The existence of nanobodies can be traced back to the 1990s, when scientists accidentally discovered an unusual antibody that was composed only of heavy chains and had no light chain structure while studying the immune system of camelids. Subsequent studies revealed that the variable region (VHH) of these heavy-chain antibodies itself has complete antigen recognition and binding functions, a discovery that has sparked widespread interest in this type of single-domain antibody.

Nanobodies, also known as single-domain antibodies (sdAbs), are a special class of antibody fragments that are derived from heavy-chain antibodies (HCAbs) of camelids (including camels, alpacas, and Virginia alpacas). Unlike traditional antibodies, nanobodies consist of a single, fully functional antibody binding domain without light chains and complex structures, while the variable region (VHH) of its heavy chain can independently form a complete antigen binding site. Due to its small molecular weight, usually about 15kDa, it is named "nano" antibody.

With the continuous advancement of science and technology, the field of biomedicine is witnessing a revolution led by nanobodies. These extremely small antibody molecules are gradually becoming an indispensable tool in biotechnology and drug development with their unique advantages and wide application potential.

一. Structural Characteristics of Nanobodies

Nanobodies are a special type of antibody with some unique structural characteristics, which give them unique advantages in the fields of biomedicine and research. The following are several key structural characteristics of nanobodies:

1. Single Heavy Chain Variable Region (Single Variable Domain):

(1) Nanobodies are isolated from heavy-chain antibodies (HCAbs) of camelids (such as camels and alpacas) and consist of a single variable region (VHH).

(2) They lack the heavy chain constant region and light chain of traditional antibodies, but are composed of only a heavy chain variable region (VHH) of about 15 kDa.

(3) This VHH region can independently complete the complete antigen binding function.

2. Miniaturized Structure:

(1) The molecular weight of nanobodies is usually around 12-15 kDa, which is much smaller than traditional full-size antibodies (about 150 kDa).

(2) This small size gives nanobodies better tissue penetration and allows them to reach areas in the body that are difficult for full-size antibodies to reach.

3. High Stability:

(1) Nanobodies show extremely high temperature and chemical stability and can maintain activity over a wide temperature and pH range.

(2) This property makes nanobodies suitable for biomedical and industrial applications that require high stability.

4. Easy to Produce and Modify:

(1) Nanobodies can be efficiently produced through conventional microbial expression systems (such as Escherichia coli and yeast), which helps to reduce production costs.

(2) Due to their single protein structure, nanobodies are also easier to engineer, such as adding drug conjugates, improving affinity, or increasing specificity.

5. Unique Antigen Recognition Properties:

(1) Nanobodies can recognize and bind to some antigenic epitopes that conventional antibodies cannot recognize, such as protein recesses, active centers, etc.

(2) This unique binding property gives them unique advantages in antigen recognition and disease diagnosis.

6. Low Immunogenicity:

(1) Nanobodies generally exhibit low immunogenicity, which means that they are less likely to cause an immune response in the body.

(2) This is particularly important for clinical applications, as low immunogenicity means that treatments using nanobodies may produce fewer adverse immune responses.

These structural features give nanobodies broad application prospects in many fields, including but not limited to drug development, disease treatment, diagnostic testing, and basic scientific research.

二. Research Hotspots and Applications of Nanobodies

1. Targeted Drug Delivery System

Due to their small size, good penetration, and ability to specifically recognize and bind to specific targets on the cell surface or in the body, nanobodies have been widely studied as targeted drug delivery systems. This strategy can be used to precisely deliver drugs to lesions, improve drug efficacy, and reduce adverse effects on healthy tissues. At present, the research focus in this field includes improving the drug loading of nanobodies, controlling drug release, and minimizing immunogenicity and toxicity.

2. Tumor Diagnosis and Treatment

The potential of nanobodies in tumor diagnosis and treatment is receiving widespread attention. Due to their miniaturization and high affinity, they can accurately identify tumor-associated antigens, and nanobodies are being developed as tools for tumor imaging and biomarkers, thereby improving the accuracy of early diagnosis. At the same time, nanobodies can also be used for targeted therapy, by delivering radioisotopes, toxins or anti-tumor drugs directly to tumor cells, enhancing the therapeutic effect and reducing side effects.

3. Infectious Disease Control

Nanobodies have attracted much attention for their use in antiviral treatment, especially in the prevention and treatment of viral diseases such as HIV, influenza, and coronavirus. They can neutralize viruses and block the interaction between viruses and host cells, and are powerful tools for the development of new antiviral therapies. Researchers are engineering nanobodies to improve their affinity and specificity to provide more effective strategies for the prevention and treatment of infectious diseases.

4. Discovery of Disease Biomarkers

Nanobodies play a key role in the identification and validation of disease biomarkers. They are not only used to develop highly sensitive and specific diagnostic methods, but also to reveal the molecular mechanisms of disease occurrence. Currently, the focus of research is on discovering new biomarkers associated with various diseases (such as autoimmune diseases, neurodegenerative diseases, etc.) and using nanobodies for effective detection.

5. Basic Biological Research

Nanoantibodies are also an important tool for basic biological research. Due to their high operability and specificity, nanoantibodies are used to study the structure and function of proteins, reveal cell signaling pathways, and serve as probes for microscopic imaging techniques. Nanoantibodies are widely used in fields such as cell imaging and immunoprecipitation. Through these studies, scientists can gain a deep understanding of life processes and disease development.

With its leading technology platform and rich experience, Tek Biotech provides global customers with complete solutions from the discovery, design to production and application of nanoantibodies. Our distinctive services, from providing customized nanoantibody discovery, screening high-affinity antibodies from a large antibody library through high-throughput technology, to subsequent functional verification, affinity optimization, and even large-scale production, all demonstrate the industry's advancement. To ensure the highest standard of product delivery, Tek Biotech strictly implements a full range of quality control processes. Nanobodies are emerging in the biomedical field due to their uniqueness. They not only play a key role in drug delivery and disease diagnosis and treatment, but also shine in basic biological research. Tek Biotech is constantly innovating for this purpose and working with partners to unlock more application potential and value of nanobodies.