Multiplexed Immunoassay Development for Antibodies Against Shigella

Bacillary dysentery is a major cause of death in developing countries, killing more than 100,000 people per year. The illness, which is characterized by severe diarrhea and fever, results when mucous-producing membranes in the colon and rectum become infected with Shigella spp. bacteria.

Luminex Assays

The body attempts to fight the Shigella infection through an immune response that involves producing antibodies against the bacteria. The detection of these antibodies is important for epidemiological studies of the spread of Shigella bacteria, and for research studies of immunity to the disease as a result of vaccination.

Until recently, the method most commonly used to detect the antibodies that are produced as part of the immune response to Shigella infection involved the analysis of samples of serum or colorectal mucous using the ELISA (enzyme-linked immunosorbent assay) technique. However, it is not always possible to acquire large enough samples from small animals and children to allow this method to be carried out for all relevant antibodies.

A recent study published by researchers at the Walter Reed Army Institute of Research used multiplexed Luminex® xMAP® Technology to detect and measure antibodies produced by the immune response to Shigella infection. This method not only required a smaller volume of sample than that required for serological analysis using ELISA, but was also faster and less labor intensive.

The main advantage of the Luminex multiplex platform is that it allows multiple assays for the detection of multiple antigens to be carried out simultaneously using a 96-well format. In this study of the immune response to Shigella, antibodies corresponding to six important Shigella antigens were measured using a single multiplex assay, which requires a much smaller sample volume than carrying out six separate single assays. Although the multiplex assay takes a similar length of time as an ELISA, it has the advantage of producing six times as much valuable data.

The following are all advantages of using Luminex multiplex immunoassay technology compared to an ELISA:

  • Uses smaller sample volumes
  • Each assay produces a larger range of results
  • Lower costs
  • Equally accurate results

The multiplexed immunoassay technique developed in the study could be highly useful in studies of the epidemiology of bacillary dysentery, as well as in studies involving vaccines against the disease.

To find out how you can develop your own multiplex assays, click here.