Unlocking the Power of IL-15 -- PBL Assay Science Newsletter

HOME
取扱メーカー速報
Unlocking the Power of IL-15 -- PBL Assay Science Newsletter

メーカー速報

PBL Assay Science

2025 年 3 月 3 日

PBL Assay Science

ナカライテスク

取扱メーカー速報は、取扱メーカーの商品・サービスに関する情報をいち早く紹介するコンテンツです。情報発信のスピードを重視しているコンテンツのため、現時点で法規制や取り扱いを確認できていない商品、定価を設定できていない商品があります。ご要望やご照会を受けた商品について、法令整備や在庫の充実を図ります。

メールマガジン（転載）

Unlocking the Power of IL-15: A Key Player in Immune Regulation

Interleukin 15 (IL-15) is a critical cytokine in immune regulation, supporting NK cells and memory CD8+ T cells. IL-15 functions through trans-presentation, where it binds to IL-15Rα receptor subunit on antigen-presenting cells and activates immune responses via JAK-STAT, P13K-Akt, and MAPK pathways. It plays a key role in cancer immunotherapy, chronic infections, and autoimmune diseases, with promising therapies such as IL-15 agonists and IL-15-armored CAR-T cells under investigation.

The IL-15 receptor complex is composed of three subunits:IL-15Rα, IL-2R/15Rβ, and the common gamma chain (γc). IL-15Rα subunit has a much higher affinity for IL-15 than the other subunits, which allows IL-15 to be effectively presented to immune cells. The IL-15/IL-15Rα complex can exist in both membrane-bound and soluble forms. The serum levels of the human IL-15/IL-15Rα complex are crucial for understanding its biological functions and relevance in health and disease.

Serum IL-15 levels generally fall in the low-pg/ml range (<10 pg/ml), with the IL-15/IL-15Rα complex present at similarly low concentrations. However, elevated levels of this complex have been observed in autoimmune diseases, chronic viral infections, and cancers, often reflecting increased immune activation, inflammation, or compensatory immune regulation in response to disease

IL-15/IL-15Ra Complex

Human IL-15/IL-15Ra Complex

The IL-15/IL-15Rα complex is essential for immune activation and homeostasis, supporting natural killer (NK) cells, CD8+ T cells, and memory T cells. While IL-15 primarily functions through localized trans-presentation, its presence in serum indicates a broader systemic role in immune regulation. This complex provides a pro-survival signal, ensuring long-term immune protection against persistent infections and tumors. Additionally, it regulates inflammatory responses, where elevated serum levels may either enhance protective immunity or contribute to pathological inflammation in diseases.

In autoimmune diseases such as rheumatoid arthritis, multiple sclerosis, and celiac disease, increased IL-15/IL-15Rα levels can promote the persistence of autoreactive T cells and NK cells leading to chronic inflammation and tissue damage. In chronic viral infections such as HIV and hepatitis, elevated levels may help sustain an effective immune response, but prolonged exposure could also contribute to immune exhaustion and dysregulation. In cancer, the IL-15/IL-15Rα complex plays a dual role- enhancing anti-tumor immunity by activating NK and CD8+ T cells, while chronic elevation may promote immune evasion or immunosuppressive mechanisms within the tumor micro-environment.

The IL-15/IL-15Rα complex is being actively explored as a therapeutic target in cancer immunotherapy due to its ability to eliminate cancer cells. Monitoring serum levels of this complex could be crucial for optimizing such treatments. Additionally, these serum levels hold biomarker potential, as elevated concentrations may indicate immune activation or inflammation in diseases, making it useful for tracking disease progression and treatment efficacy.

Additional Readings:

Perera, et al., The role of interleukin-15 in inflammation and immune responses to infection: implications for its therapeutic use
Fiore et al., Interleukin-15 and cancer: some solved and many unsolved questions
Silvestre et al., Engineering NK-CAR.19 cells with the IL-15/IL-15Rα complex improved proliferation and anti-tumor effect in vivo
Meghnem et al., Selective Targeting of IL-15Rα Is Sufficient to Reduce Inflammation

VeriKine-HS Total Human IL-15 ELISA

Measures both free IL-15 and IL-15/IL-15Rα complex
Quantifies basal endogenous IL in serum, plasma, and cell culture media
100% of healthy donor serum samples tested exhibited quantifiable IL-15 above LLOQ (0.51 pg/ml)

Find out more