What is the Difference Between Finite and Continuous Cell Lines

The main difference between finite and continuous cell lines is that finite cell lines are capable of undergoing only a limited number of population doublings whereas continuous cell lines are apparently capable of an unlimited number of population doublings, often referred to as immortal cell culture. Furthermore, the growth rate of finite cell lines is slow while the growth rate of continuous cell lines is fast. 

Finite and continuous cell lines are two types of cell lines, which are particular cell lineages produced by cloning or other selection methods. 

Key Areas Covered 

1. What are Finite Cell Lines
     – Definition, Features, Importance
2. What are Continuous Cell Lines
     – Definition, Features, Importance
3. What are the Similarities Between Finite and Continuous Cell Lines
     – Outline of Common Features
4. What is the Difference Between Finite and Continuous Cell Lines
     – Comparison of Key Differences

Key Terms 

Cell CUlture, Cloning, Continuous Cell Lines, Genetic Transformations, Immortal, Finite Cell Lines, Ploidy 

What are Finite Cell Lines 

Finite cell lines are cell lines with a limited lifespan in the culture. These cells normally undergo 20-100 population doublings. After that, their growth rate declines and they eventually die. However, the number of cell divisions depends on the species, type of cells, and culture conditions.

Figure 1: The H9 Cell Line of Human Embryonic Stem Cells

Furthermore, finite cell lines may have undergone several genetic transformations. However, these transformations have not brought cells in the finite cell lines into an immortal stage. 

What are Continuous Cell Lines 

Continuous cell lines are the cell lines capable of undergoing an unlimited number of cell divisions in the culture. Therefore, it is said that the cells in a continuous culture have developed immortal characteristics. Further, this immortality is caused by neoplastic or malignant transformations. 

Figure 2: Immortal HeLa Cells

Furthermore, some of the other important properties of continuous cell lines are reduced serum requirement, reduced density limitation growth, and the ability to grow in semisolid media. Moreover, the continuous cell lines are aneuploid or having an abnormal number of chromosomes.  

Similarities Between Finite and Continuous Cell Lines 

• Finite and continuous cell lines are two types of cell populations classified based on their ability to divide. 
• Both underwent different types of genetic transformations. 
• Moreover, they play a vital function in biotechnology and research. 

Difference Between Finite and Continuous Cell Lines 

Definition 

Finite cell lines refer to the cell lines that usually divide only a limited number of times before losing their ability to proliferate which is a genetically determined event known as senescence. Continuous cell lines, on the other hand, refer to the finite cell lines that undergo transformations and acquire the ability to divide indefinitely. Thus, this is the main difference between finite and continuous cell lines.

Ploidy 

Also, the finite cell lines are euploid or diploid while continuous cell lines are aneuploid or heteroploid. 

Type of Transformation 

Furthermore, finite cell lines have undergone normal transformation while continuous cell lines have undergone transformations that alter their growth into immortal stages. 

Anchorage Dependence 

Besides, finite cell lines are anchorage dependent while continuous cell lines are not anchorage dependent. 

Type of Cell Cultures 

Moreover, finite cell lines are grown in monolayer cultures while continuous cell lines can be grown in both monolayer and suspension cultures. 

Maintenance 

Finite cell lines cannot be maintained by serial passaging while continuous cell lines can be maintained by serial passaging. 

Nutrient Requirement 

Nutrient requirement is also a difference between finite and continuous cell lines. Finite cell lines have a high nutrient requirement while continuous cell lines have a low nutrient requirement. 

Cloning Efficiency 

While finite cell lines have a low cloning efficiency, continuous cell lines have a high cloning efficiency. Hence, this is also a difference between finite and continuous cell lines.

Markers 

Additionally, one other difference between finite and continuous cell lines is that the finite cell lines possess tissue-specific markers whereas continuous cell lines possess chromosomal, enzymatic, and antigenic markers.

Functions of the Parent Cells 

Moreover, finite cell lines may retain special functions of the parent cells while continuous cell lines have often lost special functions of the parent cells. 

Growth Rate 

The growth rate is another difference between finite and continuous cell lines. Finite cell lines have a slow growth rate while continuous cell lines have a fast growth rate. 

Yield 

While finite cell lines produce low yields, continuous cell lines produce high yields.

Conclusion 

Finite cell lines are the cell lines with a limited lifespan. The cells of a finite cell line may have undergone several transformations, but they also express the special functions of the parent cells. However, their cloning efficiency is low and have slow growth rates. On the other hand, continuous cell lines are the cell lines transformed in such as a way to become immortal in the culture. These cells have low nutrient requirements and show high growth rates and cloning efficiency. Therefore, the main difference between finite and continuous cell lines is their lifespan in the culture.  

Reference:

1. Guwahati, IIT. “Cell Culture|Biotechnology – Cell Biology.” NPTEL, Available Here.

Image Courtesy:

1. “Humanstemcell” By Ryddragyn at English Wikipedia – Transferred from en.wikipedia to Commons. (Public Domain) via Commons Wikimedia   
2. “Ki67-Tubulin-2” By GerryShaw – Own work (CC BY-SA 4.0) via Commons Wikimedia