Recombinant proteins are proteins obtained and produced using DNA recombination technology or recombinant RNA technology. The specific operational process can be summarized as using the central dogma and gene recombination molecular cloning technology to obtain a recombinant vector that can be translated into the target protein, which is then transferred into host cells capable of expressing the target protein to produce specific recombinant protein molecules. The pathways for obtaining recombinant proteins are divided into in vivo and in vitro production, with expression systems mainly categorized into prokaryotic and eukaryotic expression systems. The most common prokaryotic expression system uses E. coli, while eukaryotic expression systems include yeast protein expression, mammalian cell protein expression (commonly using CHO cells and HEK293 cells), and insect cell protein expression.

 

Figure: Four Major Expression Systems for Recombinant Proteins

 

Recombinant protein technology is primarily used in scientific research, biopharmaceuticals, vaccine development, and diagnostic reagent development. It enables the large-scale production of proteins with specific biological activities, pharmacological activities, or research value, such as cytokines, hormones, enzymes, antibodies (including monoclonal antibodies), therapeutic proteins, and other functional proteins. To date, more than 130 recombinant proteins have been approved by the FDA for clinical use, while over 170 recombinant proteins are produced and used in medicine worldwide. Recombinant proteins are effective drugs that do not cause off-target side effects and have shorter development times compared to small-molecule drugs, overcoming the issues of low yield and difficulty in controlling purity associated with traditional extraction methods. Today, all major pharmaceutical companies develop recombinant proteins as drugs. After more than 30 years of development, recombinant protein drugs have become one of the most important products in the modern biopharmaceutical industry, accounting for more than one-third of the biopharmaceutical market. According to Frost & Sullivan data, the overall market for recombinant protein research reagents in China grew from 500 million yuan in 2016 to 900 million yuan in 2019, with a compound annual growth rate (CAGR) of 20.0%. It is expected to reach 1.9 billion yuan by 2024, with a CAGR of 17.9% from 2019 to 2024. Although China started late in recombinant protein technology, with the improvement of domestic technological levels and intensified market competition, the process of domestic substitution is expected to accelerate.

 

Recombinant Protein Production Process:

 

1) Obtain cDNA and Create Expression Clones: First, the cDNA sequence of the target protein must be obtained and cloned into an expression vector for expression in host cells;

2) Cloning: Transfer the expression vector containing the target protein gene into host cells;

3) Express the Protein in a Suitable System: Select an appropriate host cell system for protein expression, such as E. coli, yeast, or mammalian cells;

4) Small-Scale Expression Testing: Conduct protein expression tests on a small scale to determine expression conditions and protein yield;

5) Protein Purification: Purify the target protein from host cell lysates using various chromatography techniques, such as ion exchange chromatography, gel filtration chromatography, and affinity chromatography;

6) Quality Control: Characterize the purified protein, including its molecular size, purity, and activity;

7) Scale-Up Production: If large quantities of recombinant protein are needed, the production process can be scaled up by culturing transformed host cells in a bioreactor. Bioreactors provide a controlled environment for cell growth and large-scale recombinant protein production.

 

Common Types of Recombinant Proteins:

 

Types of recombinant proteins include therapeutic proteins, industrial enzymes, diagnostic proteins, research tools, vaccines, biomaterials, bioengineering, biosensors, and biocatalysts. They have been widely applied in most popular research areas such as protein structure research, immunoassay reagents, recombinant protein drugs, diagnostic reagent development, antibody drug targets, CAR-T cell therapy targets, Fc receptors, influenza virus proteins, and cytokines. Below are some of the popular recombinant proteins.

 

1. Interleukin (IL)

A class of cytokines produced by various cells and acting on various cells. IL plays an important role in transmitting information, activating and regulating immune cells, mediating T and B cell activation, proliferation, and differentiation, and in inflammatory responses. It is a member of the lymphokine family, produced by lymphocytes, macrophages, and other cells. Interleukins exert their biological effects by specifically binding to cytokine receptors on the surface of target cells. These effects include promoting the proliferation and differentiation of target cells, enhancing anti-infection and tumor cell-killing effects, promoting or inhibiting the synthesis of other cytokines, promoting inflammatory processes, and affecting cell metabolism.

