Principles and application of a highly quantitative liquid phase immunoassay (luciferase immunoprecipitation system) for profiling humoral immune responses in patient sera samples

Background: Studying immunoglobulin responses by serological techniques is imperative for evaluating antibody titer values during the course of an infection, immune responses in autoimmune disease and vaccines. So the presence of a rapid, high-throughput, cost-effective and also safe method which can minimize both false positive-and false negative-cases is beneficial for early diagnosis and accurate treatment of patient. Accordingly, study ahead focused on introducing the principles and application of a novel solution phase immunoassay called luciferase immunoprecipitation system (LIPS). Search method: The study was conducted by searching the English and Persian databases including MEDLINE, Pubmed, Springer, Ovid, Google Scholar, Magiran, reference lists of relevant papers and reviews and grey literature databases. We used original and review articles that published up to February 2015.Among 42 related articles, 30 articles with full text access were reviewed. Findings: Luciferase immuoprecipitation system is a nonradioactive diagnostic approach applied for assessment humoral responses in which target antigen is fused to the enzyme reporter renilla luciferase (Ruc) for generating Ruc-antigen fusion protein which is performed by designing and cloning appropriate plasmid expression vector in format of pREN2 or pREN3S (mammalian Ruc expression vector), then the recombinant plasmids are transferred to Cos1 cells for exerting mammalian-specific posttranslational modifications. After lysing Cos1 cells, Ruc-antigen extracts are directly used in LIPS without purification. This process basically involves blending patient sera samples and tagged Ruc antigen together, then the admixture of Ruc-antigen-antibody complex is loaded to a microtiter filter plate containing protein A/G beads to trap antibodies. Eventually, after the filter plate is rinsed out from unbound Ruc-antigen with wash buffer, coelenterazine substrate is added to emit blue light of 480 nm reported as light units by a luminometer.Conclusion: The results suggest that LIPS has some merits such as, having high specificity and sensitivity with a liner dynamic range of detection, being safe and cost-effective, profiling antibodies without the need for advanced equipment, rapid and simple detection. Accordingly, LIPS is extremely informative tool compared with ELISA and RIA for monitoring antibody responses associated with autoimmunity, vaccines and variety of infectious agents.

کلیدواژه ها:

luciferase immunoprecipitation systems ، quick LIPS ، antibody profiling ، infectious disease ، autoimmune disease ، vaccine research