Scientists for first time grow miniature human oesophagus in lab

Scientists for first time have successfully grown oesophageal organoids, a miniature, functional version of human food pipe using pluripotent stem cells (PSCs) in laboratory.

• This bioengineered oesophageal organoids paves way for new ways to study and test drugs against gut disorders.
• It may also lead to personalised diagnostic methods and focus in part on developing regenerative tissue therapies to treat or cure GI disorders.
• It will help to study birth defects like esophageal atresia, organoids, eosinophilic esophagitis and Barrett's metaplasia.
• Moreover, bioengineered genetically matched esophageal tissue can also be transplanted in individual patients.

About Oesophagus:

• It is a long muscular tube that is part of the digestive system that connects mouth to stomach to actively pass food. 
• It is also called- gastro-intestinal tract (GI tract or gullet or food pipe).
• It is around 25cm long in adults. 
• After food is swallowed, the walls of oesophagus squeeze together (contract) and moves the food down to the stomach.
• The area where oesophagus joins stomach is called gastro-oesophageal junction.

Oesophagus has four layers:

Mucosa- Inner layer, which is moist to help food pass smoothly into stomach.
Submucosa- Contains glands that produce mucus (phlegm), which keeps oesophagus moist.
Muscularis- It is muscle layer, which pushes food down to stomach.
Adventitia- It is outer layer, which attaches oesophagus to nearby parts of body.

• Oesophagus can be affected by congenital diseases, such as oesophageal atresia, a medical condition causing narrowing or malformation of oesophagus due to genetic mutations.
• Other diseases related to it includes oesophageal cancer, gastroesophageal reflux disease (GERD), or rare ailment called achalasia, a disease affecting muscles of lower oesophagus that prevents contraction of organ and passage of food.

What is Stem cell?

• Stem cell is an undifferentiated cell of amulticellular organism which is capable of giving rise to indefinitely more cells (through mitosis) of same type and from which, certain other kinds of cells may be formed by the cellular differentiation.

There are two types of stem cells that are widely used:
Embryonic stem cells:

• They come from human embryos that are three to five days old.
• They are harvested during a process called in-vitro fertilization. 
• They are known as pluripotent stem cells.
• These cells can give rise to virtually any other type of cell in the body.

Induced pluripotent stem cells (iPSCs):

• They can differentiate into all types of specialized cells in body. 
• They can potentially produce new cells for any organ or tissue.

Question:

Q. Scientists for the first time have successfully grown the miniature and functional version of which human organ using pluripotent stem cells (PSCs) in laboratory?
a. Heart
b. Oesophagusc. Gall Bladder
d. Liver