 

Absin Interleukin Recombinant Protein Product List

Product Number	Product Name	Specification
abs00970	Recombinant Mouse IL-2 Protein	5ug
abs00971	Recombinant Mouse IL-3 Protein	10ug
abs00975	Recombinant Mouse IL-7 Protein	10ug
abs00985	Recombinant Mouse IL-33 Protein	10ug
abs04100	Recombinant Mouse IL‐2 Protein	10ug
abs04697	Recombinant Mouse IL-4 Protein	10ug
abs04044	Recombinant Human IL-6 Protein	10ug
abs04045	Recombinant Human IL-2 Protein	10ug
abs04046	Recombinant Human IL-15 Protein	10ug
abs04047	Recombinant Human IL-17A Protein	10ug
More...

 

2. Interferon (IFN)

Interferons are a group of active proteins (mainly glycoproteins) with multiple functions, produced by monocytes and lymphocytes. They have broad-spectrum antiviral activity, affect cell growth, differentiation, and regulate immune functions.

 

Product Number	Product Name	Specification
abs00809	Recombinant Human IL-7 Protein	10ug
abs00918	Recombinant Human IL-29 Protein	5ug
abs05109	Recombinant Human IFN-γ Protein(C-10His)	50ug
abs04123	Recombinant Human IFN-γ Protein(E.coli)	10ug
abs01021	Recombinant Mouse IFN-γ Protein	100ug
abs04127	Recombinant Mouse IFNγ Protein(E.coli)	10ug

 

3. Colony Stimulating Factor, CSF

A group of cytokines that selectively promote the proliferation and differentiation of hematopoietic progenitor cells both in vivo and in vitro, leading to the formation of lineage-specific cell colonies. These include Macrophage Colony-Stimulating Factor (M-CSF), Granulocyte Colony-Stimulating Factor (G-CSF), Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF), and Stem Cell Factor (SCF), among others.

 

Product Number	Product Name	Specification
abs04383	Recombinant Mouse CSF1 Protein	10ug
abs00994	Recombinant Mouse GM-CSF Protein	5ug
abs00839	Recombinant Human GM-CSF Protein	100ug
More...

 

4. Growth Factor, GF

A class of cytokines that mediate the growth and differentiation of various types of cells. Based on their functions and target cells, they are named Transforming Growth Factor (TGF), Nerve Growth Factor (NGF), Epidermal Growth Factor (EGF), Vascular Endothelial Growth Factor (VEGF), Fibroblast Growth Factor (FGF), among others.

 

Product Number	Product Name	Specification
abs04176	Recombinant Human Epidermal Growth Factor Protein	10ug
abs04204	Recombinant Human TGFB1 Protein	10ug
abs05144	Recombinant Human FGF-basic (154aa) Protein	10ug
abs05161	Recombinant Human VEGF165 Protein	10ug
abs01006	Recombinant Mouse bFGF Protein	10ug
abs04222	Recombinant Mouse TGF-β1 Protein	10ug
More...

 

5. Chemokine

A family of cytokines that exhibit chemotactic effects on different target cells, secreted by leukocytes and certain tissue cells. This is a protein family comprising over 60 members. Most members contain four conserved cysteine (C) residues. Based on the arrangement of cysteine residues at the N-terminus, they can be classified into four subfamilies: CXC, CC, C, and CX3C.

 

Product Number	Product Name	Specification
abs00810	Recombinant Human IL-8,72a.a.	5ug
abs04159	Recombinant Mouse CXCL12 Protein	10ug
More...

 

6. Tumor Necrosis Factor, TNF

 

Product Number	Product Name	Specification
abs04294	Recombinant Mouse TNFSF11 Protein	10ug
abs05092	Recombinant Human TNF-α Protein	50ug
abs05160	Recombinant Human TNF-α Protein	100ug
abs04232	Recombinant Human TNF-α Protein	10ug
More...

