ITS Supplement for Serum-Free Cell Culture: Benefits, Functions, and Applications

ITS is a defined supplement containing insulin, transferrin, and selenium. These components help support cellular nutrient utilization, iron transport, and antioxidant defense. ITS is commonly incorporated into culture media when researchers seek to reduce serum supplementation or establish more controlled culture conditions.

Unlike serum, which contains a complex mixture of proteins, hormones, growth factors, and other biological components, ITS provides three selected ingredients with well-characterized biological functions. This makes it easier to investigate the contribution of specific nutritional factors to cell growth and cellular responses.

The effectiveness of ITS depends on the cell type, basal medium, and overall culture formulation. It is therefore important to evaluate ITS supplementation under application-specific conditions.

1. Insulin: Supporting Cellular Metabolism

Insulin is a peptide hormone that plays an important role in regulating glucose utilization, nutrient metabolism, and cellular growth-related signaling.

In cell culture, insulin can support the uptake and utilization of nutrients and influence metabolic pathways involved in cell maintenance and proliferation. Its biological effects depend on the insulin responsiveness of the target cells and the composition of the culture medium.

In serum-free formulations, insulin can help provide metabolic support that might otherwise be supplied, in part, by serum-derived components.

2. Transferrin: Facilitating Iron Transport

Transferrin is an iron-binding glycoprotein that transports iron to cells through receptor-mediated uptake. Iron is essential for numerous cellular processes, including mitochondrial respiration, DNA synthesis, and the activity of various enzymes.

However, iron availability must be carefully regulated. Excess free iron can promote oxidative reactions, while insufficient iron can impair essential cellular functions.

Transferrin helps deliver iron in a controlled, biologically accessible form. In serum-free culture systems, it can support cellular iron homeostasis and provide an important nutritional component for cells with appropriate transferrin uptake mechanisms.

3. Selenium: Supporting Antioxidant Defense

Selenium is an essential trace element required for the activity of several selenoproteins, including antioxidant enzymes such as glutathione peroxidases and thioredoxin reductases.

These enzymes contribute to the regulation of cellular redox balance and protection against oxidative damage. In cell culture, selenium supplementation can help support antioxidant defense when supplied at an appropriate concentration.

Because selenium requirements and tolerance vary among cell types, its concentration should be optimized for the intended application.

Serum-free cell culture offers several advantages, including greater control over medium composition and reduced dependence on animal-derived serum. Nevertheless, removing serum can also eliminate components that contribute to nutrient transport, metabolic regulation, and cellular protection.

ITS helps address some of these nutritional requirements through its three complementary components.

Key potential benefits include:

• Defined supplementation: Provides insulin, transferrin, and selenium as selected medium components.

• Metabolic support: Helps support nutrient utilization and cellular metabolic activity.

• Iron transport: Supplies transferrin to facilitate regulated iron delivery.

• Antioxidant support: Provides selenium for selenium-dependent cellular functions.

• Formulation flexibility: Can be incorporated into suitable basal media during serum-free culture development.

ITS is not a complete replacement for serum in every application. Additional growth factors, hormones, lipids, amino acids, or other supplements may be required depending on the cell type and culture objectives.

ITS is used in the development and optimization of various serum-free and low-serum cell culture formulations. Its suitability should be confirmed for each target cell type and experimental design.

Mammalian Cell Culture

ITS may be incorporated into selected mammalian cell culture formulations to provide metabolic and nutritional support. Depending on the cell type, it can contribute to the development of media with reduced serum requirements.

Stem Cell Research

Stem cell culture often requires carefully controlled nutritional conditions to support cell maintenance, expansion, and the investigation of cell behavior. ITS may serve as one component of a broader, cell-specific medium formulation.

For pluripotent and adult stem cells, however, ITS alone does not establish the conditions necessary to maintain stemness or direct differentiation. Additional supplements and specialized culture conditions are generally needed.

Primary Cell Culture

Primary cells can be sensitive to changes in their extracellular environment and nutrient availability. ITS may be evaluated as part of a serum-reduced formulation designed to support selected primary cell types.

Performance should be assessed using application-relevant indicators, such as cell viability, morphology, proliferation, and functional characteristics.

Cell-Based Assays and Experimental Models

Defined culture conditions can be valuable in experiments investigating cellular metabolism, signaling, and responses to specific stimuli. ITS can help provide selected nutritional components while reducing some of the compositional complexity associated with serum.

Researchers should consider potential effects of insulin signaling and other supplement components when designing assays that measure metabolic or signaling responses.

A 100X ITS supplement is a concentrated formulation designed to be diluted into the appropriate basal medium at the specified working concentration.

For a formulation intended for 1X final concentration, a typical 100-fold dilution would involve adding 1 volume of supplement to 99 volumes of basal medium. For example, 10 mL of a 100X supplement would be added to 990 mL of basal medium to prepare 1 L of final medium. In the initial culture stage, adding 2%–4% fetal bovine serum (FBS) to the medium containing this product achieves equivalent cell growth performance as the same medium supplemented with 10% FBS. The FBS concentration can be further reduced once cells adapt to the culture condition.

Important: Confirm the manufacturer's recommended dilution ratio and preparation instructions before use. The exact formulation, storage conditions, handling requirements, and compatibility with the target medium should be checked against the product-specific documentation.

For optimal results, researchers should consider the following factors:

1. Basal medium compatibility: Confirm that the basal medium is appropriate for the target cells and compatible with ITS supplementation.

2. Working concentration: Follow the product instructions and optimize the concentration if the application requires additional validation.

3. Culture conditions: Evaluate cell growth, viability, morphology, and relevant functional endpoints.

4. Storage and handling: Follow the product label to maintain supplement quality and stability.

5. Application-specific validation: Confirm that the formulation meets the requirements of the intended experiment or production process.

   
   

EastMabBio provides K002 Insulin-Transferrin-Selenium (ITS, 100X) for researchers developing and optimizing cell culture media.

Designed as a concentrated supplement, K002 offers a practical option for incorporating insulin, transferrin, and selenium into compatible culture formulations. It can support the development of serum-free or low-serum media where these components are required.

When selecting an ITS supplement, researchers should consider formulation compatibility, product specifications, quality documentation, and suitability for their intended application. For detailed information about K002, including its composition, recommended use, and storage requirements, please consult the relevant product documentation or contact the EastMabBio team.

What does ITS stand for in cell culture?

ITS stands for Insulin-Transferrin-Selenium. It is a supplement containing insulin, transferrin, and selenium, which support different aspects of cellular metabolism, iron transport, and antioxidant defense.

What is the purpose of ITS in serum-free media?

ITS provides selected nutritional components that can help support cells cultured in serum-free or low-serum formulations. Its suitability depends on the target cells and the overall medium composition.

Can ITS completely replace fetal bovine serum (FBS)?

No. ITS supplies three selected components but does not reproduce the full range of nutrients, growth factors, hormones, lipids, and other substances found in serum. Additional components may be necessary to support cell growth and function.