Title: 5 Ways to Make ELISA a More Approachable Topic
Introduction: ELISA (Enzyme-Linked ImmunoSorbent Assays)
As science advances, it tries to ease the cumbersome and time-consuming methodologies of different techniques used for human welfare. ELISA is one of them. Before Eva Engvall and Peter Perlman invented this revolutionizing ‘antigen-antibody reaction-based test’ in 1971, the world was dependent upon RIA (RadioImmunoAssay). Now as we said science advances and improvises the techniques, and RIA’s intrinsic radiation hazards were finally overcome by ELISA.
The widespread applications that ELISA found were astonishing. It became the center of attention finding utilization across diverse domains like medicine, immunology research, FMCG industry, virology, and many more. From discerning cancer biomarkers to the identification of food allergens and from the detection of illicit drugs in serum samples to confirmation of pregnancy, ELISA became the favorite tool across the fields.
Now, teaching this wondrous subject to students at high school and university/college levels becomes difficult for educators due to many reasons. But since this topic finds such great usage in the Biological Sciences, we’ll take a leap and try to make a roadmap that educators and teachers can utilize for a lucid delivery of concepts related to ELISA in their next class.
This article can provide real help as it highlights the major blocks encountered by students and lists practical solutions to resolve them. By the end, we’ll share why a virtual lab simulation will prove useful not only for your students but also for you as an educator to deliver concepts more efficiently.
3 reasons why ELISA can be tricky to teach or learn
There are 3 reasons why students dread and confuse the topic of the ELISA technique. Acknowledging these blocks is the first step toward making the topic more approachable.
1. Finding it hard to follow the steps and their significance
Since ELISA has a list of steps starting from ‘well coating’ to ‘antibody treatments (primary and secondary)’ followed by ‘chromogenic reaction for detection using substrate’, students find themselves muddled amidst all of this. Further not knowing the roles of each of the steps and the chemicals involved worsens the situation for them. With the dearth of knowledge about ‘antigen-antibody reaction’, it can be pretty hard for students to grasp the basic principle of ELISA.
2. Lack of lab handling and visualization
Since the ELISA kits can pierce a hole in the pockets, it’s not possible for educators and teachers to give a chance to all the students to conduct their own ELISA tests in the practical labs. This deprives the students of practical lab handling. Then learning ELISA becomes a theoretically boring activity. Furthermore, students also complain about the lack of interactive ELISA videos on the internet. This unavailability ensures that ELISA either remains a dreadful subject or an ignored one for students.
3. Sounds like a complex and high-end biological tool
At its first introduction, ELISA is questioned by students due to its association with high-end science and technology. Plus its utilization majorly in the medicine and R&Ds of big pharmas portray its image as a very complex technique. Students are bound to get fearful of something that big. The long terminologies and the sophisticated names of the wash buffers, enzymes, substrates, etc further amplify the fear in students.
5 ways to make ELISA a more approachable topic to understand
In order to address the blocks encountered while teaching the ELISA technique, educators can engage the under-listed solutions in their classes. These can clarify many instrumental aspects of ELISA. Not only can they make teaching easier for educators like you but will also make lessons clearer and easier to assimilate for your students.
1. Demystify the complexities of ELISA
Tagging ELISA as a very complex Science technique begins as soon as the students are first introduced to this term. It becomes the primary duty of educators to break down this shell and make them look across the hall. Now, you can do this by explaining the different steps in an easier way. We have listed some of them for you to begin with.
1. There are only 3 main principles in the basic ELISA: Since ELISA is perceived to be a multi-step complex process, educators can explain that ELISA has only 3 basic principles involved. They are:
Antigen coating of the well (for immobilizing antigens)
Antibody treatment (for the formation of Ag-Ab complex; antigen-antibody)
Introduction of a substrate (for detection of Ag-Ab complex)
2. Explain why antigen coating is done: For the detection of proteins, peptides, hormones, and antibodies, the most proficient way is to exploit the “specificity of antigen-antibody reaction”. In order to detect the same from blood, serum, urine, and bodily secretion samples, the specific antigen for the molecule in question (peptide/protein/hormone/antibody) is first coated on the wells. This ensures that only our specific molecule is detected in the subsequent steps of ELISA.
By highlighting the importance of a basic immunology concept here, educators can demystify the air around ELISA.
You can further develop concepts around each of the steps and simplify the technique for your students.
Figure: This snippet from the ELISA (Enzyme-Linked ImmunoSorbent Assays) simulation by Labster’s virtual laboratory helps your students understand the basic immunology concept of specificity between antigen and antibody. It also shows how the secondary antibody (red Y-shaped structure) binds to the primary antibody (green Y-shaped structure). The enzyme (blue structure) is attached to the secondary antibody. The simulation is available for Professional and University / College classes.
