Relevance: Mains: G.S paper III: Bio-Technology
Why in News?
In a recent development remission observed for the last 18 months after antiretroviral therapy (ART) was stopped following stem cell transplantation in London. (Remission is when HIV RNA is undetectable in blood.)
What is HIV?
- HIV is a virus that attacks cells in the immune system.
- The virus destroys a type of white blood cell in the immune system called a T-helper cell.
- T-helper cells are also referred to as CD4 cells. · As HIV destroys more CD4 cells and makes more copies of itself, it gradually weakens a person’s immune system.
- If HIV is left untreated, it may take up to 10 or 15 years for the immune system to be so severely damaged that it can no longer defend itself at all.
- However, the rate at which HIV progresses varies depending on age, general health and background.
HIV stands for human immunodeficiency virus.
- People with HIV can enjoy a long and healthy life by taking antiretroviral treatment.
- HIV is found in semen, blood, vaginal and anal fluids, and breastmilk.
- HIV can’t be transmitted through sweat, saliva or urine.
- Using external (or male) condoms or internal (or female) condoms during sex is the best way to prevent HIV and other sexually transmitted infections.
- If you inject drugs, always use a clean needle and syringe, and never share equipment.
- HIV transmitted from mother to baby, during birth or afterwards through breastfeeding.
What is AIDS?
- AIDS is a set of symptoms (or syndrome as opposed to a virus) caused by HIV. · A person is said to have AIDS when their immune system is too weak to fight off infection, and they develop certain defining symptoms and illnesses. · This is the last stage of HIV, when the infection is very advanced, and if left untreated will lead to death.
- AIDS stands for acquired immune deficiency syndrome; it’s also called advanced HIV infection or latestage HIV.
- AIDS is a set of symptoms and illnesses that develop as a result of advanced HIV infection which has destroyed the immune system.
- Although there is no cure for HIV, with the right treatment and support, people living with HIV can enjoy long and healthy lives.
What are stem cells?
- Our body is made up of many different types of cell.
- Most cells are specialised to perform particular functions, such as red blood cells that carry oxygen around our bodies in the blood, but they are unable to divide.
- Stem cells provide new cells for the body as it grows, and replace specialised cells that are damaged or lost.
- They have two unique properties that enable them to do this: o They can divide over and over again to produce new cells.
As they divide, they can change into the other types of cell that make up the body.
- A stem cell is a cell with the unique ability to develop into specialised cell types in the body.
- In the future they may be used to replace cells and tissues that have been damaged or lost due to disease.
- In other words Stem cells are a class of undifferentiated cells that are able to differentiate into specialized cell types.