In vivo noninvasive visualization of retinal perfusion dysfunction in murine cerebral malaria by camera-phone laser speckle imaging.

Cerebral malaria (CM) is a severe complication of Plasmodium falciparum infection associated with impaired cerebral blood flow. Visualization of the eye vasculature, which is embryologically derived from that of the brain, is used clinically to diagnose the syndrome. Here, we introduce camera-phone laser speckle imaging as a new tool for in vivo, noncontact two-dimensional mapping of blood flow dynamics in the experimental cerebral malaria (ECM) murine model of Plasmodium berghei ANKA. In a longitudinal study, we show that the camera-phone imager can detect an overall decrease in the retinal blood-flow-speed (BFS) as ECM develops in P. berghei ANKA infected mice, with no similar change observed in uninfected control mice or mice infected with a non-ECM inducing strain (P. berghei NK65). Furthermore, by analyzing relative alterations in the BFS of individual retinal vessels during the progression of ECM, we illustrate the strength of our imager in identifying different BFS-change heterogeneities in the retinas of ECM and uninfected mice. The technique creates new possibilities for objective investigations into the diagnosis and pathogenesis of CM noninvasively through the eye. The camera-phone laser speckle imager along with measured spatial blood perfusion maps of the retina of a mouse infected with P. berghei ANKA-a fatal ECM model-on different days during the progression of the infection (top, day 3 after infection; middle, day 5 after infection; and bottom, day 7 after infection).

Safety of direct cardiac administration of AdVEGF-All6A+, a replication-deficient adenovirus vector cDNA/genomic hybrid expressing all three major isoforms of human vascular endothelial growth factor, to the ischemic myocardium of rats.

Abstract Coronary artery disease (CAD), a leading cause of mortality, is a chronic disease in which blood flow to the myocardium is obstructed, leading to ischemia. Although coronary artery stenting and surgical bypass are successful with localized coronary lesions, patients with diffuse CAD have only pharmacologic options. In a mouse ischemic hind-limb model, AdVEGF-All6A+, an Ad5 vector expressing the cDNA/genomic hybrid of the vascular endothelial growth factor (VEGF) gene (expressing isoforms, 121, 165, and 189) mediated recovery of blood flow at a dose of two logs less than that required with a single isoform. The objective of the current study was to ascertain the safety profile of good manufacturing practice (GMP)-grade AdVEGF-All6A+ in the adult rat ischemic heart model in support of a clinical study to treat humans with diffuse CAD. AdVEGF-All6A+ (10(5), 10(6), or 10(7) particle units), a control vector (AdNull, 10(7) particle units) with no translatable expression cassette and a vehicle sham control (phosphate buffered saline [PBS]) were administered separately to the left ventricle of rats immediately following acute coronary artery ligation to initiate myocardial infarction (MI), designed to evoke an extreme ischemic myocardium in cohorts (n=5 males; n=5 females), with sacrifice at 5, 14, or 30 days. Six cohorts received no ligation but were administered AdVEGF-All6A+ vector or PBS with sacrifice at 30 or 365 days. Although there were surgical-related abnormalities among the groups, blinded evaluation of gross and histopathology, complete blood count, and serum chemistry found no significant differences between control- and vector-treated groups and no adverse effects could be attributed to AdVEGF-All6A+. No changes in serum troponin-I levels persisted beyond those associated with the MI. Gross pathology and histopathology of all major organs showed no AdVEGF-All6A+-related changes. Overall, this safety profile suggests that AdVEGF-All6A+ or AdNull administration to the myocardium meets the criteria to proceed to clinical trial.

Ablation of tumor-derived stem cells transplanted to the central nervous system by genetic modification of embryonic stem cells with a suicide gene.

Embryonic stem cell (ESC)-based therapies open new possibilities as regenerative medicine for the treatment of human disease, but the presence of small numbers of undifferentiated ESCs within the transplant could lead to the development of tumors. The safety of ESC transplants would be enhanced if uncontrolled cell growth could be suppressed, using external stimuli. A lentiviral vector carrying the herpes simplex virus thymidine kinase (HSVtk) and green fluorescent protein (GFP) genes was used to genetically modify murine ESCs (HSVtk+GFP+ ESCs). In the presence of ganciclovir (GCV), 100% of HSVtk+GFP+ ESCs were killed in vitro, and 100% of flank tumors derived from HSVtk+GFP+ ESCs were eliminated. When CNS tumors were produced by the HSVtk+GFP+ ESCs, the tumor mass was completely eliminated on GCV treatment for 1 week. After GCV treatment for 3 weeks, histologic analysis showed no residual tumor cells and TaqMan realtime polymerase chain reaction analysis showed no genomic HSVtk copies or HSVtk mRNA. These data demonstrate that it is possible to use ex vivo gene transfer to modify ESCs with conditional genetic elements that can be activated in vivo to control undifferentiated ESC outgrowth and to eliminate transduced ESCs that have escaped growth control after ESC-mediated therapy to the CNS.