Suppression of the Insulin Receptors in Adult Schistosoma japonicum Impacts on Parasite Growth and Development: Further Evidence of Vaccine Potential

To further investigate the importance of insulin signaling in the growth, development, sexual maturation and egg production of adult schistosomes, we have focused attention on the insulin receptors (SjIRs) of Schistosoma japonicum, which we have previously cloned and partially characterised. We now show, by Biolayer Interferometry, that human insulin can bind the L1 subdomain (insulin binding domain) of recombinant (r)SjIR1 and rSjIR2 (designated SjLD1 and SjLD2) produced using the Drosophila S2 protein expression system. We have then used RNA interference (RNAi) to knock down the expression of the SjIRs in adult S. japonicum in vitro and show that, in addition to their reduced transcription, the transcript levels of other important downstream genes within the insulin pathway, associated with glucose metabolism and schistosome fecundity, were also impacted substantially. Further, a significant decrease in glucose uptake was observed in the SjIR-knockdown worms compared with luciferase controls. In vaccine/challenge experiments, we found that rSjLD1 and rSjLD2 depressed female growth, intestinal granuloma density and faecal egg production in S. japonicum in mice presented with a low dose challenge infection. These data re-emphasize the potential of the SjIRs as veterinary transmission blocking vaccine candidates against zoonotic schistosomiasis japonica in China and the Philippines.

Perceptions of the common good in planning

There has been plenty of debate in the academic literature about the nature of the common good or public interest in planning. There is a recognition that the idea is one that is extremely difficult to isolate in practical terms; nevertheless, scholars insist that the idea ‘…remains the pivot around which debates about the nature of planning and its purposes turn’ (Campbell & Marshall, 2002, 163–64). At the point of first principles, these debates have broached political theories of the state and even philosophies of science that inform critiques of rationality, social justice and power. In the planning arena specifically, much of the scholarship has tended to focus on theorising the move from a rational comprehensive planning system in the 1960s and 1970s, to one that is now dominated by deliberative democracy in the form of collaborative planning. In theoretical terms, this debate has been framed by a movement from what are perceived as objective and elitist notions of planning practice and decision-making to ones that are considered (by some) to be ‘inter-subjective’ and non-elitist. Yet despite significant conceptual debate, only a small number of empirical studies have tackled the issue by investigating notions of the common good from the perspective of planning practitioners. What do practitioners understand by the idea of the common good in planning? Do they actively consider it when making planning decisions? Do governance/institutional barriers exist to pursuing the common good in planning? In this paper, these sorts of questions are addressed using the case of Ireland. The methodology consists of a series of semi-structured qualitative interviews with 20 urban planners working across four planning authorities within the Greater Dublin Area, Ireland. The findings show that the most frequently cited definition of the common good is balancing different competing interests and avoiding/minimising the negative effects of development. The results show that practitioner views of the common good are far removed from the lofty ideals of planning theory and reflect the ideological shift of planners within an institution that has been heavily neoliberalised since the 1970s.