We use cookies to make your experience better. To comply with the new e-Privacy directive, we need to ask for your consent to set the cookies. Learn more.
ELISA Detection of Serum Proteins
ELISA Detection of Serum Proteins
Serum proteins perform many essential functions. However, changes in their normal concentrations or the presence of unexpected proteins in serum may be indicative of disease. ELISA is widely used for measuring serum proteins due to its sensitivity, flexibility, and capacity to provide quantitative results, as well as for its compatibility with automation. We offer an extensive selection of serum protein antibodies, antigens, and ready-to-use ELISA kits, all of which we develop and manufacture in-house using internal gold standard controls for validation.
What is serum?
Blood has four main components – red blood cells, white blood cells, platelets, and plasma – of which plasma is the liquid in which all the other components reside. Plasma is approximately 90% water, with the remaining 10% comprising ions, nutrients, dissolved gases, waste, and many different types of proteins. When plasma is stripped of clotting factor proteins, it is known as serum.
What are some common serum proteins?
Albumin is the most abundant serum protein, accounting for around 55% of the total protein in blood. It functions to maintain the osmotic pressure between blood vessels and tissues, as well as serves as a carrier for substances such as hormones, calcium, bilirubin, anticoagulants (e.g., antithrombin and heparin cofactor), and various drugs. Globulins are another major class of serum proteins, and are categorized into alpha 1, alpha 2, beta, and gamma subgroups. While alpha and beta globulins act as both enzymes and carrier proteins, gamma globulins are mainly immunoglobulins (antibodies) with essential roles in the immune system. Many other proteins can be found in serum, where they may be measured as biomarkers of disease.
Which serum proteins are used as biomarkers?
The number of serum proteins used as biomarkers continues to grow as researchers learn more about the mechanisms of disease. The following are some well-known examples:
-
Albumin
-
Alpha-1-Antichymotrypsin
-
C3
-
Hemoglobin
Since albumin is produced in the liver, serum albumin is often used as a biomarker for liver disease (e.g., cirrhosis, fatty liver disease, liver cancer, or hepatitis A, B or C). Low serum albumin levels may also be indicative of conditions including kidney disease, thyroid disease, cardiovascular disease, and inflammation.
Alpha-1-antichymotrypsin is an alpha 1 globulin that protects the lower respiratory tract by inhibiting serine proteases such as neutrophil cathepsin G and mast cell chymases. Individuals with an alpha-1-antichymotrypsin deficiency are considered more likely to develop chronic obstructive pulmonary disease (COPD) and may also be at increased risk of Parkinson’s and Alzheimer’s disease.
Alpha-1-antichymotrypsin is an alpha 1 globulin that protects the lower respiratory tract by inhibiting serine proteases such as neutrophil cathepsin G and mast cell chymases. Individuals with an alpha-1-antichymotrypsin deficiency are considered more likely to develop chronic obstructive pulmonary disease (COPD) and may also be at increased risk of Parkinson’s and Alzheimer’s disease.
Hemoglobin is found in red blood cells, where it binds oxygen for transport to tissues and organs. If hemoglobin is present in serum, it may suggest hemolytic anemia, either due to an intrinsic condition such as sickle cell anemia or as a result of an infection, autoimmune disorder, or cancer. Serum hemoglobin can also indicate an adverse reaction to a blood transfusion.
What are the main challenges for serum protein detection?
Because serum contains many different proteins, highly specific antibodies are essential to accurately detect targets of interest. Sandwich ELISA is generally preferred for serum protein detection since, by using two anti-analyte antibodies that each target a different epitope, it offers improved specificity over direct assay formats. For detecting serum proteins that are present at low concentrations – often into the picomolar range – antibodies must also be highly sensitive. A further challenge for serum protein detection stems from the short half-lives of some target analytes, which makes careful sample handling essential.
Supporting serum protein detection
We offer a broad range of products for serum protein detection, including sandwich ELISA kits for human albumin, alpha 1-antichymotrypsin, C3, and hemoglobin which regularly feature among our best-sellers. By choosing to partner with ICL, you are assured of consistent batch-to-batch performance, reliable long-term supply, and expert technical support – attributes that have led to product citations in multiple journals.
Typical standard curve data for the Human Albumin ELISA Kit (catalog # E-80AL)