Since the vaccine is used in a large number of healthy persons, the adverse reaction after vaccination should be lower than the drug normally used for treatment. The identity tests for vaccines should be high standard.

Preventive vaccines are usually administered to healthy humans. Ensuring their safety and efficacy is therefore very crucial. Preclinical assessment is a prerequisite for the transfer of candidate vaccines from the laboratory to the clinic, including all aspects of animal testing, product characterization, proof of concept/immunogenicity studies, and safety testing prior to human clinical trials.

Cell based vaccine is a vaccine developed from mammalian cell lines rather than embryonic chicken eggs. Cell culture techniques are used as a complementary and alternative platform for current egg-based strategies. Potential applications in the development of viral vaccines, particularly influenza vaccine, have been extensively studied in recent years.

The strategy of using live bacterial cells as vehicles to deliver recombinant antigens has emerged over the past 20 years as an interesting alternative for the development of new vaccines. With the development of genetic engineering techniques, recombinant microorganisms and pathogens are capable of expressing heterologous proteins in different cell compartments, thereby increasing their antigenic potential for vaccines against viruses, bacteria, and parasites.

Nucleic acid vaccines were introduced decades ago but have already been widely used in infectious and malignant diseases. Nucleic acid vaccination is a technique for protecting against disease by injection with genetically engineered DNA (as a plasmid) or RNA (as mRNA). In contrast to recombinant bacteria or virus vaccines, nucleic acid vaccines consist only of DNA or RNA, which is uptake by cells and transformed into protein.

A conjugate vaccine consists of a polysaccharide antigen that is conjugated to a carrier molecule. The conjugate vaccine is produced by covalently linking the poor antigens to the strong antigens, eliciting a stronger immune response to the poor antigen. This enhances the effectiveness and stability of the vaccine. Poor antigens are usually polysaccharides that are attached to strong protein antigens.

Non-internalizing ADCs have the ability to induce a potent anticancer activity in vivo when used with a suitable payload and may target a broad variety of different malignancies. At present, they mainly rely on labile linkers for drug release in close proximity to the target because the intact ADC cannot passively diffuse into cells. Sufficient experimental data prove the fact that collagen IV, tenascin-C, fibrin, the alternatively spliced extra domains A and B (EDA and EDB) of fibronectin and galectin-3-binding protein (Gal-3BP) are appealing targets for non-internalizing ADC development. Scientific findings offer a preclinical proof-of-concept for curative ADC targeting the tumor microenvironment that does not rely upon antigen internalization.

Branched linkers (Hydra Linkers) are featured by their multiple payload loading capacity. They are bi-functional linkers that contain a main stem with a functional group at one terminus and a “branching point” at the other end. 

3D cell culture is a range of techniques that grow cells into 3D structures. Driven by the desire of biochemical and biomedical scientists for experimental systems that better represent the in vivo environments, new materials and methods for 3D cell culture has been developed. Application of 3D cell culture has resulted in better data and innovative knowledge of tissue and cancer behavior.

PtLnX is a technical platform developed by Creative Biolabs and one of our collaberators that uses bis(ethylenediamine) platinum chloride [Pt(en)Cl2] as a linker core for ADC development.