In-vitro vs in-situ tissue engineering. What are the differences?

There is a lot of hype around in-vitro tissue engineering, because ‘growing an organ in a lab’ appears futuristic. To many people, it seems like an exciting concept.

Growing something outside of the body, then putting it back inside to ultimately improve your health and change your life – almost seems unreal. But it is becoming reality.

However, in many cases in-vitro tissue engineering is also expensive, time-consuming and under-developed. It takes time to grow cells and tissue; and there is no guarantee the cells and tissues grown are viable and not mutated.

At Osteopore, we are looking at a more direct way of applying tissue engineering concepts to achieve clinical impact. In-situ tissue engineering is a more cost-effective and reproducible alternative to in-vitro tissue engineering because of quality control and we can consistently repeat the same desired results.

With in-situ tissue engineering, we are looking at medical products that interface with blood, blood vessels and cells – working in proposed harmony with how your body already functions.

It essentially harnesses the native regenerative potential of the body to regenerate tissue, as opposed to creating it wholesale in an in-vitro environment.

Rather than implanting cells into a body from an external source, in-situ tissue engineering looks to recruit endogenous stem cells (cells created within a living organism) to the site of an injury by using biomaterial with 3D microarchitecture and/or growth-factor-based cues to enhance healing.

When it comes to in-situ tissue engineering, any construct that is implanted into the body is not a fully-functional, full-size replacement of the lost tissue – rather, the constructs look to grow with and enhance the pre-existing regenerative capabilities of the human body.

On the other hand, in-vitro tissue engineering creates functional tissue that can be used to replace tissue in the body and has a number of practical uses in terms of studying biological processes – leading to significant advances in the area of regenerative medicine.

In-vitro tissue engineering aims to recreate tissue structures that are functionally mature in a bioreactor, which creates a template for how that tissue will behave inside a living organism.

But in-vitro tissue also faces a number of concerns before successful standard-of-care implementation in humans. Finding enough cells that are acceptable to the immune system is not simple, and there are also challenges in terms of the availability and scaling-up capability of in-vitro tissue engineering. Cost-effectiveness, preservation and handling also present problems.

A recent study by the Biomedical Engineering Society www.bmes.org looked closely at the differences between in-vitro and in-situ tissue engineering, finding in-situ tissue engineering represents a promising new avenue of regenerative therapy research.

In-situ tissue engineering represents the future for not only Osteopore but potentially the medical devices industry as a whole because: it is less onerous from a regulatory standpoint; it is a more scalable and cost-effective solution; it is a more familiar process to the surgical community; and it has long-term, lasting impacts.