 

7. CD Antigens

Antigens present on the surface of leukocytes are referred to as CD antigens (also known as leukocyte differentiation antigens), which play a crucial role in the immune response of an organism. As lymphocytes mature, they express different protein receptors on their cell surface, which can help determine the type and stage of maturation of the cells being examined.

 

Product Number	Product Name	Specification
abs04571	Recombinant Mouse CD275 Protein(C-6His)	10ug
abs04611	Recombinant Human CD58 Protein(C-Fc)	10ug
abs04721	Recombinant Human PD-1 Fc Chimera Protein(C-Fc)	25ug
More...

 

8. Enzymes and Regulators

Enzymes are biological catalysts discovered within biological systems, capable of catalyzing specific biochemical processes. The majority of enzymes are proteins with catalytic activity, although some RNA molecules (ribozymes) also exhibit catalytic activity. All biological processes occurring in living organisms are chemical reactions, most of which are regulated by enzymes. Many hereditary human diseases, such as albinism and phenylketonuria, are caused by deficiencies in specific enzymes. Polytoxins or active drugs exert their effects by inhibiting particular enzymatic reactions.

 

Product Number	Product Name	Specification
abs04756	Recombinant Human ACE2 Protein(C-His-Avi)	100ug
abs06069	Recombinant Schistosoma Japonicum GST Protein(C-10His)	50ug

 

9. Immune Checkpoint Proteins

Immune checkpoint (ICP) molecules refer to ligand-receptor pairs that exert inhibitory or stimulatory effects on immune responses. Immune checkpoints play a crucial immunoregulatory role in maintaining immune homeostasis and preventing autoimmunity. The majority of reported immune checkpoint proteins are expressed on cells of the adaptive immune system, particularly T cells, and the innate immune system.

 

Product Number	Product Name	Specification
abs01295	Recombinant Human Galectin-3 Protein	10ug
abs04602	Recombinant Human Galectin 9 Protein(C-6His)	50ug

 

Absin also specializes in providing a variety of recombinant proteins, such as extracellular matrix proteins, modifying enzymes, angiopoietins, fluorescent proteins, apolipoproteins, adipokines, transcription factors, CAR-T related proteins, IVD antigen proteins, immunoglobulins, and more. Click here to explore more recombinant protein products.

 

Recombinant Human IL-15 Protein(abs05147)

Interleukin-15 (IL-15) is a cytokine discovered in 1994 that supports the homeostasis of cytotoxic immune cells and exhibits a wide range of biological activities. IL-15 stimulates the proliferation of activated T cells, promotes the induction of cytotoxic T lymphocytes (such as CD8+ cells), and enhances the generation, proliferation, and activation of natural killer (NK) cells. Therefore, IL-15 is being increasingly used in combination with other therapies, such as checkpoint inhibitors, monoclonal antibodies, chemotherapy, radiotherapy, and CAR-T cells, in the rapidly expanding field of cancer immunotherapy. These combinations target multiple mechanisms to enhance immune responses against tumors, providing advantages in the control and treatment of cancer.

 

Product Features:

Species	Human
Source	E. coli
Molecular Weight	1 k2Da (Reducing)
Appearance	Lyophilized powder
Sequence	Asn49-Ser162 NWVNVISDLKKIEDLIQSMHIDATLYTESDVHPSCKVTAMKCFLLELQVISLESGD ASIHDTVENLIILANNSLSSNGNVTESGCKECEELEEKNIKEFLQSFVHIVQMFINTS
Purity	＞95% SDS-PAGE
Endotoxin Level	＜1 EU/μg (LAL)
Activity	EC50 < 1 ng/mL

 

Experimental Results:

 

Dose-dependent stimulation of CTLL-2 proliferation with EC50 < 1 ng/mL

Absin provides antibodies, proteins, ELISA kits, cell culture, detection kits, and other research reagents. If you have any product needs, please contact us

Absin Bioscience Inc. Email: worldwide@absin.cn

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