PERSPECTIVES
Modelling the Virtual Physiological Human

The second half of the twentieth century can be regarded as the era of reductionism in biology, when, driven by

revolutions in molecular biology and genomics, the dominant paradigm saw biology as the sum of its parts: the

genes and proteins that make up each organism. Most biologists, however, now recognize that an integrative

approach – an understanding of how these parts work together in a complex entity – is as important as a reductionist

one. The relatively new discipline of systems biology combines this philosophy with an integration of

experimental biology with computational biology. One of the most ambitious goals of systems biology is that of

modeling the entire human physiology. Human body can be broken down into a series of interlocking organs and

systems, with one of the most tractable to model being the heart. Simple mathematical models of cardiac ion

channel action have developed over half a century into complex simulations that are being used successfully in

drug discovery. Integrating models together, however, requires close international collaboration. Under Framework

Six, the European Commission funded a few collaborative projects in human systems biology including

ImmunoGrid, which set out, perhaps over-ambitiously, to model the immune system. Under Framework Seven,

over €200 M has been channeled into research projects and networks under the umbrella of the Virtual Physiological

Human. Projects funded under this initiative cover a large range of systems and disease states, with

the cardio-vascular system and cancer dominating the first tranche of fifteen. This initiative is poised to further

develop under the next framework programme (Horizon 2020), which will run for seven years from 2014.