Malady to a miracle: Leprosy bacteria grow liver in armadillos, gives hope for human organ regeneration

Subject: Environment

Context-

Leprosy has long been associated with a life of ostracism. However, the bacteria causing this debilitating disease may offer some hope on the regenerative medicine horizon.

About Leprosy-

Leprosy is also known as Hansen’s Disease. Leprosy is a chronic, progressive bacterial infection.
Caused by Mycobacterium Leprae, which is an acid-fast rod-shaped bacillus.
Leprosy is one of the oldest diseases in recorded history, afflicting humanity since time immemorial. A written account of Leprosy date as far back as 600 B.C.
Genetic evidence supports the existence of Leprosy infections in hundred-thousand-year-old remains.

Areas of Infection:

Mode of Transmission:

Mainly by breathing airborne droplets from the affected individuals. It can be contacted at any age.

Symptoms:

Red patches on the skin, skin lesions, numbness in arms, hands, and legs, ulcers on the soles of feet, muscle Weakness and excessive weight loss.
It usually takes about 3-5 years for symptoms to appear after coming into contact with Leprosy causing bacteria. The long incubation period makes it difficult for doctors to determine when and where the person got infected.
If not treated on time, Leprosy can lead to significant disability, disfigurement, permanent nerve damage in arms and legs and even loss of sensation in the body.

Cure:

Leprosy is curable with a combination of drugs known as Multi-Drug Therapy (MDT).

What researchers have found-

A group of researchers have found that armadillo livers grew substantially when infected with Mycobacterium leprae.
The pathogen was able to maintain liver function and keep its exquisite architecture intact, giving rise to something that looked like stem cells.
The research documents the in-vitro discovery of Mycobacterium leprae’s ability to reprogramme adult Schwann cells (the bacteria’s preferred host niche in the peripheral nervous system) to a stage of progenitor/stem-like cells.
Armadillos are among the few animals that leprosy bacteria infect.
The bacteria was performing something akin to ‘biological alchemy’ — a bacterial pathogen was changing the biology of infected cells to become more ‘valuable’ such that it can promote the growth of a vital organ like the liver in living animals.
The leprosy bacteria need functional cells to function within it because of their dependency on the host to survive and replicate.

Significance of the findings-

Stem cells-

Special human cells that have the capability to develop into wide-ranging types of cells in the human body, from muscle cells to brain cells, are called stem cells.

2 unique properties of Stem Cells-

Different Types of Stem Cells-

Classification based on the formation of cells at different phases of human lives and
Classification based on its ability to form into different specialized cells.

Classification based on Stem Cells formation at different times of human lives

These are the Stem cells that exist only during the earliest stage of development.

These are the cells that can multiply when there is a need to repair adult organs and tissues.
These cells are present in almost all organs of the human body.
They are multipotent i.e. they can give rise to a limited number of mature cell types, usually corresponding to the tissues in which they reside. A most well-known example is the blood-forming (hematopoietic) stem cells from bone marrow that give rise to different blood cells in our body.
Some tissue-specific stem cells can only give rise to one or two mature cell types and are called unipotent and bipotent, respectively. Stem cells found in the skin produce new skin cells and are an example of unipotent stem cells.

These cells are not found in the body but made in the laboratory from cells of the body.
The iPSC cells have properties similar to those of embryonic stem cells.
Human iPSC’s were generated in 2007.

Classification based on Stem cells ability to develop into different specialized cells

These Stem Cells can transform themselves into any type of cell in the human body except those kinds that are required to support and develop a fetus in the womb. ESC’s and iPSC’s are pluripotent stem cells.

Use of stem cells in the Medical field-

The only stem cells currently used to treat disease are hematopoietic stem cells. These are blood cells forming adult stem cells found in the bone marrow.
Researchers believe that stem cells would be able to treat a multitude of ailments like
- Heart disease
- Type 1 diabetes
- Spinal cord injury
- Alzheimer’s disease
- Rheumatoid Arthritis