Human serum cell culture is a technique for growing human cells outside the body in a controlled laboratory environment. This process uses human serum as a fundamental component of the cell culture medium. It supports scientific research and medical advancements by providing a more physiologically relevant system for studying human cells.
Understanding Human Serum
Human serum is the liquid portion of human blood that remains after blood clotting and the removal of cellular components like red blood cells, white blood cells, and platelets. It is distinct from whole blood, which contains all cellular elements, and plasma, which contains clotting factors like fibrinogen. Serum is obtained by allowing whole blood to clot naturally, then centrifuging the sample to separate the serum from the clot.
The composition of human serum is complex, containing growth factors, hormones, nutrients like sugars, salts, and lipids, and adhesion factors that help cells attach to surfaces in culture. It also contains antibodies, antigens, and electrolytes. Type AB human serum is preferred for cell culture because it lacks anti-A or anti-B antibodies, which could trigger an unwanted immune response in other cell types.
Role in Cell Growth and Health
Human serum provides a physiologically appropriate environment for the proliferation and differentiation of human cells in vitro. Its rich blend of growth factors, such as platelet-derived growth factor (PDGF), transforming growth factor-beta (TGF-β), and epidermal growth factor (EGF), stimulates cell division and regulates cell cycles. These components also contribute to cell attachment to culture surfaces, necessary for many cell types to thrive. The serum supplies essential nutrients and acts as a buffer against changes in pH, proteolytic activity, or the presence of heavy metals or endotoxins, maintaining cell viability.
Using human serum offers advantages over animal-derived sera, such as fetal bovine serum (FBS), especially when culturing human cells. Human serum more closely mimics the physiological conditions of the human body, which can lead to more accurate and relevant experimental results. Animal-derived components in FBS can provoke an immune response in human cells, altering experimental outcomes or causing immunogenicity issues in therapeutic applications. For instance, human mesenchymal stem cells (MSCs) have shown more rapid proliferation in human serum compared to FBS, while maintaining their differentiation capacity.
Key Applications
Human serum cell culture finds applications across scientific and medical fields. In drug discovery and testing, it enables researchers to evaluate the efficacy and toxicity of new pharmaceutical compounds in a physiologically relevant human system. This is particularly useful for personalized medicine approaches, where patient-specific cells can be cultured to predict individual responses to treatments. For example, human serum has been shown to influence cancer cell behavior, enhancing cell invasion and spheroid formation in certain cancer types compared to FBS.
The technique is also applied in regenerative medicine, where cells are grown outside the body to repair or replace damaged tissues and organs. Human serum supports the growth and differentiation of primary cells, such as bone marrow mesenchymal stem cells, human periosteum-derived cells, and human adipose-derived stem cells, which are candidates for tissue engineering. Human cell lines cultured with human serum can be used in vaccine production to propagate viruses for vaccine development. Human serum cell culture is also used for disease modeling, allowing scientists to study the mechanisms of various diseases, including cancer and autoimmune disorders, in a controlled environment that closely resembles the human body.
Considerations for Use
Despite its benefits, using human serum in cell culture involves several practical considerations and challenges. Donor variability is a factor, as the exact composition of serum can differ between individual donors, leading to inconsistencies between batches. This variability can influence cell growth and experimental reproducibility. To mitigate this, some laboratories pool serum from multiple donors or use single-gender pools to reduce variation.
Using human serum in cell culture involves several practical considerations and challenges:
- Ethical sourcing and consent are important. Suppliers obtain serum from healthy donors who provide informed consent, often through FDA-licensed collection facilities.
- Strict screening for pathogens, including viruses like HBV, HCV, HIV, HTLV, WNV, and Trypanosoma cruzi, ensures safety.
- Standardized collection and processing methods, including serial filtration, maintain quality and minimize contamination risks.
- The cost of human serum is higher than animal-derived alternatives, which can influence its widespread adoption.