Organovo is the bioprinting startup whose investors include the Methuselah Foundation: "Organovo has been generating enough revenue from a series of new partnerships that [the company] put off an expected Series A venture round. ... the company has raised just over $2 million from private investors to develop 'bio-printing' technology that operates much like an inkjet printer. Instead of laying down ink, however, Organovo's bio-printer lays down a pattern of cultured cells and a jello-like hydrogel that supports the cells in a 3-D structure. In this way, Organovo already has been able to grow bio-engineered blood vessels, and to lay more ambitious plans to create kidneys, livers, and other vital organs in the same way. ... the work is still highly experimental, so getting regulatory approval to graft a bio-engineered blood vessel in a living patient will take years. In the meantime, [Organovo] found a burgeoning market among pharmaceutical companies by [creating] 3-dimensional 'constructs' of diseased or dysfunctional human cells that can be used as models for testing new drugs. Creating a 3-D matrix of cells enables each cell to interact with adjoining cells, so they react to drug compounds much as they would in the body. ... one of the pharmaceutical partnerships is with Pfizer to create 3-D constructs for drug discovery in two therapeutic areas. Organovo also is in talks with several additional partners ... One of the things that's been good about the past six months is that the promise of our technology is holding true. The constructs we're creating robustly build [blood vessels] with collagen, so the blood vessel grows stronger over time. The next challenge is getting to greater and greater vascularization of the construct. The emerging story is going to be, 'Who can make thicker tissues with more blood vessels inside?'"