor X activities were of plasmatic origin and associated to the cells, or synthesized in vitro by the cells remains unclear. The characteristics of PCA were net correlated with clinical features (age, diabetic complications) nor with the type of diabetes.Our data suggest that in diabetes patients, monocytes exhibit an increased PCA, possibly corresponding to a baseline stimulation, or at least a higher responsiveness to undergoing stimuli in vitro.


Blood ◽  
2020 ◽  
Author(s):  
Georg Obermayer ◽  
Taras Afonyushkin ◽  
Laura Goederle ◽  
Florian Puhm ◽  
Waltraud C. Schrottmaier ◽  
...  

Thrombosis and the complications associated with it are a major cause of morbidity and mortality worldwide. Microvesicles (MVs), a class of extracellular vesicles, are increasingly recognized as mediators of coagulation and biomarkers of thrombotic risk. Thus, identifying factors targeting MV-driven coagulation may help in the development of novel antithrombotic treatments. We have previously identified a subset of circulating MVs that is characterized by the presence of oxidation-specific epitopes and bound by natural IgM antibodies targeting these structures. Here, we investigated whether natural IgM antibodies, which are known to have important anti-inflammatory house-keeping functions, inhibit the procoagulatory properties of MVs. We found that the extent of plasma coagulation is inversely associated with the levels of both free and MV-bound endogenous IgM. Moreover, the oxidation epitope-specific natural IgM antibody LR04, which recognizes malondialdehyde adducts, reduced MV-dependent plasmatic coagulation and whole blood clotting without affecting thrombocyte aggregation. Intravenous injection of LR04 protected mice from MV-induced pulmonary thrombosis. Of note, LR04 competed the binding of coagulation factor X/Xa to MVs, providing a mechanistic explanation for its anticoagulatory effect. Thus, our data identify natural IgM antibodies as hitherto unknown modulators of MV-induced coagulation in vitro and in vivo and their prognostic and therapeutic potential in the management of thrombosis.


2006 ◽  
Vol 6 (9) ◽  
pp. 2860-2866 ◽  
Author(s):  
Dongwon Lee ◽  
Richard Lockey ◽  
Shyam Mohapatra

Chitosan-mediated gene delivery has gained an increasing interest due to its ability to treat cancers and genetic diseases. However, low transfection efficiency and lack of target specificity limit its application for gene and drug delivery. In the present work, folic acid was covalently conjugated to chitosan as a targeting ligand in an attempt to specifically deliver DNA to folate receptor-overexpressing cancer cells. Folic acid-conjugated chitosan (FACN) was successfully synthesized and characterized by 1H-NMR and is biocompatible. In vitro gene transfer potential of FACN was evaluated in human epithelial ovarian cancer OV2008 cells and human breast cancer MCF-7 cells. FACN at a weight ratio of 10 : 1 exhibited significantly (< 0.01) enhanced gene transfer potential in folate receptor-overexpressing cancer cells as compared to unmodified chitosan. Transfection of FACN/pDNA nanocomplexes is competitively inhibited by free folic acid, suggesting the specific gene delivery of FACN/pDNA nanocomplexes is achieved through folate receptor-mediated endocytosis. Taken together, these results demonstrate that FACN provides a promising carrier for cancer gene therapy.


Blood ◽  
2010 ◽  
Vol 116 (15) ◽  
pp. 2656-2664 ◽  
Author(s):  
Raul Alba ◽  
Angela C. Bradshaw ◽  
Lynda Coughlan ◽  
Laura Denby ◽  
Robert A. McDonald ◽  
...  

AbstractA major limitation for adenoviral transduction in vivo is the profound liver tropism of adenovirus type 5 (Ad5). Recently, we demonstrated that coagulation factor X (FX) binds to Ad5-hexon protein at high affinity to mediate hepatocyte transduction after intravascular delivery. We developed novel genetically FX-binding ablated Ad5 vectors with lower liver transduction. Here, we demonstrate that FX-binding ablated Ad5 predominantly localize to the liver and spleen 1 hour after injection; however, they had highly reduced liver transduction in both control and macrophage-depleted mice compared with Ad5. At high doses in macrophage-depleted mice, FX-binding ablated vectors transduced the spleen more efficiently than Ad5. Immunohistochemical studies demonstrated transgene colocalization with CD11c+, ER-TR7+, and MAdCAM-1+ cells in the splenic marginal zone. Systemic inflammatory profiles were broadly similar between FX-binding ablated Ad5 and Ad5 at low and intermediate doses, although higher levels of several inflammatory proteins were observed at the highest dose of FX-binding ablated Ad5. Subsequently, we generated a FX-binding ablated virus containing a high affinity Ad35 fiber that mediated a significant improvement in lung/liver ratio in macrophage-depleted CD46+ mice compared with controls. Therefore, this study documents the biodistribution and reports the retargeting capacity of FX binding-ablated Ad5 vectors in vitro and in vivo.


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