University of Edinburgh – Eurekalert.org
Leprosy is one of the world’s oldest and most persistent diseases but the bacteria that cause it may also have the surprising ability to grow and regenerate a vital organ.
Scientists have discovered that parasites associated with leprosy can reprogramme cells to increase the size of a liver in adult animals without causing damage, scarring or tumors.
The findings suggest the possibility of adapting this natural process to renew ageing livers and increase healthspan – the length of time living disease-free – in humans.
Experts say it could also help regrow damaged livers, thereby reducing the need for transplantation, which is currently the only curative option for people with end-stage scarred livers.
Previous studies promoted the regrowth of mouse livers by generating stem cells and progenitor cells – the step after a stem cell that can become any type of cell for a specific organ – via an invasive technique that often resulted in scarring and tumour growth.
To overcome these harmful side-effects, Edinburgh researchers built on their previous discovery of the partial cellular reprogramming ability of the leprosy-causing bacteria, Mycobacterium leprae.
Working with the US Department of Health and Human Services in Baton Rouge, Louisiana, the team infected 57 armadillos – a natural host of leprosy bacteria – with the parasite and compared their livers with those of uninfected armadillos and those that were found to be resistant to infection.
They found that the infected animals developed enlarged – yet healthy and unharmed – livers with the same vital components, such as blood vessels, bile ducts and functional units known as lobules, as the uninfected and resistant armadillos.
