ANTITECK - Medical Device Assembly Automation Solution & Lab Equipment
biology-lab-equipment

What Is the function of rabbit antibodies in a basic immunochromatography assay?

Posted on September 7, 2024 by AntiTeckLateral Flow

Rabbit antibodies are used in most diagnostic assays, especially in immunochromatography, which is the most used technique for the detection of analytes. Immunochromatography assays are based on the reaction of antigens with antibodies and rabbit antibodies are used as such because of high specificity, sensitivity, and ability to recognize different antigens. 

The rabbit antibodies used in immunochromatography assays will therefore be discussed in this article, why they are chosen, and how they enhance the operations of the assay. 

Introduction to Immunochromatography Assays

Immunochromatography also referred to as Lateral Flow Immunoassay (LFIA) is an analytical technique that can be used to detect target molecules in different body fluids such as blood, urine, or saliva. It is typical in point-of-care testing such as pregnancy testing kits and the most recent rapid COVID-19 tests. 

In an immunochromatography assay, the antibodies are used as the reagent to identify the presence of the specific antigen in the sample. Antibodies are materials that bind themselves to antigens which are materials that are not part of the body for instance bacteria or poison. Since antibodies possess high specificity and affinity to the target antigen, the immunochromatography assays can readily detect the presence of the target substance in a sample even in low concentrations. 

Rabbit antibodies are preferred in these assays because of the following advantages which are explained in detail below.  

The Function of Rabbit Antibodies in Immunochromatography 

Target Recognition 

As mentioned before, the primary function of rabbit antibodies in immunochromatography assays is the recognition of the target. The antibodies that are produced from rabbits are very selective and these are very selective in reacting with the particular antigens. This ability is particularly useful in the identification of analytes in a sample that may contain a lot of interfering substances.

Signal Generation 

Rabbit antibodies are usually conjugated with detection reagents such as colloidal gold, colored latex beads, or fluorochromes. In an immunochromatography assay if the antibodies of rabbit origin attach to the target antigen then the conjugated molecules of detection produce color on the test strip. This signal can be in the form of a coloured line as seen in colloidal gold or fluorescence as seen in fluorescent markers thus making it easy to determine the result of the test. 

Amplification of Response 

Rabbit antibodies are of high affinity and avidity which implies that the antibodies have a high inclination towards the target antigen. Because of the strong binding affinity, it increases the signal in the assay and therefore increases the sensitivity of the assay. Rabbit antibodies are very sensitive and they can grab the target antigen whereby the antigen could be present in a low concentration in the sample so that there will be a visible result on the test strip. This amplification of response is especially useful in diagnostic tests where the amount of target molecule is low. 

Development of Test line and Control line 

The immunochromatography assay is usually carried out using a test strip which possesses a test line and a control line. These rabbit antibodies used in the assay are the ones that develop both lines. The test line has immobilized rabbit antibodies which have the capacity of binding with the antigen. 

The control line is characterized by enzymes that can react with any non-target rabbit-conjugated antibodies that are not bound to the target antigen. A control line means that the test has worked in the right manner and that the antibodies have passed through the strip as they should even if the target antigen is not present.

Why Are Rabbit Antibodies Used in Immunochromatography? 

The sensitivity of the screening tool should be higher and the specificity of the tool should also be higher. Rabbit antibodies are rather sensitive and selective thus suitable for immunochromatography assays. It can be designed to measure small molecules such as haptens, and large molecules including viruses and hormones, and is capable of being made specific to a particular antigen with minimal interference from other antigens. This ensures that the assay produces the correct reading that is required for the particular sample and not other constituents that may be in the sample. 

Broad Immune Response 

Rabbits give very good immunogenic reactions to the antigens and generate antibodies that can well identify the epitopes that other antibodies of other animals cannot identify. The non-specificity of rabbit antibodies makes it ideal in the diagnostic processes especially when sensitivity is of importance.  

Stability and Durability 

Rabbit antibodies are known to be stable and even if the solution containing these antibodies is washed several times the antibodies are still active which is very essential for LFA. These antibodies can be stored for long periods without the loss of their activity and hence they can be produced in large quantities for use in different testing situations. Also, they do not affect external conditions like temperature variation humidity, and such. 

Applications of Rabbit Antibodies in Immunochromatography

Rabbit antibodies are used in a wide range of immunochromatography applications across various industries, Rabbit antibodies have been used in the immunochromatography processes and have been reported in a wide of fields including: 

Medical Diagnostics 

Rabbit antibodies are employed widely in clinical diagnostics for the identification of pathogens, hormones, and biomarkers. For instance, a home pregnancy test employs the use of rabbit antibodies to identify the presence of hCG in the urine of a woman. Likewise, rabbit antibodies are employed in the rapid diagnostic tests of other infectious diseases such as malaria, HIV, and COVID-19

Food Safety Testing 

Rabbit antibodies are used in the identification of the spoilage agents in the food samples such as bacteria, toxins, and allergens. For instance, immunochromatography assays can be applied for the screening of E. coli or salmonella in meals. Rabbit antibodies are ideal for this application because of the very high selectivity and sensitivity towards any residual impurities. 

Conclusion 

Rabbit antibodies are used in immunochromatography assays because of their ability to selectively bind with different types of antigens with great sensitivity. These properties help to make the tests more effective since they are stable and have high binding affinity. While rabbit antibodies have numerous benefits, some of the issues that must be taken into account include the price and batch-to-batch difference. Thus, rabbit antibodies will stay a reliable and valuable tool for diagnostics in the process of the point-of-care testing field development.

FAQ’s

Q1: Why are rabbit antibodies preferred over other types of antibodies in immunochromatography?

Rabbit antibodies are used in the assays since they are sensitive and specific as compared to other antibodies. They can recognize a large number of antigens; therefore, they are used in diagnostics in medicine, food, and ecology. 

Q2. Do rabbit antibodies have the ability to detect more than one product in one test? 

 Indeed, rabbit antibodies can be used in multiplex assays for the identification of several analytes on the same test strip provided that the antibodies can bind to different sites of the test. 

Q3. In other words, what can affect the efficiency of the use of rabbit antibodies in immunochromatography? 

 Some of the factors that may result in variability include the quality of the antibodies used in the assay, the concentration of the target antigen, and the storage condition. To eliminate such problems, the management of strips and the design of the strips also help to keep the accuracy intact.

ANTITECK provide uncut sheet rapid test for immunochromatographic test manufacturing, contact us for more information via [email protected]

Maybe you also interested: how to set up a manufacturing unit for drug test kit production?
How To Setup Lateral Flow Assay Manufacturing Factory?

Recent Posts

We use cookies in order to give you the best possible experience on our website. By continuing to use this site, you agree to our use of cookies.
Accept
Privacy Policy