Cell and gene therapies at the forefront of innovative medical care: Implications for South Africa

The fields of cell and gene therapy are moving rapidly towards providing  innovative cures for incurable diseases. A current and highly topical  example is immunotherapies involving T-cells that express chimeric antigen receptors (CAR T-cells), which have shown promise in the treatment of leukaemia and lymphoma. These new medicines are indicative of the changes we can anticipate in the practice of medicine in the near future. Despite their promise, they pose challenges for introduction into the healthcare sector in South Africa (SA), including: (i) that they are  technologically demanding and their manufacture is resource intensive; (ii) that the regulatory system is underdeveloped and likely to be challenged by ethical, legal and social requirements that accompany these new therapies; and (iii) that costs are likely to be prohibitive, at least initially, and before economies of scale take effect. Investment should be made into finding novel and innovative ways to introduce these therapies into SA sooner rather than later to ensure that SA patients are not excluded from these exciting new opportunitie

Thrombospondin-1 is downregulated by anoxia and suppresses tumorigenicity of human glioblastoma cells.

Angiogenesis, the sprouting of new capillaries from preexisting blood vessels, results from a disruption of the balance between stimulatory and inhibitory factors. Here, we show that anoxia reduces expression of thrombospondin-1 (TSP-1), a natural inhibitor of angiogenesis, in glioblastoma cells. This suggests that reduced oxygen tension can promote angiogenesis not only by stimulating the production of inducers, such as vascular endothelial growth factor, but also by reducing the production of inhibitors. This downregulation may significantly contribute to glioblastoma development, since we show that an increase in TSP-1 expression is sufficient to strongly suppress glioblastoma cell tumorigenicity in vivo

The prototypes of tobacco users scale (Potus) for cigarette smoking and e-cigarette use: Development and validation

Endorsing prototypes of cigarette smokers predicts cigarette smoking, but less is known about prototypes of users of other tobacco products. Our study sought to establish the reliability and validity of a measure of prototypes of smokers and e-cigarette users. Participants were from a national survey of smokers and non-smokers (n = 1414), a randomized clinical trial (RCT) of adult smokers (n = 2149), and adolescent children of adults in the trial (n = 112). The Prototypes of Tobacco Users Scale (POTUS) has four positive adjectives (cool, sexy, smart, and healthy) and four negative adjectives (disgusting, unattractive, immature, and inconsiderate) describing cigarette smokers and e-cigarette users. Confirmatory factor analyses identified a two-factor solution. The POTUS demonstrated strong internal consistency reliability in all three samples (median α = 0.85) and good test–retest reliability among adults in the RCT (median r = 0.61, 1–4 weeks follow-up). In the RCT, smokers more often agreed with negative prototypes for smokers than for e-cigarette users (mean = 2.03 vs. 1.67, p < 0.05); negative prototypes at baseline were also associated with more forgoing of cigarettes and making a quit attempt at the end of the trial (Week 4 follow-up). The POTUS may be useful to public health researchers seeking to design interventions that reduce tobacco initiation or cessation through the manipulation of tobacco user prototypes

Evaluation of TickGARD(PLUS), a novel vaccine against Boophilus microplus, in lactating Holstein-Friesian cows

The effects of vaccination with the Bm 86 vaccine TickGARDPLUS against infestation with cattle tick (Boophilus microplus) and of holding cattle on a feedpad until 09:00 hours after the morning milking was tested on 40 mid lactation Holstein cattle using a factorial design. Vaccination resulted in a 56% reduction in tick numbers in the field over one generation, and a 72% reduction in laboratory measures of the reproductive efficiency of ticks. The liveweight gain of vaccinated cattle over 27 weeks was 18.6 kg higher than that of controls, and vaccinated cattle tended to have lower somatic cell count in milk (SCC). There were no other significant differences in measures of production. Cattle kept on the feedpad after the morning milking carried 26% more ticks than those returned immediately to their paddocks

Endothelial cells of the microvasculature express epidermal fatty acid-binding protein (E-FABP)

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Tetracycline-regulated expression of VEGF-A in beta cells induces angiogenesis: improvement of engraftment following transplantation.

Early revascularization of pancreatic islet cells after transplantation is crucial for engraftment, and it has been suggested that vascular endothelial growth factor-A (VEGF-A) plays a significant role in this process. Although VEGF gene therapy can improve angiogenesis, uncontrolled VEGF secretion can lead to vascular tumor formation. Here we have explored the role of temporal VEGF expression, controlled by a tetracycline (TC)-regulated promoter, on revascularization and engraftment of genetically modified beta cells following transplantation. To this end, we modified the CDM3D beta cell line using a lentiviral vector to promote secretion of VEGF-A either in a TC-regulated (TET cells) or a constitutive (PGK cells) manner. VEGF secretion, angiogenesis, cell proliferation, and stimulated insulin secretion were assessed in vitro. VEGF secretion was increased in TET and PGK cells, and VEGF delivery resulted in angiogenesis, whereas addition of TC inhibited these processes. Insulin secretion by the three cell types was similar. We used a syngeneic mouse model of transplantation to assess the effects of this controlled VEGF expression in vivo. Time to normoglycemia, intraperitoneal glucose tolerance test, graft vascular density, and cellular mass were evaluated. Increased expression of VEGF resulted in significantly better revascularization and engraftment after transplantation when compared to control cells. In vivo, there was a significant increase in vascular density in grafted TET and PGK cells versus control cells. Moreover, the time for diabetic mice to return to normoglycemia and the stimulated plasma glucose clearance were also significantly accelerated in mice transplanted with TET and PGK cells when compared to control cells. VEGF was only needed during the first 2-3 weeks after transplantation; when removed, normoglycemia and graft vascularization were maintained. TC-treated mice grafted with TC-treated cells failed to restore normoglycemia. This approach allowed us to switch off VEGF secretion when the desired effects had been achieved. TC-regulated temporal expression of VEGF using a gene therapy approach presents a novel way to improve early revascularization and engraftment after islet cell transplantation