2. Explain the roles of chemicals involved
Since there are multiple repetitive steps in the ELISA protocol, explaining the roles of major chemicals used in the technique can simplify it for the students to understand. The major chemical entities used in this technique are:
1. PBST: PBST is a combination of Phosphate buffered saline and Tween® 20 detergent. After the antigen coating of the polystyrene wells of the ELISA microplate, one wash step using PBST is involved. In a similar way, PBST is used after every consecutive incubation and blocking step in ELISA. (Role: PBST is a wash buffer that optimally stabilizes the pH of the wells. It also removes the excess salts and detergents from the wells. The major plus point of PBST is that it doesn’t disrupt the binding reaction between antigen and the ‘molecule in question’.)
2. BSA: BSA is Bovine Serum Albumin. It is used immediately after the antigen coating step. (Role: BSA is used to prevent any non-specific binding in the ELISA microplate wells. It blocks any leftover spaces after the antigen coating step, thereby called a blocking agent.)
Similarly explaining the roles of different chemicals can help your students in understanding the rationale of using them. Such an understanding driven class can never be boring.
Figure: This snippet from the ELISA (Enzyme-Linked ImmunoSorbent Assays) simulation by Labsterdemonstrates the lab setup required for performing ELISA. It is available for Professional and University / College classes.
3. Try to demonstrate at least some of the ‘chromogenic’ enzymatic reactions that lie at the heart of the detection step in ELISA
Demonstrating the entire protocol of ELISA in class at the high school or college level might be hard due to the unavailability of kits or lack of funds. This is understandable. But educators can at least try to source some of the enzymes that are linked to the secondary antibodies and their respective substrates.
Since the detection step of ELISA is based on the enzymatic reaction that is essentially chromogenic, this effort of sourcing the enzyme and substrate can give your students a sneak peek at how ELISA works.
This will also clarify the role of the enzyme that’s linked to the secondary antibody. Plus it will also illuminate the necessary interaction of the primary antibody (the molecule in question) and secondary antibody (carrying enzyme).
Some of the enzymes that you can source are horse radish peroxidase and alkaline phosphatase.
4. Relate it to real-world applications
ELISA is one of the favorite techniques of biologists across different sub-domains. It finds varied utilities due to its high specificity and sensitivity. Listing a few of its major real-world applications can make the technique seem practical and worthy to learn. We have listed some of the examples where ELISA finds its maximum utilization.
1. Clinical use-‘Detection of cancer’: ELISA is widely being used for the purpose of early detection of cancers and their aggressiveness. It serves as an effective tool for measuring the different cancer biomarkers. These biomarkers are usually those biomolecules that the body starts producing in response to cancerous growth and development. Some of the clinically identified and targeted biomarkers are anaplastic lymphoma receptor tyrosine kinase (ALK), alpha-fetoprotein (AFP), and carcinoembryonic antigen (CEA). These are of both clinical practice and research-oriented usages.
2. Public use-‘Pregnancy Tests’: ELISA is also widely exploited to confirm pregnancy in pregnancy kits. These ELISA tests work by detection of the pregnancy hormone, hCG (human chorionic gonadotropin). As soon as the developing embryo attaches itself to the mother’s uterus which generally times between 6th to 12th day after conception, the placenta of the mother starts secreting hCG. The ELISA kit has anti-hCG mobile antibodies. And hCG is eliminated in the urine of the female body. When the woman takes the test, the presence of hCG (positive pregnancy) is detected by a successful antigen-antibody reaction leading to the formation of hCG-anti hCG complex. And since the anti-hCG (antibody) carries an enzyme that mediates a chromogenic reaction, we see a colored indicator (usually a pink line formation).
Since such examples are easy to associate with, teachers should employ them to deliver effective lessons about ELISA. As educators, you can research and find more such examples to make your class more interactive and engaging.
Figure: This snippet from the ELISA (Enzyme-Linked ImmunoSorbent Assays) simulation by Labster’s virtual laboratory helps your students engage using gamification elements. It is available for Professional and University / College classes.
5. Use virtual lab simulations
Since ELISA can be too theoretical in absence of lab handling sessions, educators are advised to search for visually interactive videos. YouTube doesn’t always provide such an option for all the topics. In order to overcome this visualization constraint in the learning process of the students, virtual laboratory simulations from Labster provide teachers with an option to use ELISA (Enzyme-Linked ImmunoSorbent Assays) simulation. This can help in making more insightful points as students are rendered with better visual options. Your students don’t have to struggle to imagine different steps of ELISA themselves as our interactive simulation along with gamification elements comes to the rescue. By using this way of active and immersive teaching, our virtual learning platform takes an advent in the field of Science to make the upcoming scientists thorough with the “basics of their respective subjects”.
Figure: This snippet is from the ELISA (Enzyme-Linked ImmunoSorbent Assays) simulation by Labster. It engages your student in the data analysis of ELISA. It is available for Professional and University / College classes.