HeLa Cells
HeLa cells are a type of cell culture cells for scientific research that are frequently used. These cells belong to Henrietta Lacks, a woman who suffered cervix-uterine cancer in the mid of 20th century.
But, what makes these cells so special? Well, they survive outside the human body and they could be divided in the laboratory constantly. These cells can be divided in 24 hours and can contaminate any cultivation with a single cell.
Also, they adhere to the walls of the culture chamber, they exhibit contact inhibition, they’re robust, easy to cultivate on standardized media, easy to culture viruses with them, etc.
Normal cells of a human can be divided fifty times, because of Hayflick’s limit. The Hayflick limit is the number of times a normal human cell population will divide until the division stops and the cell dies. That is because of the telomeres, they are associated with each cell's DNA and they will get shorter with each new division until they have a critical length.
But, HeLa cells don’t have a Hayflick’s limit, so they can live forever.
Also, nowadays, researchers think that the development and resistance to the apoptosis of these cells is caused by the papilloma virus 18 and by alterations to chromosomes one, three, five and six. The papilloma virus makes a protein that degrades the p53 protein, which is the tumour suppressor.