PeptiGrowth Inc. Successfully Develops a Novel Synthetic Peptide: IL-2 Peptide and Launches Evaluation Samples

2026/10/16

PeptiGrowth Inc. (Headquarters: Chiyoda-ku, Tokyo, President: Jun Minamitani) has successfully developed a novel synthetic peptide called “IL-2 Peptide” which is functionally equivalent to recombinant IL-2. Samples will be available beginning October 16th, 2026. The commercial product is planned to be available around December 2026.

Development of Synthetic Peptide Growth Factors by PeptiGrowth

Conventional growth factors and cytokines used in the manufacturing of regenerative medicine and cell therapy products face various quality challenges such as lot-to-lot variation, potential contamination with biological impurities, low stability, and high cost. PeptiGrowth has been working on the development of a series of synthetic peptides that can address these challenges while maintaining equivalent function to the conventional growth factors and cytokines on the market. Our peptides are completely chemically synthesized and animal component-free, enabling xeno-free and chemically defined cell culture media.

About the IL-2 Peptide

Mechanism of IL-2 Peptide
IL-2 Peptide is a dimeric peptide composed of two cyclic peptides that selectively bind to IL-2 receptor β (IL-2Rβ) and the common gamma chain (γc), respectively. Similar to IL-2, it exhibits agonistic activity by inducing heterodimerization of IL-2Rβ and γc (Figure 1).

*This is for illustrative purpose.

Figure 1 Schematic Illustration of the Mechanism of Action of IL-2 Peptide

T Cell Expansion Activity of IL-2 Peptide
As a comparative functional study, human peripheral blood mononuclear cells (PBMCs) were stimulated and cultured with either IL-2 Peptide or commercially available recombinant human IL-2, and T cell expansion activity was evaluated by flow cytometry (Figure 2).
We confirmed that IL-2 Peptide exhibited T cell expansion and maintenance at molar concentrations ranging from equimolar to three-fold relative to recombinant human IL-2 (Figures 3-5). Additional functional evaluations are currently ongoing.

Figure 2 T-cell expansion assay

Figure 3 Cell proliferation rate

Figure 4 Live lymphocytes rate

Figure 5 CD3+ cells rate

We anticipate that IL-2 Peptide will be applicable in cell therapy, particularly for the culture and functional enhancement of immune cells such as T cells, NK cells, and NKT cells.

Evaluation Sample Overview

Product name	IL-2 Peptide
Product form	Vacuum-dried powder
Storage conditions	-20℃ or below
Purity	≥95% by HPLC
Molecular weight	5507.35 (5963.44 (Trifluoroacetate))
Size	10 µg per vial

*The evaluation samples are supplied as trifluoroacetate (TFA) salts. Therefore, the molecular weight of the TFA salt form is shown above. The commercial product is planned to be supplied as acetate salt, consistent with our other products.
* Samples are not eligible for an Animal Component Free (ACF) certificate. The commercial products will be planned to be supplied with an ACF certificate.
*This evaluation sample is for testing and research use only (RUO).
*There is a possibility that the specifications can change.

Purchasing Information

Commercial products are scheduled to be launched around December 2026 and will be available in the following package sizes: 10 μg, 100 μg, and 1 mg.
If you would like to purchase our products, please contact us using the information below.
For customers who would like to purchase GMP compliant products as well as the above PG products in bulk scale, please contact us using the information below.

Distributor

For distributor information, please visit the following page:
https://peptigrowth.com/en/distributor/

Learn more about IL-2 Peptide: https://peptigrowth.com/en/products/pg-015/
Request a free sample: https://forms.cloud.microsoft/pages/responsepage.aspx?id=_W3S6ixPNk-fvbmyxq4_d4P9lguwXSJBlCpHevH9DR9UQkxNRk44RTNBVVQ0UktHWTJGWlpXRTZLVS4u&route=shorturl

Development of other peptides from PeptiGrowth

We have developed peptides targeting numerous growth factors and cytokines. To date, we have launched 15 products and plan to launch additional growth-factor peptide targeting IL-7 in 2027. Details will be updated on our website. If you are interested, please contact us using the following contact information.