Promising Bio-hybrid Kidney Could Make Dialysis Unnecessary

Scientists have designed a new bio-hybrid kidney containing microchips that mimic functions of the kidney, with a potential to remove the need for a dialysis.

Bio-hybrid chip mimics kidney functions
The silicone chip is powered by the heart
Removes waste, salt and water
Could probably replace the need for dialysis in the future

William H Fissell IV from Vanderbilt University Medical Center has designed a microchip that mimics the functions of a kidney and is believed to remove waste from the body, along with salt and water. This, researchers believe, will eliminate the need for a dialysis.

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‘The bio-hybrid kidney could potentially provide a less cumbersome option for kidney patients who need dialysis.’

This artificial kidney project began many years ago and gained importance in 2010 as news of the invention spread, with an Indian among the research group, Dr Shuvo Roy.

In September 2015, the current project on artificial kidney transplantation into humans was to be included in the FDA's new Expedited Access Pathway program to speed development, evaluation, and review of medical devices which could be used to support fighting life-threatening or irreversibly debilitating diseases.

Burden of Kidney Disease

Approximately, 30 million Americans suffer from chronic kidney disease
In 2010, six million people worldwide were estimated to be requiring renal replacement
A study conducted in Chennai, India showed that 8600 per million people suffered from kidney disease

Importance of Dialysis

In chronic and end stage kidney failure, doctors suggest dialysis as it aids in -

Removing waste, salt and water from the system
Controlling the concentration of sodium, bicarbonate and potassium
Maintaining blood pressure

Patients who are very old may be unable to cope with a kidney transplant. Finding the right donor for kidney replacement is also a difficult task. Therefore, patients need to resort to dialysis while some require dialysis till the end of their life.

Some patients find the process of dialysis painful when the needles are inserted into the grafts. Moreover, the procedure can be daunting for an elderly patient who is unable to bear the pain. The bio-hybrid kidney, designed by William H Fissell IV and colleagues including Shuvo Roy, if found to replace the need for dialysis, will be a boon for such patients.

Mechanism of Action

The device consists of approximately 15 microchips, stacked one on top of another. Lab-grown kidney cells will then grow on and around these microchips. This bio-hybrid device will then emulate the functions of the kidney and know the good from the bad, like Santa Claus, according to Fissell. Nutrients required by the body are absorbed by the device and the waste discarded.

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Highlights of the Device and Future Work:

Waste is discarded and nutrients absorbed
Scientists are trying to build it to the size of a soda can
It is placed beyond the extent of the body’s immune system. Therefore, there is no rejection.
The patient’s heart and blood flow aid in operating the device.
Researchers are testing the device to identify areas that are at a risk of clotting.

Laboratory Experiments Conducted With the Device:

Mechanical stability was tested by exposure to -

High flows - 200ml/min
Pressure - 1,448mmHg

Diffusive clearance in an albumin solution and whole blood and the flow rate was 25ml/min.
Blood was driven across the membrane by arterial venous pressure without clotting.

The lab studies need further analysis, but the scientists hope to begin patient testing by the end of 2017.

The bio-hybrid kidney is expected to alleviate the pain associated with dialysis. While there are plenty of hopes pinned on the current prototype, it will be interesting to watch how this device is finally designed and the benefits it would bring.

Quiz on Dialysis
Dialysis is a common procedure performed in patients with kidney failure, especially those who are awaiting kidney transplantation. Test your knowledge on dialysis by taking this quiz.

If found to be successful, it will -

Reduce the pain associated with dialysis
Lower economic strain
Lessen the need for a kidney donor and risk of organ rejection

References:

1. http://www.niddk.nih.gov/health-information/health-statistics/Pages/kidney-disease-statistics-united-states.aspx#3

Dialysis - Hemodialysis, Peritoneal Dialysis and Role of Diet and Drugs
Dialysis is an artificial process for removing excess water and waste from the blood. Hemodialysis and peritoneal dialysis are the types of dialysis.

2. https://ndt.oxfordjournals.org/content/21/1/232.full

3. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2845186/

4. https://www.kidney.org/atoz/content/dialysisinfo

5. Kim S, Heller J, Iqbal Z, Kant R, Kim EJ, Durack J, Saeed M, Do L, Hetts S, Wilson M, Brakeman P, Fissell WH, Roy S. “Preliminary Diffusive Clearance of Silicon Nanopore Membranes in a Parallel Plate Configuration for Renal Replacement Therapy.” ASAIO J. 2015 Dec 21

Source-Medindia