Lab Report: 10 ELISA Purpose: This test is often used to see if you have been exposed to viruses or other infectious substances. It is frequently used to screen for present or past infections. Introduction: ELISA stands for enzyme-linked immunoassay. It is a commonly used laboratory test to detect antibodies in the blood. An ELISA or enzyme-linked immunosorbent assay is a method used in the laboratory to aid in the diagnosis of a wide range of diseases.
This test is performed on blood or urine and is used for measuring the amount of a particular protein or substance in these bodily fluids, such as infectious agents, allergens, hormones or drugs. This test relies on the interaction between components of the immune system called antigens and antibodies. Antibodies are proteins produced by the body to identify and neutralize any foreign substances that may be encountered, such as viruses and bacteria.
The substances to which antibodies are produced are known as the antigens as they stimulate an immune response. If antibodies are being detected for example to HIV, then a portion of the HIV virus is attached to a solid surface such as a tube or plate. This will act as the antigen. Your serum will then be added to the tube and if it contains antibodies to the antigen then it will bind to it. Another antibody which recognizes the HIV antibodies is then added and binds to any bound antibody.
This second antibody is linked with a chemical known as an enzyme (an enzyme speeds up a chemical reaction) and in the final step a substance (peroxidase) which reacts with the enzyme on the antibody is added to produce a colored product. If the test is positive then a color reaction will occur. If you don’t have antibodies to that certain antigen then no reaction will occur and no color change will be seen. Materials: PBS, HIV antigen, Peridase, donor 1, donor 2, well, tips, pipette, 2C AB Method: First you label well 1-4.
Then you add 100ul of A to each well letting it sit for 5 mins at room temperature. Next you remove the liquid from each well. Then you add 100ul of PBS to each well, and then remove it. After that, to each well using different tip each time add 100ul PBS to number 1, add 100ul B to number 2, add 100ul C to number 3 and add 100ml D to number 4. Incubate at 37C (Body temp) for 15 mins. After that, remove liquid using different tips. Next add 100ul PBS, and then remove using different tips. Add 100ul 2C AB to each well and incubate at 37C for 15 min. emove the liquid using different tips, add PBS then remove the PBS. Add 100ul of substrate to each well and incubate at 37C for 5 mins. A= HIV Antigens B= Positive control C= Donor 1 serum D= Donor 2 serum PBS= Phosphate Buffered Saline Results: A| B| C| D| 1| 2| 3| 4| -| +| -| +| Conclusion: For the first row, the results can back negative because that was the control. The second column was positive meaning for this control this is what a positive would look like. Now from the third column this donor serum is just negative for that antibody and the fourth row would be a positive for HIV antibodies.
This test is medically important because it’s used for measuring certain hormone levels such as HCG in the pregnancy test, thyroid hormones, detecting dust and food allergies, detection of illicit drugs such as cocaine and methamphetamines. Also to measuring antibodies which are produced in auto-immune conditions such as Lupus and rheumatoid arthritis. Some kits are also available for the general public to use for example; the home pregnancy test is based on the ELISA principle and detects the presence of a hormone known as human chorionic gonadotrophin (hCG) which is excreted in the urine of a pregnant woman.