The subunit vaccine does not contain any intact bacteria or viruses at all. Instead, these vaccines usually contain one or more specific antigens from the surface of the pathogen. The advantage of subunit vaccines over whole-pathogen vaccines is that the immune response can be focused on recognizing a few antigen targets. Subunit vaccines do not always produce a strong or long-lasting immune response like live attenuated vaccines. They usually require repeated administration at the beginning and booster doses in subsequent years. Adjuvants are usually added to subunit vaccines. These substances help strengthen and prolong the immune response to vaccines. Alfa Chemistry provides customers with complete solutions to support their vaccine development process.
Recombinant Vaccine
Recombinant vaccines are vaccines produced through recombinant DNA technology. This involves inserting DNA encoding antigens (such as bacterial surface proteins) into bacterial or mammalian cells to stimulate an immune response, expressing the antigens in these cells, and then purifying them. Recombinant vaccines use bacteria or yeast cells to make vaccines. For example, in order to make a hepatitis B vaccine, part of the DNA of the hepatitis B virus is inserted into the DNA of yeast cells. These yeast cells can then produce a surface protein from the hepatitis B virus, purify it and use it as the active ingredient in the vaccine.
The virus is designed to look like a wild virus strain on the human immune system, but has no adverse effects. It is promising as a platform vaccine. The manufacturing process shares similar technologies with gene therapy and monoclonal antibody production, depending on the production cell line.
Upstream
Maintaining a single sterile environment is essential to a successful vaccine production process. This can be supported by the use of single-use technologies with integrated filtration and single-use bioreactors.
- Disposable bioreactor supporting suspension and adherent cell culture
- Sterilization grade gas filtration
- Sterilized liquid filtration for media filtration and aseptic addition
Harvest and Clarification
Maintaining high virus yields while isolating the virus from the host cell requires careful optimization. The disposable depth filtration platform supports simple clarification of cell cultures after centrifugation and low turbidity. Used in conjunction with centrifugation or alone, whole cells and cell debris can be easily removed using a disposable deep filtration system optimized for throughput and yield.
Media Preparation
Buffer and media preparation solutions to support upstream processing include mixed applications, storage, and transportation. Other operations (such as sterile filtration) can be integrated with mixing technology to create powerful automation solutions.
Purification
You can choose to use ultrafiltration cartridges for concentration and diafiltration based on size separation of pollutants.
Anion exchange membrane chromatography simplifies the removal of endotoxins and the removal of change-based contaminants such as host cell DNA, proteins, and endotoxins. It can also be used for combined elution operations to purify and concentrate viruses without high shear ultrafiltration.
For processes including mammalian cell culture, virus safety is an important consideration and can be managed through orthogonal control (such as inactivation and virus filtration).
Toxoid Vaccine
Some bacteria release toxins (toxic proteins) when they attack the body. What we want to resist is the toxins rather than the bacteria themselves. The immune system recognizes these toxins in the same way that it recognizes other antigens on the surface of bacteria and is able to produce an immune response to them. Some vaccines are made with inactivated versions of these toxins. They are called "toxoids" because they look like toxins but are not poisonous. They trigger a strong immune response, such as bacterial toxoid protein vaccines, which use inactivated bacterial toxins (toxoids) as antigens to prevent certain bacterial threats.
Upstream
Maintaining a single sterile environment is essential to a successful vaccine production process. This can be supported through the use of disposable technology and maintained through filtration.
- Disposable bioreactor
- Sterilization grade gas filtration
- Sterilized liquid filtration for media filtration and aseptic addition
Harvest and Clarification
Used in conjunction with centrifugation or alone, a disposable depth filtration system optimized for throughput and yield can easily remove entire cells and cell debris (such as K100P grade).
Media Preparation
Use our sterile filtration products to process mixed solutions for buffer and medium preparation to support upstream processing and formulation.
Purification
You can use our concentration and diafiltration products (such as ultrafiltration cartridges) to achieve size-based separation of contaminants. Anion exchange membrane chromatography can be used for endotoxin control and removal of contaminants through charge-based interactions.
Fluid Handling
Aseptic connectors and aseptic isolators control the risks associated with connecting and disconnecting fluid paths to protect operators, quality, and simplify handling when using disposable manufacturing techniques. This type of solution is very suitable for sterile preparations of multivalent vaccines, where sterile filtration may not be possible after adding some adjuvants.