What is Serum?
Serum is the clear, pale-yellow liquid that remains after blood has clotted. It is essentially blood plasma without the
clotting factors, such as fibrinogen. Serum is used in various diagnostic tests and research settings to study the biochemical and physiological state of the organism.
How is Serum Obtained?
Serum is obtained by allowing the blood to clot and then centrifuging to separate the solid components from the liquid. The blood sample is collected in a tube without anticoagulants, allowing the clotting process to occur naturally. After clotting, the sample is centrifuged, and the serum is carefully extracted from the top layer.
What is the Role of Serum in Histology?
In histology, serum is often used in immunohistochemistry (IHC) procedures to block non-specific binding sites. This helps in reducing background staining and enhances the
specificity of the antibody-antigen interaction. Normal serum from the same species as the secondary antibody is commonly used in the blocking step.
How is Normal Serum Used in Immunohistochemistry?
During IHC, normal serum is used to pre-incubate tissue sections before the primary antibody is applied. This step helps to block non-specific sites and prevent the secondary antibody from binding to non-target tissues. For example, if a secondary antibody is raised in goat, normal goat serum is used for blocking.
What are the Benefits of Using Normal Serum?
Using normal serum in histological techniques offers multiple benefits. It reduces non-specific background staining, thereby increasing the signal-to-noise ratio. This allows for clearer visualization of specific antigens. Additionally, it can improve the overall quality and reproducibility of the histological analysis.
What Factors Influence the Quality of Normal Serum?
The quality of normal serum can be influenced by several factors including the health status of the donor, the method of collection, and the storage conditions. It is essential to use fresh or properly stored serum to ensure optimal results in histological applications.
How Should Normal Serum Be Stored?
Normal serum should be stored at -20°C or lower to preserve its integrity. Once thawed, it should be used promptly and should not be refrozen to avoid degradation of its components. Proper storage is crucial to maintain the serum’s effectiveness in blocking and other applications.
Conclusion
Normal serum plays a vital role in histology, particularly in techniques like immunohistochemistry. Its ability to block non-specific binding sites enhances the specificity and clarity of histological analyses. Proper collection, storage, and usage of normal serum are pivotal for achieving reliable and reproducible results.
