CRM-197 (Carrier Protein)

Description

1. Introduction

CRM-197 is a recombinant carrier protein produced through E. coli fermentation. It is a non – toxic single – amino – acid mutant of diphtheria toxin. Notably, its molecular weight is comparable to that of diphtheria toxin. Unlike traditional diphtheria toxin, CRM-197 does not require formaldehyde detoxification. This characteristic not only makes it safer but also better protects T – cell helper epitopes.

Compared to diphtheria toxoid, CRM-197 offers several advantages. Its non – toxicity and single – component nature eliminate the need for formaldehyde and other chemical detoxification treatments. As a result, it has a higher purity, often exceeding 90%.

2. Key Features

2.1 Binding Properties

CRM-197 exhibits strong binding capabilities. It can bind to a wide variety of molecules and membranes, and its binding is not affected by temperature or pH variations. Throughout the processing stages, it consistently maintains its three – dimensional structure. The lysine residues on the molecule are more exposed, which allows it to mediate polysaccharide attachment using a junction molecule.

2.2 Conjugation Versatility

CRM-197 can be conjugated with other small molecules such as polysaccharides, oligosaccharides, and peptides. This conjugation ability enables the development of conjugate vaccines against a diverse range of infectious diseases.

3. Applications in Vaccine Development

3.1 Approved Vaccines

CRM-197 has already been successfully incorporated into several well – known vaccines. It is a key component in the Hib polysaccharide conjugate vaccine. Additionally, it is used in both the 7 – valent and 13 – valent pneumonia polysaccharide conjugate vaccines. Monovalent or multivalent polysaccharide conjugate vaccines for groups A, C, Y, and W135 have also been approved for use in major markets including the United States, Europe, Canada, and China.

Moreover, pentavalent (diphtheria, tetanus, pertussis, hepatitis B, and Hib) and quadrivalent (diphtheria, tetanus, pertussis, and Hib) vaccines based on CRM-197 have been successfully marketed and approved.

3.2 Potential for Bacterial Infectious Disease Vaccines

CRM-197 shows great promise in the development of vaccines against various bacterial infectious diseases. It can be used in the creation of vaccines for tuberculosis, typhoid fever, group A streptococcus, and nosocomial infections.

4. Applications in Cancer Therapy and Immunotherapy

4.1 Cancer Cell Inhibition

CRM-197 has the ability to inhibit the growth and reproduction of cancer cells. It achieves this by binding to the soluble form of epidermal growth factor HB – EGF and its precursors. By doing so, it prevents the activation of the ErbB receptor, which in turn interrupts protein synthesis and impairs mitosis.

4.2 Synergistic Effects in Cancer Treatment

• Ovarian Cancer: CRM-197 can work synergistically with paclitaxel to inhibit the development of ovarian cancer.

• Glioma Cells: It can act as a chemosensitizing agent, enhancing the cytotoxicity of gemcitabine in human glioma cells. Additionally, it can help drugs cross the blood – brain barrier, which is crucial for treating brain tumors.

• Blood Toxicity: CRM-197 may also assist in reducing the blood toxicity of certain drugs.

4.3 Cancer Vaccine Carrier and Immunotherapy

CRM-197 is frequently used as a carrier in cancer vaccines and plays a significant role in cancer immunotherapy. It has been involved in the treatment and prevention of numerous cancers, including glioma, pancreatic cancer, oral cancer, leukemia, triple – negative breast cancer, and adrenocortical cancer.

5. Product Information

CRM-197 is a highly versatile protein with a wide range of applications in both vaccine development and cancer therapy. Whether you are looking to develop a new vaccine or explore innovative cancer treatment options, CRM-197 offers significant potential. Contact us today to learn more about how CRM-197 can meet your needs.